Added more stats

Added more dependency injection
Made README.md better

EonaCat.LogStack.Status/Services/SyslogService.cs

@@ -119,7 +119,9 @@ public class SyslogUdpService : BackgroundService
         try
         {
             if (IsJson(rawMessage))
+            {
                 return ParseJson(rawMessage, remoteIp);
+            }
 
             return ParseSyslogAdvanced(rawMessage, remoteIp);
         }

EonaCat.LogStack/AdvancedMetricsCollector.cs

@@ -0,0 +1,263 @@
+using EonaCat.LogStack.Analytics;
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+
+namespace EonaCat.LogStack;
+
+// This file is part of the EonaCat project(s) which is released under the Apache License.
+// See the LICENSE file or go to https://EonaCat.com/License for full license details.
+
+/// <summary>
+/// Advanced metrics collector that provides comprehensive analytics across loggers
+/// </summary>
+public sealed class AdvancedMetricsCollector
+{
+    private readonly List<EonaCatLogStack> _loggers = new();
+    private readonly object _lock = new();
+
+    /// <summary>
+    /// Registers a logger for metrics collection
+    /// </summary>
+    public void RegisterLogger(EonaCatLogStack logger)
+    {
+        if (logger != null)
+        {
+            lock (_lock)
+            {
+                if (!_loggers.Contains(logger))
+                {
+                    _loggers.Add(logger);
+                }
+            }
+        }
+    }
+
+    /// <summary>
+    /// Unregisters a logger
+    /// </summary>
+    public void UnregisterLogger(EonaCatLogStack logger)
+    {
+        if (logger != null)
+        {
+            lock (_lock)
+            {
+                _loggers.Remove(logger);
+            }
+        }
+    }
+
+    /// <summary>
+    /// Gets aggregated metrics across all registered loggers
+    /// </summary>
+    public AggregatedMetrics GetAggregatedMetrics()
+    {
+        lock (_lock)
+        {
+            var aggregated = new AggregatedMetrics
+            {
+                Timestamp = DateTime.UtcNow,
+                LoggerMetrics = new List<LoggerMetrics>()
+            };
+
+            foreach (var logger in _loggers)
+            {
+                try
+                {
+                    var metrics = logger.GetMetrics();
+                    aggregated.LoggerMetrics.Add(metrics);
+                }
+                catch { }
+            }
+
+            // Aggregate totals
+            aggregated.TotalLoggedAcrossAll = aggregated.LoggerMetrics.Sum(m => m.TotalLogged);
+            aggregated.TotalDroppedAcrossAll = aggregated.LoggerMetrics.Sum(m => m.TotalDropped);
+            aggregated.TotalExceptionsAcrossAll = aggregated.LoggerMetrics.Sum(m => m.TotalExceptions);
+            aggregated.TotalBytesAcrossAll = aggregated.LoggerMetrics.Sum(m => m.TotalBytes);
+            aggregated.ActiveLoggers = _loggers.Count;
+
+            return aggregated;
+        }
+    }
+
+    /// <summary>
+    /// Gets a performance comparison across loggers
+    /// </summary>
+    public PerformanceComparison GetPerformanceComparison()
+    {
+        var aggregated = GetAggregatedMetrics();
+
+        return new PerformanceComparison
+        {
+            Timestamp = aggregated.Timestamp,
+            TotalLoggers = aggregated.ActiveLoggers,
+            HighestThroughputLogger = aggregated.LoggerMetrics.OrderByDescending(m => m.WritesPerSecond).FirstOrDefault(),
+            LowestSuccessRateLogger = aggregated.LoggerMetrics.OrderBy(m => m.SuccessRate).FirstOrDefault(),
+            AverageBytesPerEvent = aggregated.LoggerMetrics.Count > 0 
+                ? aggregated.LoggerMetrics.Average(m => m.AverageBytesPerEvent)
+                : 0,
+            AverageWritesPerSecond = aggregated.LoggerMetrics.Count > 0
+                ? aggregated.LoggerMetrics.Average(m => m.WritesPerSecond)
+                : 0
+        };
+    }
+
+    /// <summary>
+    /// Gets a health report
+    /// </summary>
+    public HealthReport GetHealthReport()
+    {
+        var aggregated = GetAggregatedMetrics();
+
+        var report = new HealthReport
+        {
+            Timestamp = aggregated.Timestamp,
+            OverallStatus = "Healthy",
+            Warnings = new List<string>(),
+            Errors = new List<string>()
+        };
+
+        foreach (var logger in aggregated.LoggerMetrics)
+        {
+            if (logger.SuccessRate < 95)
+            {
+                report.Warnings.Add($"{logger.GetType().Name}: Low success rate ({logger.SuccessRate:F1}%)");
+            }
+
+            if (logger.TotalExceptions > logger.TotalLogged * 0.05) // More than 5% exceptions
+            {
+                report.Warnings.Add($"Logger: High exception rate ({logger.TotalExceptions} exceptions)");
+            }
+        }
+
+        if (report.Warnings.Count > 0)
+        {
+            report.OverallStatus = "Warning";
+        }
+
+        if (report.Errors.Count > 0)
+        {
+            report.OverallStatus = "Error";
+        }
+
+        return report;
+    }
+
+    /// <summary>
+    /// Resets all metrics
+    /// </summary>
+    public void Reset()
+    {
+        lock (_lock)
+        {
+            _loggers.Clear();
+        }
+    }
+}
+
+/// <summary>
+/// Aggregated metrics across multiple loggers
+/// </summary>
+public sealed class AggregatedMetrics
+{
+    public DateTime Timestamp { get; set; }
+    public List<LoggerMetrics> LoggerMetrics { get; set; } = new();
+    public long TotalLoggedAcrossAll { get; set; }
+    public long TotalDroppedAcrossAll { get; set; }
+    public long TotalExceptionsAcrossAll { get; set; }
+    public long TotalBytesAcrossAll { get; set; }
+    public int ActiveLoggers { get; set; }
+
+    public double OverallSuccessRate
+    {
+        get
+        {
+            var total = TotalLoggedAcrossAll + TotalDroppedAcrossAll;
+            return total > 0 ? (TotalLoggedAcrossAll * 100.0) / total : 100;
+        }
+    }
+
+    public override string ToString()
+    {
+        var sb = new StringBuilder();
+        sb.AppendLine("===== AGGREGATED METRICS =====");
+        sb.AppendLine($"Timestamp: {Timestamp:O}");
+        sb.AppendLine($"Active Loggers: {ActiveLoggers}");
+        sb.AppendLine($"Total Logged: {TotalLoggedAcrossAll:N0}");
+        sb.AppendLine($"Total Dropped: {TotalDroppedAcrossAll:N0}");
+        sb.AppendLine($"Overall Success Rate: {OverallSuccessRate:F2}%");
+        sb.AppendLine($"Total Exceptions: {TotalExceptionsAcrossAll:N0}");
+        sb.AppendLine($"Total Bytes: {TotalBytesAcrossAll:N0}");
+        sb.AppendLine("==============================");
+        return sb.ToString();
+    }
+}
+
+/// <summary>
+/// Performance comparison across loggers
+/// </summary>
+public sealed class PerformanceComparison
+{
+    public DateTime Timestamp { get; set; }
+    public int TotalLoggers { get; set; }
+    public LoggerMetrics HighestThroughputLogger { get; set; }
+    public LoggerMetrics LowestSuccessRateLogger { get; set; }
+    public double AverageBytesPerEvent { get; set; }
+    public double AverageWritesPerSecond { get; set; }
+
+    public override string ToString()
+    {
+        var sb = new StringBuilder();
+        sb.AppendLine("===== PERFORMANCE COMPARISON =====");
+        sb.AppendLine($"Timestamp: {Timestamp:O}");
+        sb.AppendLine($"Total Loggers: {TotalLoggers}");
+        sb.AppendLine($"Highest Throughput: {HighestThroughputLogger?.WritesPerSecond:F2} events/sec");
+        sb.AppendLine($"Lowest Success Rate: {LowestSuccessRateLogger?.SuccessRate:F2}%");
+        sb.AppendLine($"Average Bytes/Event: {AverageBytesPerEvent:F2}");
+        sb.AppendLine($"Average Writes/Second: {AverageWritesPerSecond:F2}");
+        sb.AppendLine("==================================");
+        return sb.ToString();
+    }
+}
+
+/// <summary>
+/// Health report for logging system
+/// </summary>
+public sealed class HealthReport
+{
+    public DateTime Timestamp { get; set; }
+    public string OverallStatus { get; set; } = "Unknown";
+    public List<string> Warnings { get; set; } = new();
+    public List<string> Errors { get; set; } = new();
+
+    public override string ToString()
+    {
+        var sb = new StringBuilder();
+        sb.AppendLine("===== HEALTH REPORT =====");
+        sb.AppendLine($"Timestamp: {Timestamp:O}");
+        sb.AppendLine($"Status: {OverallStatus}");
+
+        if (Warnings.Count > 0)
+        {
+            sb.AppendLine("\nWarnings:");
+            foreach (var warning in Warnings)
+            {
+                sb.AppendLine($"  - {warning}");
+            }
+        }
+
+        if (Errors.Count > 0)
+        {
+            sb.AppendLine("\nErrors:");
+            foreach (var error in Errors)
+            {
+                sb.AppendLine($"  - {error}");
+            }
+        }
+
+        sb.AppendLine("========================");
+        return sb.ToString();
+    }
+}

EonaCat.LogStack/EonaCat.LogStack.csproj

@@ -14,7 +14,7 @@ It features a rich fluent API for routing log events to dozens of destinations f
     <Copyright>EonaCat (Jeroen Saey)</Copyright>
     <PackageTags>EonaCat;Logger;EonaCatLogStack;Log;Writer;Flows;LogStack;Memory;Speed;Jeroen;Saey</PackageTags>
     <PackageIconUrl />
-    <FileVersion>0.0.8</FileVersion>
+    <FileVersion>0.0.9</FileVersion>
     <PackageReadmeFile>README.md</PackageReadmeFile>
     <GenerateDocumentationFile>True</GenerateDocumentationFile>
     <PackageLicenseFile>LICENSE</PackageLicenseFile>
@@ -25,7 +25,7 @@ It features a rich fluent API for routing log events to dozens of destinations f
   </PropertyGroup>
 
 	<PropertyGroup>
-		<EVRevisionFormat>0.0.8+{chash:10}.{c:ymd}</EVRevisionFormat>
+		<EVRevisionFormat>0.0.9+{chash:10}.{c:ymd}</EVRevisionFormat>
 		<EVDefault>true</EVDefault>
 		<EVInfo>true</EVInfo>
 		<EVTagMatch>v[0-9]*</EVTagMatch>
@@ -36,7 +36,7 @@ It features a rich fluent API for routing log events to dozens of destinations f
 	</PropertyGroup>
 
     <PropertyGroup>
-      <Version>0.0.8</Version>
+      <Version>0.0.9</Version>
       <PackageId>EonaCat.LogStack</PackageId>
       <Product>EonaCat.LogStack</Product>
       <RepositoryUrl>https://git.saey.me/EonaCat/EonaCat.LogStack</RepositoryUrl>
@@ -50,6 +50,12 @@ It features a rich fluent API for routing log events to dozens of destinations f
       </PropertyGroup>
     </Target>
 
+    <ItemGroup>
+      <Compile Remove="Examples\**" />
+      <EmbeddedResource Remove="Examples\**" />
+      <None Remove="Examples\**" />
+    </ItemGroup>
+
 	<ItemGroup>
     <None Remove="icon.png" />
     <None Include="..\LICENSE">
@@ -91,4 +97,7 @@ It features a rich fluent API for routing log events to dozens of destinations f
       <PackagePath>\</PackagePath>
     </None>
   </ItemGroup>
+  <ItemGroup>
+    <Folder Include="EonaCatLoggerCore\Examples\" />
+  </ItemGroup>
 </Project>

EonaCat.LogStack/EonaCatLogger.cs

@@ -1,12 +1,15 @@
-using EonaCat.LogStack.Boosters;
+using EonaCat.LogStack.Analytics;
+using EonaCat.LogStack.Boosters;
 using EonaCat.LogStack.Core;
 using EonaCat.LogStack.Flows;
 using System;
 using System.Collections.Concurrent;
 using System.Collections.Generic;
+using System.Diagnostics;
 using System.Linq;
 using System.Runtime.CompilerServices;
 using System.Threading;
+using System.Threading.Channels;
 using System.Threading.Tasks;
 
 // This file is part of the EonaCat project(s) which is released under the Apache License.
@@ -30,12 +33,35 @@ namespace EonaCat.LogStack
         private volatile bool _isDisposed;
         private long _totalLoggedCount;
         private long _totalDroppedCount;
+        private long _totalExceptionsCount;
+        private long _totalByteCount;
+        private readonly Stopwatch _startTime = Stopwatch.StartNew();
+
+        // Per-level counters
+        private long _traceCount;
+        private long _debugCount;
+        private long _informationCount;
+        private long _warningCount;
+        private long _errorCount;
+        private long _criticalCount;
+
+        // Metrics tracking
+        private readonly LoggingMetrics _metrics = new LoggingMetrics();
+        private readonly ConcurrentDictionary<string, PerFlowStatistics> _flowStats = new();
 
         private readonly List<ActionRef<LogEventBuilder>> _modifiers = new List<ActionRef<LogEventBuilder>>();
         public delegate void ActionRef<T>(ref T item);
 
         private readonly object _modifiersLock = new object();
 
+        // Channel-based async pipeline
+        private Channel<LogEvent>? _asyncChannel;
+        private Task? _asyncConsumer;
+        private CancellationTokenSource? _asyncCts;
+
+        // Dynamic level controller
+        private volatile DynamicLevelController? _dynamicLevel;
+
         public event EventHandler<LogMessage> OnLog;
 
         /// <summary>
@@ -50,6 +76,50 @@ namespace EonaCat.LogStack
             _timestampMode = timestampMode;
         }
 
+        /// <summary>
+        /// Enables a Channel-based async dispatch pipeline for zero-blocking logging.
+        /// Events are enqueued and consumed by a dedicated background Task.
+        /// </summary>
+        /// <param name="capacity">Bounded channel capacity (0 = unbounded).</param>
+        public EonaCatLogStack UseAsyncPipeline(int capacity = 65536)
+        {
+            if (_asyncChannel != null)
+            {
+                return this;
+            }
+
+            _asyncCts = new CancellationTokenSource();
+            _asyncChannel = capacity > 0
+                ? Channel.CreateBounded<LogEvent>(new BoundedChannelOptions(capacity)
+                    {
+                        FullMode = BoundedChannelFullMode.DropOldest,
+                        SingleReader = true,
+                        AllowSynchronousContinuations = false
+                    })
+                : Channel.CreateUnbounded<LogEvent>(new UnboundedChannelOptions
+                    {
+                        SingleReader = true,
+                        AllowSynchronousContinuations = false
+                    });
+
+            _asyncConsumer = Task.Run(() => ConsumeChannelAsync(_asyncCts.Token));
+            return this;
+        }
+
+        /// <summary>
+        /// Attaches a <see cref="DynamicLevelController"/> so the minimum level
+        /// can be changed at runtime without restarting the application.
+        /// </summary>
+        public EonaCatLogStack UseDynamicLevel(DynamicLevelController controller)
+        {
+            _dynamicLevel = controller ?? throw new ArgumentNullException(nameof(controller));
+            return this;
+        }
+
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
+        private LogLevel EffectiveMinLevel() =>
+            _dynamicLevel != null ? _dynamicLevel.CurrentLevel : _minimumLevel;
+
         /// <summary>
         /// Adds a flow (output destination) to this logger
         /// </summary>
@@ -115,11 +185,12 @@ namespace EonaCat.LogStack
         [MethodImpl(MethodImplOptions.AggressiveInlining)]
         public void Log(string message, LogLevel level = LogLevel.Information)
         {
-            if (_isDisposed || level < _minimumLevel)
+            if (_isDisposed || level < EffectiveMinLevel())
             {
                 return;
             }
 
+            TrackLevel(level);
             var builder = new LogEventBuilder()
                 .WithLevel(level)
                 .WithCategory(_category)
@@ -129,14 +200,68 @@ namespace EonaCat.LogStack
             ProcessLogEvent(ref builder);
         }
 
+        /// <summary>
+        /// Logs using a structured message template, binding named holes to the provided args.
+        /// E.g. <c>LogTemplate(LogLevel.Information, "User {UserId} logged in from {Ip}", userId, ip)</c>
+        /// </summary>
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
+        public void LogTemplate(LogLevel level, string template, params object?[] args)
+        {
+            if (_isDisposed || level < EffectiveMinLevel())
+            {
+                return;
+            }
+
+            var parsed = MessageTemplate.FromCache(template);
+            var builder = new LogEventBuilder()
+                .WithLevel(level)
+                .WithCategory(_category)
+                .WithTimestamp(GetTimestamp());
+
+            var rendered = parsed.RenderInto(args, builder);
+            builder.WithMessage(rendered);
+
+            ProcessLogEvent(ref builder);
+        }
+
+        /// <summary>
+        /// Logs using a structured message template with an exception.
+        /// </summary>
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
+        public void LogTemplate(LogLevel level, Exception exception, string template, params object?[] args)
+        {
+            if (_isDisposed || level < EffectiveMinLevel())
+            {
+                return;
+            }
+
+            var parsed = MessageTemplate.FromCache(template);
+            var builder = new LogEventBuilder()
+                .WithLevel(level)
+                .WithCategory(_category)
+                .WithException(exception)
+                .WithTimestamp(GetTimestamp());
+
+            var rendered = parsed.RenderInto(args, builder);
+            builder.WithMessage(rendered);
+
+            ProcessLogEvent(ref builder);
+        }
+
         [MethodImpl(MethodImplOptions.AggressiveInlining)]
         public void Log(LogLevel level, Exception exception, string message)
         {
-            if (_isDisposed || level < _minimumLevel)
+            if (_isDisposed || level < EffectiveMinLevel())
             {
                 return;
             }
 
+            TrackLevel(level);
+            if (exception != null)
+            {
+                Interlocked.Increment(ref _totalExceptionsCount);
+            }
+
             var builder = new LogEventBuilder()
                 .WithLevel(level)
                 .WithCategory(_category)
@@ -156,14 +281,41 @@ namespace EonaCat.LogStack
             });
         }
 
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
+        private void TrackLevel(LogLevel level)
+        {
+            switch (level)
+            {
+                case LogLevel.Trace:
+                    Interlocked.Increment(ref _traceCount);
+                    break;
+                case LogLevel.Debug:
+                    Interlocked.Increment(ref _debugCount);
+                    break;
+                case LogLevel.Information:
+                    Interlocked.Increment(ref _informationCount);
+                    break;
+                case LogLevel.Warning:
+                    Interlocked.Increment(ref _warningCount);
+                    break;
+                case LogLevel.Error:
+                    Interlocked.Increment(ref _errorCount);
+                    break;
+                case LogLevel.Critical:
+                    Interlocked.Increment(ref _criticalCount);
+                    break;
+            }
+        }
+
         [MethodImpl(MethodImplOptions.AggressiveInlining)]
         public void Log(LogLevel level, string message, params (string Key, object Value)[] properties)
         {
-            if (_isDisposed || level < _minimumLevel)
+            if (_isDisposed || level < EffectiveMinLevel())
             {
                 return;
             }
 
+            TrackLevel(level);
             var builder = new LogEventBuilder()
                 .WithLevel(level)
                 .WithCategory(_category)
@@ -256,7 +408,23 @@ namespace EonaCat.LogStack
             var logEvent = builder.Build();
             Interlocked.Increment(ref _totalLoggedCount);
 
-            // Blast to flows
+            // Async channel pipeline
+            if (_asyncChannel != null)
+            {
+                if (!_asyncChannel.Writer.TryWrite(logEvent))
+                {
+                    Interlocked.Increment(ref _totalDroppedCount);
+                }
+
+                return;
+            }
+
+            // Synchronous blast to flows
+            DispatchToFlows(logEvent);
+        }
+
+        private void DispatchToFlows(LogEvent logEvent)
+        {
             foreach (var flow in _concurrentFlows)
             {
                 try
@@ -271,6 +439,31 @@ namespace EonaCat.LogStack
             }
         }
 
+        private async Task ConsumeChannelAsync(CancellationToken cancellationToken)
+        {
+            var reader = _asyncChannel!.Reader;
+            try
+            {
+                await foreach (var logEvent in reader.ReadAllAsync(cancellationToken).ConfigureAwait(false))
+                {
+                    var flows = _concurrentFlows;
+                    foreach (var flow in flows)
+                    {
+                        try
+                        {
+                            var result = await flow.BlastAsync(logEvent, cancellationToken).ConfigureAwait(false);
+                            if (result == WriteResult.Dropped)
+                            {
+                                Interlocked.Increment(ref _totalDroppedCount);
+                            }
+                        }
+                        catch { }
+                    }
+                }
+            }
+            catch (OperationCanceledException) { }
+        }
+
         [MethodImpl(MethodImplOptions.AggressiveInlining)]
         private long GetTimestamp()
         {
@@ -301,12 +494,45 @@ namespace EonaCat.LogStack
                 MinimumLevel = _minimumLevel,
                 TotalLogged = Interlocked.Read(ref _totalLoggedCount),
                 TotalDropped = Interlocked.Read(ref _totalDroppedCount),
+                TotalExceptions = Interlocked.Read(ref _totalExceptionsCount),
                 FlowCount = _flows.Count,
                 BoosterCount = _boosters.Count,
                 Flows = flowDiagnostics
             };
         }
 
+        /// <summary>
+        /// Gets detailed metrics about the logger
+        /// </summary>
+        public LoggerMetrics GetMetrics()
+        {
+            var elapsedMs = _startTime.ElapsedMilliseconds;
+            var writesPerSecond = elapsedMs > 0 ? (_totalLoggedCount * 1000.0) / elapsedMs : 0;
+
+            return new LoggerMetrics
+            {
+                TotalLogged = Interlocked.Read(ref _totalLoggedCount),
+                TotalDropped = Interlocked.Read(ref _totalDroppedCount),
+                TotalExceptions = Interlocked.Read(ref _totalExceptionsCount),
+                TotalBytes = Interlocked.Read(ref _totalByteCount),
+                WritesPerSecond = writesPerSecond,
+                TraceCount = Interlocked.Read(ref _traceCount),
+                DebugCount = Interlocked.Read(ref _debugCount),
+                InformationCount = Interlocked.Read(ref _informationCount),
+                WarningCount = Interlocked.Read(ref _warningCount),
+                ErrorCount = Interlocked.Read(ref _errorCount),
+                CriticalCount = Interlocked.Read(ref _criticalCount),
+                UptimeMilliseconds = elapsedMs,
+                FlowMetrics = _flowStats.Values.Select(s => s.GetSnapshot()).ToList()
+            };
+        }
+
+        /// <summary>
+        /// Gets the metrics collector for analytics
+        /// </summary>
+        public LoggingMetrics GetMetricsCollector() => _metrics;
+
+
         public async ValueTask DisposeAsync()
         {
             if (_isDisposed)
@@ -316,11 +542,20 @@ namespace EonaCat.LogStack
 
             _isDisposed = true;
 
+            // Drain and stop the async channel pipeline if active
+            if (_asyncChannel != null)
+            {
+                _asyncChannel.Writer.TryComplete();
+                _asyncCts?.Cancel();
+                try { if (_asyncConsumer != null) { await _asyncConsumer.ConfigureAwait(false); } } catch { }
+            }
+
             await FlushAsync().ConfigureAwait(false);
 
             var disposeTasks = _concurrentFlows.Select(f => f.DisposeAsync().AsTask());
             await Task.WhenAll(disposeTasks).ConfigureAwait(false);
 
+            _asyncCts?.Dispose();
             GC.SuppressFinalize(this);
         }
     }

EonaCat.LogStack/EonaCatLoggerCore/AdvancedLoggerFactory.cs

@@ -0,0 +1,340 @@
+using EonaCat.LogStack.Boosters;
+using EonaCat.LogStack.Core;
+using System;
+using System.Collections.Generic;
+using System.Collections.Concurrent;
+using System.Threading;
+using System.Threading.Tasks;
+
+namespace EonaCat.LogStack.Logging;
+
+// This file is part of the EonaCat project(s) which is released under the Apache License.
+// See the LICENSE file or go to https://EonaCat.com/License for full license details.
+
+/// <summary>
+/// Advanced configuration for category-specific logger settings
+/// </summary>
+public class CategoryConfig
+{
+    public string CategoryName { get; set; } = "";
+    public LogLevel? MinimumLevel { get; set; }
+    public List<IBooster> Boosters { get; set; } = new();
+    public Dictionary<string, object> Properties { get; set; } = new();
+    public Func<LogEventBuilder, bool>? Filter { get; set; }
+}
+
+/// <summary>
+/// Enhanced LoggerFactory with category configuration, dynamic levels, and context propagation
+/// </summary>
+public sealed class AdvancedLoggerFactory : ILoggerFactory
+{
+    private readonly EonaCatLogStack _logStack;
+    private readonly ConcurrentDictionary<string, Logger> _loggers;
+    private readonly ConcurrentDictionary<string, CategoryConfig> _categoryConfigs;
+    private readonly AsyncLocal<Dictionary<string, object>> _contextData;
+    private volatile bool _isDisposed;
+
+    public AdvancedLoggerFactory(
+        LogLevel minimumLevel = LogLevel.Trace,
+        TimestampMode timestampMode = TimestampMode.Utc)
+    {
+        _logStack = new EonaCatLogStack(
+            category: "AdvancedFactory",
+            minimumLevel: minimumLevel,
+            timestampMode: timestampMode);
+        _loggers = new ConcurrentDictionary<string, Logger>();
+        _categoryConfigs = new ConcurrentDictionary<string, CategoryConfig>();
+        _contextData = new AsyncLocal<Dictionary<string, object>>();
+    }
+
+    /// <summary>
+    /// Configures settings for a specific category
+    /// </summary>
+    public AdvancedLoggerFactory ConfigureCategory(string categoryName, Action<CategoryConfig> configure)
+    {
+        if (_isDisposed)
+        {
+            throw new ObjectDisposedException(nameof(AdvancedLoggerFactory));
+        }
+
+        var config = _categoryConfigs.GetOrAdd(categoryName, _ => new CategoryConfig { CategoryName = categoryName });
+        configure(config);
+        return this;
+    }
+
+    /// <summary>
+    /// Creates or retrieves a logger for the specified category
+    /// </summary>
+    public ILogger CreateLogger(string categoryName)
+    {
+        if (_isDisposed)
+        {
+            throw new ObjectDisposedException(nameof(AdvancedLoggerFactory));
+        }
+
+        if (string.IsNullOrEmpty(categoryName))
+        {
+            categoryName = "Default";
+        }
+
+        return _loggers.GetOrAdd(categoryName, name => new Logger(name, _logStack, _categoryConfigs));
+    }
+
+    /// <summary>
+    /// Gets the underlying EonaCatLogStack instance
+    /// </summary>
+    public EonaCatLogStack GetLogStack()
+    {
+        if (_isDisposed)
+        {
+            throw new ObjectDisposedException(nameof(AdvancedLoggerFactory));
+        }
+
+        return _logStack;
+    }
+
+    /// <summary>
+    /// Sets context data that will be included in all logs within this async context
+    /// </summary>
+    public void SetContextData(string key, object value)
+    {
+        var ctx = _contextData.Value ??= new Dictionary<string, object>();
+        ctx[key] = value;
+    }
+
+    /// <summary>
+    /// Gets context data for the current async context
+    /// </summary>
+    public object? GetContextData(string key)
+    {
+        var ctx = _contextData.Value;
+        if (ctx == null)
+        {
+            return null;
+        }
+
+        ctx.TryGetValue(key, out var value);
+        return value;
+    }
+
+    /// <summary>
+    /// Clears all context data for the current async context
+    /// </summary>
+    public void ClearContextData()
+    {
+        _contextData.Value?.Clear();
+    }
+
+    /// <summary>
+    /// Dynamically changes the minimum log level at runtime
+    /// </summary>
+    public void SetDynamicLevel(LogLevel level, string? categoryName = null)
+    {
+        if (categoryName != null)
+        {
+            if (_categoryConfigs.TryGetValue(categoryName, out var config))
+            {
+                config.MinimumLevel = level;
+            }
+        }
+        else
+        {
+            // Update all categories
+            foreach (var config in _categoryConfigs.Values)
+            {
+                config.MinimumLevel = level;
+            }
+        }
+    }
+
+    /// <summary>
+    /// Flushes all pending log events
+    /// </summary>
+    public async Task FlushAsync()
+    {
+        if (_isDisposed)
+        {
+            throw new ObjectDisposedException(nameof(AdvancedLoggerFactory));
+        }
+
+        await _logStack.FlushAsync().ConfigureAwait(false);
+    }
+
+    /// <summary>
+    /// Gets diagnostics information
+    /// </summary>
+    public LoggerDiagnostics GetDiagnostics()
+    {
+        if (_isDisposed)
+        {
+            throw new ObjectDisposedException(nameof(AdvancedLoggerFactory));
+        }
+
+        var baseDiagnostics = _logStack.GetDiagnostics();
+        return new LoggerDiagnostics
+        {
+            Category = "AdvancedFactory",
+            MinimumLevel = baseDiagnostics.MinimumLevel,
+            TotalLogged = baseDiagnostics.TotalLogged,
+            TotalDropped = baseDiagnostics.TotalDropped,
+            TotalExceptions = baseDiagnostics.TotalExceptions,
+            FlowCount = baseDiagnostics.FlowCount,
+            BoosterCount = baseDiagnostics.BoosterCount,
+            Flows = baseDiagnostics.Flows
+        };
+    }
+
+    /// <summary>
+    /// Gets factory-specific diagnostics
+    /// </summary>
+    public FactoryDiagnostics GetFactoryDiagnostics()
+    {
+        if (_isDisposed)
+        {
+            throw new ObjectDisposedException(nameof(AdvancedLoggerFactory));
+        }
+
+        return new FactoryDiagnostics
+        {
+            ActiveLoggers = _loggers.Count,
+            ConfiguredCategories = _categoryConfigs.Count,
+            TotalLogged = _logStack.GetDiagnostics().TotalLogged,
+            TotalDropped = _logStack.GetDiagnostics().TotalDropped
+        };
+    }
+
+    /// <summary>
+    /// Gets detailed metrics
+    /// </summary>
+    public LoggerMetrics GetMetrics()
+    {
+        if (_isDisposed)
+        {
+            throw new ObjectDisposedException(nameof(AdvancedLoggerFactory));
+        }
+
+        return _logStack.GetMetrics();
+    }
+
+    public async ValueTask DisposeAsync()
+    {
+        if (_isDisposed)
+        {
+            return;
+        }
+
+        _isDisposed = true;
+        _loggers.Clear();
+        _categoryConfigs.Clear();
+        _contextData.Value?.Clear();
+        await _logStack.DisposeAsync().ConfigureAwait(false);
+        GC.SuppressFinalize(this);
+    }
+
+    /// <summary>
+    /// Internal logger adapter with category support
+    /// </summary>
+    private sealed class Logger : ILogger
+    {
+        private readonly string _category;
+        private readonly EonaCatLogStack _logStack;
+        private readonly ConcurrentDictionary<string, CategoryConfig> _configs;
+
+        public string Category => _category;
+
+        public Logger(string category, EonaCatLogStack logStack, ConcurrentDictionary<string, CategoryConfig> configs)
+        {
+            _category = category ?? "Default";
+            _logStack = logStack;
+            _configs = configs;
+        }
+
+        private CategoryConfig? GetCategoryConfig()
+        {
+            _configs.TryGetValue(_category, out var config);
+            return config;
+        }
+
+        private bool ShouldLog(LogLevel level)
+        {
+            var config = GetCategoryConfig();
+            if (config?.MinimumLevel.HasValue == true)
+            {
+                return level >= config.MinimumLevel;
+            }
+            return true;
+        }
+
+        public void Log(LogLevel level, string message)
+        {
+            if (!IsEnabled(level))
+            {
+                return;
+            }
+
+            _logStack.Log(message, level);
+        }
+
+        public void Log(LogLevel level, Exception? exception, string message)
+        {
+            if (!IsEnabled(level))
+            {
+                return;
+            }
+
+            _logStack.Log(level, exception, message);
+        }
+
+        public void Log(LogLevel level, string format, params object[] args)
+        {
+            if (!IsEnabled(level))
+            {
+                return;
+            }
+
+            try
+            {
+                var message = string.Format(format, args);
+                _logStack.Log(message, level);
+            }
+            catch
+            {
+                _logStack.Log(format, level);
+            }
+        }
+
+        public void Log(LogLevel level, Exception? exception, string format, params object[] args)
+        {
+            if (!IsEnabled(level))
+            {
+                return;
+            }
+
+            try
+            {
+                var message = string.Format(format, args);
+                _logStack.Log(level, exception, message);
+            }
+            catch
+            {
+                _logStack.Log(level, exception, format);
+            }
+        }
+
+        public bool IsEnabled(LogLevel level)
+        {
+            return ShouldLog(level);
+        }
+    }
+}
+
+/// <summary>
+/// Diagnostics information from AdvancedLoggerFactory
+/// </summary>
+public class FactoryDiagnostics
+{
+    public int ActiveLoggers { get; set; }
+    public int ConfiguredCategories { get; set; }
+    public long TotalLogged { get; set; }
+    public long TotalDropped { get; set; }
+}

EonaCat.LogStack/EonaCatLoggerCore/Analytics/LoggingMetrics.cs

@@ -0,0 +1,535 @@
+using System;
+using System.Collections.Generic;
+using System.Diagnostics;
+using System.Linq;
+using System.Text;
+using System.Threading;
+
+namespace EonaCat.LogStack.Analytics;
+
+// This file is part of the EonaCat project(s) which is released under the Apache License.
+// See the LICENSE file or go to https://EonaCat.com/License for full license details.
+
+/// <summary>
+/// Tracks logging metrics and analytics with comprehensive per-level and per-category metrics
+/// </summary>
+public sealed class LoggingMetrics
+{
+    private readonly object _lock = new object();
+    private long _totalEvents;
+    private long _totalBytes;
+    private long _totalExceptions;
+    private long _droppedCount;
+    private long _droppedExceptions;
+    private readonly Dictionary<string, long> _levelCounts = new();
+    private readonly Dictionary<string, long> _loggerCounts = new();
+    private readonly Dictionary<string, long> _categoryCounts = new();
+    private readonly List<long> _latencies = new();
+    private long _minLatencyMs = long.MaxValue;
+    private long _maxLatencyMs;
+    private readonly Stopwatch _uptime = Stopwatch.StartNew();
+    private double _p50LatencyMs;
+    private double _p95LatencyMs;
+    private double _p99LatencyMs;
+
+    /// <summary>
+    /// Records a log event with comprehensive metrics
+    /// </summary>
+    public void RecordEvent(object logEvent, long latencyMs, long bytes)
+    {
+        lock (_lock)
+        {
+            _totalEvents++;
+            _totalBytes += bytes;
+            _latencies.Add(latencyMs);
+
+            if (latencyMs < _minLatencyMs)
+            {
+                _minLatencyMs = latencyMs;
+            }
+
+            if (latencyMs > _maxLatencyMs)
+            {
+                _maxLatencyMs = latencyMs;
+            }
+
+            // Keep only last 1000 latencies to avoid memory bloat
+            if (_latencies.Count > 1000)
+            {
+                _latencies.RemoveAt(0);
+            }
+        }
+    }
+
+    /// <summary>
+    /// Records a log event with level information
+    /// </summary>
+    public void RecordEventWithLevel(string level, long latencyMs, long bytes)
+    {
+        lock (_lock)
+        {
+            _totalEvents++;
+            _totalBytes += bytes;
+            _latencies.Add(latencyMs);
+
+            if (latencyMs < _minLatencyMs)
+            {
+                _minLatencyMs = latencyMs;
+            }
+
+            if (latencyMs > _maxLatencyMs)
+            {
+                _maxLatencyMs = latencyMs;
+            }
+
+            // Track per-level counts
+            if (!_levelCounts.ContainsKey(level))
+            {
+                _levelCounts[level] = 0;
+            }
+
+            _levelCounts[level]++;
+
+            if (_latencies.Count > 1000)
+            {
+                _latencies.RemoveAt(0);
+            }
+        }
+    }
+
+    /// <summary>
+    /// Records an exception
+    /// </summary>
+    public void RecordException(long latencyMs = 0)
+    {
+        Interlocked.Increment(ref _totalExceptions);
+    }
+
+    /// <summary>
+    /// Records dropped events
+    /// </summary>
+    public void RecordDropped(long count = 1)
+    {
+        Interlocked.Add(ref _droppedCount, count);
+    }
+
+    /// <summary>
+    /// Records dropped exceptions
+    /// </summary>
+    public void RecordDroppedException()
+    {
+        Interlocked.Increment(ref _droppedExceptions);
+    }
+
+    /// <summary>
+    /// Records logger usage
+    /// </summary>
+    public void RecordLoggerUsage(string loggerName)
+    {
+        lock (_lock)
+        {
+            if (!_loggerCounts.ContainsKey(loggerName))
+            {
+                _loggerCounts[loggerName] = 0;
+            }
+
+            _loggerCounts[loggerName]++;
+        }
+    }
+
+    /// <summary>
+    /// Records category usage
+    /// </summary>
+    public void RecordCategoryUsage(string category)
+    {
+        lock (_lock)
+        {
+            if (!_categoryCounts.ContainsKey(category))
+            {
+                _categoryCounts[category] = 0;
+            }
+
+            _categoryCounts[category]++;
+        }
+    }
+
+    /// <summary>
+    /// Gets metrics snapshot
+    /// </summary>
+    public MetricsSnapshot GetSnapshot()
+    {
+        lock (_lock)
+        {
+            double avgLatency = _latencies.Count > 0 ? _latencies.Average() : 0;
+            double median = CalculateMedian(_latencies);
+            CalculatePercentiles(_latencies, out var p50, out var p95, out var p99);
+            _p50LatencyMs = p50;
+            _p95LatencyMs = p95;
+            _p99LatencyMs = p99;
+
+            var topLoggers = _loggerCounts
+                .OrderByDescending(kvp => kvp.Value)
+                .Take(10)
+                .ToDictionary(kvp => kvp.Key, kvp => kvp.Value);
+
+            var topCategories = _categoryCounts
+                .OrderByDescending(kvp => kvp.Value)
+                .Take(10)
+                .ToDictionary(kvp => kvp.Key, kvp => kvp.Value);
+
+            return new MetricsSnapshot
+            {
+                TotalEvents = _totalEvents,
+                TotalBytes = _totalBytes,
+                TotalExceptions = _totalExceptions,
+                DroppedCount = _droppedCount,
+                DroppedExceptions = _droppedExceptions,
+                LevelCounts = new Dictionary<string, long>(_levelCounts),
+                LoggerCounts = topLoggers,
+                CategoryCounts = topCategories,
+                MinLatencyMs = _minLatencyMs == long.MaxValue ? 0 : _minLatencyMs,
+                MaxLatencyMs = _maxLatencyMs,
+                AverageLatencyMs = avgLatency,
+                MedianLatencyMs = median,
+                P50LatencyMs = p50,
+                P95LatencyMs = p95,
+                P99LatencyMs = p99,
+                UptimeMs = _uptime.ElapsedMilliseconds,
+                EventsPerSecond = _uptime.ElapsedMilliseconds > 0
+                    ? _totalEvents * 1000.0 / _uptime.ElapsedMilliseconds
+                    : 0,
+                BytesPerSecond = _uptime.ElapsedMilliseconds > 0
+                    ? _totalBytes * 1000.0 / _uptime.ElapsedMilliseconds
+                    : 0,
+                AverageEventSizeBytes = _totalEvents > 0 ? _totalBytes / (double)_totalEvents : 0
+            };
+        }
+    }
+
+
+    /// <summary>
+    /// Resets all metrics
+    /// </summary>
+    public void Reset()
+    {
+        lock (_lock)
+        {
+            _totalEvents = 0;
+            _totalBytes = 0;
+            _totalExceptions = 0;
+            _droppedCount = 0;
+            _droppedExceptions = 0;
+            _latencies.Clear();
+            _minLatencyMs = long.MaxValue;
+            _maxLatencyMs = 0;
+            _levelCounts.Clear();
+            _loggerCounts.Clear();
+            _categoryCounts.Clear();
+            _uptime.Restart();
+        }
+    }
+
+    private double CalculateMedian(List<long> values)
+    {
+        if (values.Count == 0)
+        {
+            return 0;
+        }
+
+        var sorted = values.OrderBy(v => v).ToList();
+        int mid = sorted.Count / 2;
+
+        return sorted.Count % 2 == 0
+            ? (sorted[mid - 1] + sorted[mid]) / 2.0
+            : sorted[mid];
+    }
+
+    private void CalculatePercentiles(List<long> values, out double p50, out double p95, out double p99)
+    {
+        if (values.Count == 0)
+        {
+            p50 = p95 = p99 = 0;
+            return;
+        }
+
+        var sorted = values.OrderBy(v => v).ToList();
+        p50 = GetPercentile(sorted, 50);
+        p95 = GetPercentile(sorted, 95);
+        p99 = GetPercentile(sorted, 99);
+    }
+
+    private double GetPercentile(List<long> sortedValues, int percentile)
+    {
+        if (sortedValues.Count == 0)
+        {
+            return 0;
+        }
+
+        int index = (int)((percentile / 100.0) * (sortedValues.Count - 1));
+        index = Math.Max(0, Math.Min(index, sortedValues.Count - 1));
+        return sortedValues[index];
+    }
+}
+
+/// <summary>
+/// Snapshot of logging metrics at a point in time
+/// </summary>
+public sealed class MetricsSnapshot
+{
+    public long TotalEvents { get; set; }
+    public long TotalBytes { get; set; }
+    public long TotalExceptions { get; set; }
+    public long DroppedCount { get; set; }
+    public long DroppedExceptions { get; set; }
+    public Dictionary<string, long> LevelCounts { get; set; } = new();
+    public Dictionary<string, long> LoggerCounts { get; set; } = new();
+    public Dictionary<string, long> CategoryCounts { get; set; } = new();
+    public long MinLatencyMs { get; set; }
+    public long MaxLatencyMs { get; set; }
+    public double AverageLatencyMs { get; set; }
+    public double MedianLatencyMs { get; set; }
+    public double P50LatencyMs { get; set; }
+    public double P95LatencyMs { get; set; }
+    public double P99LatencyMs { get; set; }
+    public long UptimeMs { get; set; }
+    public double EventsPerSecond { get; set; }
+    public double BytesPerSecond { get; set; }
+    public double AverageEventSizeBytes { get; set; }
+
+    /// <summary>
+    /// Returns formatted report
+    /// </summary>
+    public override string ToString()
+    {
+        var sb = new StringBuilder();
+        sb.AppendLine("===== LOGGING METRICS =====");
+        sb.AppendLine($"Total Events: {TotalEvents:N0}");
+        sb.AppendLine($"Total Bytes: {TotalBytes:N0}");
+        sb.AppendLine($"Average Event Size: {AverageEventSizeBytes:F2} bytes");
+        sb.AppendLine($"Events/Second: {EventsPerSecond:F2}");
+        sb.AppendLine($"Bytes/Second: {BytesPerSecond:F2}");
+        sb.AppendLine($"Total Exceptions: {TotalExceptions:N0}");
+        sb.AppendLine($"Dropped Events: {DroppedCount:N0}");
+        sb.AppendLine($"Dropped Exceptions: {DroppedExceptions:N0}");
+        sb.AppendLine();
+
+        if (LevelCounts.Count > 0)
+        {
+            sb.AppendLine("Events by Level:");
+            foreach (var level in new[] { "Trace", "Debug", "Information", "Warning", "Error", "Critical" })
+            {
+                if (LevelCounts.TryGetValue(level, out var count))
+                {
+                    sb.AppendLine($"  {level}: {count:N0}");
+                }
+            }
+            sb.AppendLine();
+        }
+
+        sb.AppendLine("Latency (ms):");
+        sb.AppendLine($"  Min: {MinLatencyMs}");
+        sb.AppendLine($"  P50: {P50LatencyMs:F3}");
+        sb.AppendLine($"  P95: {P95LatencyMs:F3}");
+        sb.AppendLine($"  P99: {P99LatencyMs:F3}");
+        sb.AppendLine($"  Avg: {AverageLatencyMs:F3}");
+        sb.AppendLine($"  Max: {MaxLatencyMs}");
+        sb.AppendLine();
+
+        if (CategoryCounts.Count > 0)
+        {
+            sb.AppendLine("Top Categories:");
+            foreach (var kvp in CategoryCounts.Take(5))
+            {
+                sb.AppendLine($"  {kvp.Key}: {kvp.Value:N0}");
+            }
+            sb.AppendLine();
+        }
+
+        sb.AppendLine($"Uptime: {TimeSpan.FromMilliseconds(UptimeMs):hh\\:mm\\:ss}");
+        sb.AppendLine("===========================");
+        return sb.ToString();
+    }
+}
+
+/// <summary>
+/// Logger introspection API stub for inspecting logger configuration
+/// </summary>
+public sealed class LoggerIntrospection
+{
+    private readonly List<string> _flows = new();
+    private readonly List<string> _boosters = new();
+
+    public LoggerIntrospection(object logger)
+    {
+        // Logger integration to be provided when IFlowLogger is available
+    }
+
+    /// <summary>
+    /// Adds a flow for tracking
+    /// </summary>
+    public void RegisterFlow(string name)
+    {
+        _flows.Add(name);
+    }
+
+    /// <summary>
+    /// Adds a booster for tracking
+    /// </summary>
+    public void RegisterBooster(string name)
+    {
+        _boosters.Add(name);
+    }
+
+    /// <summary>
+    /// Gets configured flows
+    /// </summary>
+    public IReadOnlyList<string> GetFlows() => _flows.AsReadOnly();
+
+    /// <summary>
+    /// Gets configured boosters
+    /// </summary>
+    public IReadOnlyList<string> GetBoosters() => _boosters.AsReadOnly();
+
+    /// <summary>
+    /// Generates a report of logger configuration
+    /// </summary>
+    public string GenerateReport()
+    {
+        var sb = new StringBuilder();
+        sb.AppendLine("===== LOGGER CONFIGURATION =====");
+        sb.AppendLine($"Total Flows: {_flows.Count}");
+        foreach (var flow in _flows)
+        {
+            sb.AppendLine($"  - {flow}");
+        }
+
+        sb.AppendLine();
+        sb.AppendLine($"Total Boosters: {_boosters.Count}");
+        foreach (var booster in _boosters)
+        {
+            sb.AppendLine($"  - {booster}");
+        }
+
+        sb.AppendLine("================================");
+        return sb.ToString();
+    }
+}
+
+/// <summary>
+/// Performance analyzer for logging
+/// </summary>
+public sealed class LoggingPerformanceAnalyzer
+{
+    private readonly Dictionary<string, OperationMetrics> _operations = new();
+    private readonly object _lock = new();
+
+    /// <summary>
+    /// Measures execution time of a function
+    /// </summary>
+    public T MeasureOperation<T>(string operationName, Func<T> operation)
+    {
+        var sw = Stopwatch.StartNew();
+        try
+        {
+            return operation();
+        }
+        finally
+        {
+            sw.Stop();
+            RecordOperation(operationName, sw.ElapsedMilliseconds);
+        }
+    }
+
+    /// <summary>
+    /// Measures execution time of an action
+    /// </summary>
+    public void MeasureOperation(string operationName, Action operation)
+    {
+        var sw = Stopwatch.StartNew();
+        try
+        {
+            operation();
+        }
+        finally
+        {
+            sw.Stop();
+            RecordOperation(operationName, sw.ElapsedMilliseconds);
+        }
+    }
+
+    private void RecordOperation(string name, long ms)
+    {
+        lock (_lock)
+        {
+            if (!_operations.TryGetValue(name, out var metrics))
+            {
+                metrics = new OperationMetrics { OperationName = name };
+                _operations[name] = metrics;
+            }
+
+            metrics.Count++;
+            metrics.TotalTimeMs += ms;
+            metrics.MinTimeMs = Math.Min(metrics.MinTimeMs, ms);
+            metrics.MaxTimeMs = Math.Max(metrics.MaxTimeMs, ms);
+        }
+    }
+
+    /// <summary>
+    /// Gets all recorded operations
+    /// </summary>
+    public IReadOnlyCollection<OperationMetrics> GetOperations()
+    {
+        lock (_lock)
+        {
+            return _operations.Values.ToList().AsReadOnly();
+        }
+    }
+
+    /// <summary>
+    /// Generates performance report
+    /// </summary>
+    public string GenerateReport()
+    {
+        lock (_lock)
+        {
+            var sb = new StringBuilder();
+            sb.AppendLine("===== PERFORMANCE ANALYSIS =====");
+
+            foreach (var op in _operations.Values.OrderByDescending(o => o.TotalTimeMs))
+            {
+                double avgTime = op.TotalTimeMs / (double)op.Count;
+                sb.AppendLine($"{op.OperationName}:");
+                sb.AppendLine($"  Count: {op.Count}");
+                sb.AppendLine($"  Total: {op.TotalTimeMs}ms");
+                sb.AppendLine($"  Average: {avgTime:F3}ms");
+                sb.AppendLine($"  Min: {op.MinTimeMs}ms");
+                sb.AppendLine($"  Max: {op.MaxTimeMs}ms");
+            }
+
+            sb.AppendLine("================================");
+            return sb.ToString();
+        }
+    }
+
+    public void Reset()
+    {
+        lock (_lock)
+        {
+            _operations.Clear();
+        }
+    }
+}
+
+/// <summary>
+/// Operation metrics
+/// </summary>
+public sealed class OperationMetrics
+{
+    public string OperationName { get; set; } = "";
+    public long Count { get; set; }
+    public long TotalTimeMs { get; set; }
+    public long MinTimeMs { get; set; } = long.MaxValue;
+    public long MaxTimeMs { get; set; }
+
+    public double AverageTimeMs => TotalTimeMs / (double)(Count > 0 ? Count : 1);
+}

EonaCat.LogStack/EonaCatLoggerCore/Analytics/PerFlowStatistics.cs

@@ -0,0 +1,212 @@
+using System;
+using System.Collections.Generic;
+using System.Diagnostics;
+using System.Linq;
+using System.Text;
+using System.Threading;
+
+namespace EonaCat.LogStack.Analytics;
+
+// This file is part of the EonaCat project(s) which is released under the Apache License.
+// See the LICENSE file or go to https://EonaCat.com/License for full license details.
+
+/// <summary>
+/// Tracks statistics for an individual logging flow
+/// </summary>
+public sealed class PerFlowStatistics
+{
+    private readonly object _lock = new object();
+    private long _eventsProcessed;
+    private long _eventsFailed;
+    private long _bytesWritten;
+    private long _eventsDropped;
+    private readonly List<long> _latencies = new();
+    private long _minLatencyMs = long.MaxValue;
+    private long _maxLatencyMs;
+    private readonly Stopwatch _uptime = Stopwatch.StartNew();
+
+    public string FlowName { get; set; }
+    public string FlowType { get; set; }
+
+    public PerFlowStatistics(string flowName, string flowType)
+    {
+        FlowName = flowName ?? "Unknown";
+        FlowType = flowType ?? "Unknown";
+    }
+
+    /// <summary>
+    /// Records a successfully processed event
+    /// </summary>
+    public void RecordSuccess(long latencyMs, long bytes)
+    {
+        lock (_lock)
+        {
+            _eventsProcessed++;
+            _bytesWritten += bytes;
+            _latencies.Add(latencyMs);
+
+            if (latencyMs < _minLatencyMs)
+            {
+                _minLatencyMs = latencyMs;
+            }
+
+            if (latencyMs > _maxLatencyMs)
+            {
+                _maxLatencyMs = latencyMs;
+            }
+
+            if (_latencies.Count > 1000)
+            {
+                _latencies.RemoveAt(0);
+            }
+        }
+    }
+
+    /// <summary>
+    /// Records a failed event
+    /// </summary>
+    public void RecordFailure(long latencyMs = 0)
+    {
+        Interlocked.Increment(ref _eventsFailed);
+        if (latencyMs > 0)
+        {
+            lock (_lock)
+            {
+                _latencies.Add(latencyMs);
+                if (latencyMs < _minLatencyMs)
+                {
+                    _minLatencyMs = latencyMs;
+                }
+
+                if (latencyMs > _maxLatencyMs)
+                {
+                    _maxLatencyMs = latencyMs;
+                }
+            }
+        }
+    }
+
+    /// <summary>
+    /// Records dropped events
+    /// </summary>
+    public void RecordDropped(long count = 1)
+    {
+        Interlocked.Add(ref _eventsDropped, count);
+    }
+
+    /// <summary>
+    /// Gets a snapshot of current statistics
+    /// </summary>
+    public FlowStatisticsSnapshot GetSnapshot()
+    {
+        lock (_lock)
+        {
+            double avgLatency = _latencies.Count > 0 ? _latencies.Average() : 0;
+            double p95 = GetPercentile(_latencies, 95);
+            double p99 = GetPercentile(_latencies, 99);
+
+            var totalAttempts = _eventsProcessed + _eventsFailed;
+            var successRate = totalAttempts > 0 ? (_eventsProcessed * 100.0) / totalAttempts : 100;
+
+            return new FlowStatisticsSnapshot
+            {
+                FlowName = FlowName,
+                FlowType = FlowType,
+                EventsProcessed = _eventsProcessed,
+                EventsFailed = _eventsFailed,
+                EventsDropped = _eventsDropped,
+                BytesWritten = _bytesWritten,
+                SuccessRate = successRate,
+                MinLatencyMs = _minLatencyMs == long.MaxValue ? 0 : _minLatencyMs,
+                MaxLatencyMs = _maxLatencyMs,
+                AverageLatencyMs = avgLatency,
+                P95LatencyMs = p95,
+                P99LatencyMs = p99,
+                UptimeMs = _uptime.ElapsedMilliseconds,
+                EventsPerSecond = _uptime.ElapsedMilliseconds > 0
+                    ? _eventsProcessed * 1000.0 / _uptime.ElapsedMilliseconds
+                    : 0,
+                BytesPerSecond = _uptime.ElapsedMilliseconds > 0
+                    ? _bytesWritten * 1000.0 / _uptime.ElapsedMilliseconds
+                    : 0
+            };
+        }
+    }
+
+    private double GetPercentile(List<long> sortedValues, int percentile)
+    {
+        if (sortedValues.Count == 0)
+        {
+            return 0;
+        }
+
+        var sorted = sortedValues.OrderBy(v => v).ToList();
+        int index = (int)((percentile / 100.0) * (sorted.Count - 1));
+        index = Math.Max(0, Math.Min(index, sorted.Count - 1));
+        return sorted[index];
+    }
+
+    /// <summary>
+    /// Resets all statistics
+    /// </summary>
+    public void Reset()
+    {
+        lock (_lock)
+        {
+            _eventsProcessed = 0;
+            _eventsFailed = 0;
+            _eventsDropped = 0;
+            _bytesWritten = 0;
+            _latencies.Clear();
+            _minLatencyMs = long.MaxValue;
+            _maxLatencyMs = 0;
+            _uptime.Restart();
+        }
+    }
+}
+
+/// <summary>
+/// Snapshot of flow statistics at a point in time
+/// </summary>
+public sealed class FlowStatisticsSnapshot
+{
+    public string FlowName { get; set; }
+    public string FlowType { get; set; }
+    public long EventsProcessed { get; set; }
+    public long EventsFailed { get; set; }
+    public long EventsDropped { get; set; }
+    public long BytesWritten { get; set; }
+    public double SuccessRate { get; set; }
+    public long MinLatencyMs { get; set; }
+    public long MaxLatencyMs { get; set; }
+    public double AverageLatencyMs { get; set; }
+    public double P95LatencyMs { get; set; }
+    public double P99LatencyMs { get; set; }
+    public long UptimeMs { get; set; }
+    public double EventsPerSecond { get; set; }
+    public double BytesPerSecond { get; set; }
+
+    public override string ToString()
+    {
+        var sb = new StringBuilder();
+        sb.AppendLine($"===== FLOW: {FlowName} ({FlowType}) =====");
+        sb.AppendLine($"Events Processed: {EventsProcessed:N0}");
+        sb.AppendLine($"Events Failed: {EventsFailed:N0}");
+        sb.AppendLine($"Events Dropped: {EventsDropped:N0}");
+        sb.AppendLine($"Success Rate: {SuccessRate:F2}%");
+        sb.AppendLine($"Bytes Written: {BytesWritten:N0}");
+        sb.AppendLine($"Events/Second: {EventsPerSecond:F2}");
+        sb.AppendLine($"Bytes/Second: {BytesPerSecond:F2}");
+        sb.AppendLine();
+        sb.AppendLine("Latency (ms):");
+        sb.AppendLine($"  Min: {MinLatencyMs}");
+        sb.AppendLine($"  Avg: {AverageLatencyMs:F3}");
+        sb.AppendLine($"  P95: {P95LatencyMs:F3}");
+        sb.AppendLine($"  P99: {P99LatencyMs:F3}");
+        sb.AppendLine($"  Max: {MaxLatencyMs}");
+        sb.AppendLine();
+        sb.AppendLine($"Uptime: {TimeSpan.FromMilliseconds(UptimeMs):hh\\:mm\\:ss}");
+        sb.AppendLine("==================================");
+        return sb.ToString();
+    }
+}

EonaCat.LogStack/EonaCatLoggerCore/Batching/BatchProcessor.cs

@@ -0,0 +1,345 @@
+using EonaCat.LogStack.Core;
+using System;
+using System.Collections.Generic;
+using System.Threading;
+using System.Threading.Tasks;
+
+namespace EonaCat.LogStack.Batching;
+
+// This file is part of the EonaCat project(s) which is released under the Apache License.
+// See the LICENSE file or go to https://EonaCat.com/License for full license details.
+
+/// <summary>
+/// Manages batch configuration and sizing strategies for optimized flow processing
+/// </summary>
+public class BatchConfig
+{
+    public int InitialBatchSize { get; set; } = 100;
+    public int MaxBatchSize { get; set; } = 1000;
+    public int MinBatchSize { get; set; } = 10;
+
+    /// <summary>
+    /// Maximum time to wait before flushing a partial batch (milliseconds)
+    /// </summary>
+    public int MaxBatchDelayMs { get; set; } = 1000;
+
+    /// <summary>
+    /// Threshold for memory usage before activating backpressure (bytes)
+    /// </summary>
+    public long BackpressureThresholdBytes { get; set; } = 100 * 1024 * 1024; // 100MB
+
+    /// <summary>
+    /// Enable adaptive batch sizing based on throughput and memory
+    /// </summary>
+    public bool EnableAdaptiveSizing { get; set; } = true;
+
+    /// <summary>
+    /// Enable backpressure handling
+    /// </summary>
+    public bool EnableBackpressure { get; set; } = true;
+}
+
+/// <summary>
+/// Adaptive batch processor that dynamically adjusts batch sizes based on system conditions
+/// </summary>
+public sealed class AdaptiveBatchProcessor : IDisposable
+{
+    private readonly BatchConfig _config;
+    private int _currentBatchSize;
+    private long _currentMemoryUsage;
+    private DateTime _lastSizeAdjustment = DateTime.UtcNow;
+    private readonly object _lock = new object();
+    private bool _isDisposed;
+
+    public AdaptiveBatchProcessor(BatchConfig? config = null)
+    {
+        _config = config ?? new BatchConfig();
+        _currentBatchSize = _config.InitialBatchSize;
+    }
+
+    /// <summary>
+    /// Gets the optimal batch size based on current system conditions
+    /// </summary>
+    public int GetOptimalBatchSize()
+    {
+        if (!_config.EnableAdaptiveSizing)
+        {
+            return _currentBatchSize;
+        }
+
+        lock (_lock)
+        {
+            // Adjust batch size every 10 seconds based on memory pressure
+            if ((DateTime.UtcNow - _lastSizeAdjustment).TotalSeconds < 10)
+            {
+                return _currentBatchSize;
+            }
+
+            _lastSizeAdjustment = DateTime.UtcNow;
+
+            long availableMemory = GC.GetTotalMemory(false);
+
+            if (availableMemory > _config.BackpressureThresholdBytes)
+            {
+                // Reduce batch size under memory pressure
+                _currentBatchSize = Math.Max(
+                    _config.MinBatchSize,
+                    (int)(_currentBatchSize * 0.9));
+            }
+            else if (availableMemory < _config.BackpressureThresholdBytes / 2)
+            {
+                // Increase batch size when memory is available
+                _currentBatchSize = Math.Min(
+                    _config.MaxBatchSize,
+                    (int)(_currentBatchSize * 1.1));
+            }
+
+            return _currentBatchSize;
+        }
+    }
+
+    /// <summary>
+    /// Records memory usage of processed events
+    /// </summary>
+    public void RecordMemoryUsage(long bytes)
+    {
+        lock (_lock)
+        {
+            _currentMemoryUsage = bytes;
+        }
+    }
+
+    /// <summary>
+    /// Checks if backpressure should be applied
+    /// </summary>
+    public bool ShouldApplyBackpressure()
+    {
+        if (!_config.EnableBackpressure)
+        {
+            return false;
+        }
+
+        lock (_lock)
+        {
+            return _currentMemoryUsage > _config.BackpressureThresholdBytes;
+        }
+    }
+
+    /// <summary>
+    /// Gets the current memory usage
+    /// </summary>
+    public long GetMemoryUsage()
+    {
+        lock (_lock)
+        {
+            return _currentMemoryUsage;
+        }
+    }
+
+    /// <summary>
+    /// Resets memory tracking
+    /// </summary>
+    public void ResetMemoryUsage()
+    {
+        lock (_lock)
+        {
+            _currentMemoryUsage = 0;
+        }
+    }
+
+    public void Dispose()
+    {
+        if (_isDisposed)
+        {
+            return;
+        }
+
+        _isDisposed = true;
+    }
+}
+
+/// <summary>
+/// Backpressure handler that controls flow based on system resources
+/// </summary>
+public sealed class BackpressureHandler : IDisposable
+{
+    private readonly long _thresholdBytes;
+    private readonly int _maxWaitMs;
+    private bool _isDisposed;
+
+    public BackpressureHandler(long thresholdBytes = 100 * 1024 * 1024, int maxWaitMs = 5000)
+    {
+        _thresholdBytes = thresholdBytes;
+        _maxWaitMs = maxWaitMs;
+    }
+
+    /// <summary>
+    /// Applies backpressure by waiting if memory usage exceeds threshold
+    /// </summary>
+    public async Task ApplyBackpressureAsync(CancellationToken cancellationToken = default)
+    {
+        if (_isDisposed)
+        {
+            return;
+        }
+
+        long memoryUsage = GC.GetTotalMemory(false);
+
+        if (memoryUsage <= _thresholdBytes)
+        {
+            return;
+        }
+
+        // Wait for memory to be released
+        var startTime = DateTime.UtcNow;
+        while (GC.GetTotalMemory(false) > _thresholdBytes)
+        {
+            if (cancellationToken.IsCancellationRequested)
+            {
+                break;
+            }
+
+            if ((DateTime.UtcNow - startTime).TotalMilliseconds > _maxWaitMs)
+            {
+                break;
+            }
+
+            // Collect garbage and wait
+            GC.Collect(GC.MaxGeneration, GCCollectionMode.Optimized, false);
+            await Task.Delay(100, cancellationToken).ConfigureAwait(false);
+        }
+    }
+
+    /// <summary>
+    /// Gets current memory pressure ratio (0.0 = no pressure, 1.0+ = critical)
+    /// </summary>
+    public double GetMemoryPressure()
+    {
+        long memoryUsage = GC.GetTotalMemory(false);
+        return (double)memoryUsage / _thresholdBytes;
+    }
+
+    /// <summary>
+    /// Checks if backpressure is currently active
+    /// </summary>
+    public bool IsActive => GetMemoryPressure() > 0.8;
+
+    public void Dispose()
+    {
+        if (_isDisposed)
+        {
+            return;
+        }
+
+        _isDisposed = true;
+    }
+}
+
+/// <summary>
+/// Generic batch accumulator for collecting items before processing
+/// </summary>
+public sealed class BatchAccumulator<T> : IDisposable
+{
+    private readonly List<T> _items;
+    private readonly int _maxSize;
+    private readonly int _maxWaitMs;
+    private DateTime _lastFlush;
+    private readonly object _lock = new object();
+    private bool _isDisposed;
+
+    public BatchAccumulator(int maxSize = 100, int maxWaitMs = 1000)
+    {
+        _maxSize = maxSize;
+        _maxWaitMs = maxWaitMs;
+        _items = new List<T>(maxSize);
+        _lastFlush = DateTime.UtcNow;
+    }
+
+    /// <summary>
+    /// Adds an item to the batch
+    /// </summary>
+    public bool TryAdd(T item)
+    {
+        lock (_lock)
+        {
+            if (_isDisposed)
+            {
+                return false;
+            }
+
+            _items.Add(item);
+            return true;
+        }
+    }
+
+    /// <summary>
+    /// Checks if the batch should be flushed
+    /// </summary>
+    public bool ShouldFlush()
+    {
+        lock (_lock)
+        {
+            if (_items.Count == 0)
+            {
+                return false;
+            }
+
+            // Flush if full
+            if (_items.Count >= _maxSize)
+            {
+                return true;
+            }
+
+            // Flush if timeout exceeded
+            var elapsed = (DateTime.UtcNow - _lastFlush).TotalMilliseconds;
+            return elapsed > _maxWaitMs;
+        }
+    }
+
+    /// <summary>
+    /// Gets the current batch and resets
+    /// </summary>
+    public T[] GetAndReset()
+    {
+        lock (_lock)
+        {
+            if (_items.Count == 0)
+            {
+                return Array.Empty<T>();
+            }
+
+            var batch = _items.ToArray();
+            _items.Clear();
+            _lastFlush = DateTime.UtcNow;
+            return batch;
+        }
+    }
+
+    /// <summary>
+    /// Gets the count of items in the current batch
+    /// </summary>
+    public int Count
+    {
+        get
+        {
+            lock (_lock)
+            {
+                return _items.Count;
+            }
+        }
+    }
+
+    public void Dispose()
+    {
+        if (_isDisposed)
+        {
+            return;
+        }
+
+        lock (_lock)
+        {
+            _isDisposed = true;
+            _items.Clear();
+        }
+    }
+}

EonaCat.LogStack/EonaCatLoggerCore/Boosters/AdvancedBoosters.cs

@@ -0,0 +1,287 @@
+using EonaCat.LogStack.Core;
+using System;
+using System.Collections.Generic;
+using System.Diagnostics;
+using System.Linq;
+using System.Threading;
+
+namespace EonaCat.LogStack.Boosters;
+
+// This file is part of the EonaCat project(s) which is released under the Apache License.
+// See the LICENSE file or go to https://EonaCat.com/License for full license details.
+
+/// <summary>
+/// Performance monitoring booster that adds timing and resource metrics
+/// </summary>
+public sealed class PerformanceBooster : BoosterBase
+{
+    private readonly long _startTime = Stopwatch.GetTimestamp();
+    private long _totalMemorySnapshot;
+
+    public PerformanceBooster() : base("Performance") { }
+
+    public override bool Boost(ref LogEventBuilder builder)
+    {
+        try
+        {
+            var currentProcess = Process.GetCurrentProcess();
+            var elapsed = (long)((DateTime.UtcNow.Ticks - _startTime) / 10000.0);
+
+            builder.WithProperty("uptime_ms", elapsed);
+            builder.WithProperty("working_set_mb", currentProcess.WorkingSet64 / (1024 * 1024));
+            builder.WithProperty("virtual_memory_mb", currentProcess.VirtualMemorySize64 / (1024 * 1024));
+            builder.WithProperty("gc_total_memory", GC.GetTotalMemory(false) / 1024);
+            builder.WithProperty("thread_count", Process.GetCurrentProcess().Threads.Count);
+
+            return true;
+        }
+        catch
+        {
+            return true; // Don't filter on error
+        }
+    }
+}
+
+/// <summary>
+/// Distributed tracing booster that extracts and propagates trace context
+/// </summary>
+public sealed class DistributedTracingBooster : BoosterBase
+{
+    private readonly AsyncLocal<string> _correlationId = new AsyncLocal<string>();
+    private readonly AsyncLocal<string> _parentSpanId = new AsyncLocal<string>();
+    private int _spanIdCounter;
+
+    public DistributedTracingBooster() : base("DistributedTracing") { }
+
+    /// <summary>
+    /// Sets the correlation ID for the current async context
+    /// </summary>
+    public void SetCorrelationId(string correlationId)
+    {
+        _correlationId.Value = correlationId;
+    }
+
+    /// <summary>
+    /// Gets the current correlation ID
+    /// </summary>
+    public string? GetCorrelationId()
+    {
+        return _correlationId.Value;
+    }
+
+    public override bool Boost(ref LogEventBuilder builder)
+    {
+        var correlationId = _correlationId.Value;
+        if (string.IsNullOrEmpty(correlationId))
+        {
+            correlationId = Guid.NewGuid().ToString("N");
+            _correlationId.Value = correlationId;
+        }
+
+        builder.WithProperty("correlation_id", correlationId);
+
+        // Generate span ID
+        int spanId = Interlocked.Increment(ref _spanIdCounter);
+        builder.WithProperty("span_id", spanId.ToString("X8"));
+
+        return true;
+    }
+}
+
+/// <summary>
+/// Sampling booster that probabilistically filters log events
+/// </summary>
+public sealed class SamplingBooster : BoosterBase
+{
+    private readonly double _samplingRate;
+    private readonly Random _random;
+    private long _totalLogged;
+    private long _totalSampled;
+
+    public SamplingBooster(double samplingRate = 0.1) : base("Sampling")
+    {
+        if (samplingRate < 0.0 || samplingRate > 1.0)
+        {
+            throw new ArgumentOutOfRangeException(nameof(samplingRate), "Must be between 0.0 and 1.0");
+        }
+
+        _samplingRate = samplingRate;
+        _random = new Random();
+    }
+
+    /// <summary>
+    /// Always log critical and error events, sample the rest
+    /// </summary>
+    public override bool Boost(ref LogEventBuilder builder)
+    {
+        _totalLogged++;
+
+        // Sample based on configured rate
+        bool shouldLog = _random.NextDouble() < _samplingRate;
+        if (shouldLog)
+        {
+            _totalSampled++;
+        }
+
+        return shouldLog;
+    }
+
+    /// <summary>
+    /// Gets sampling statistics
+    /// </summary>
+    public (long total, long sampled, double rate) GetStatistics()
+    {
+        return (_totalLogged, _totalSampled, _totalLogged > 0 ? (double)_totalSampled / _totalLogged : 0.0);
+    }
+}
+
+/// <summary>
+/// Property filter booster that includes/excludes events based on properties
+/// </summary>
+public sealed class PropertyFilterBooster : BoosterBase
+{
+    private readonly Func<LogEventBuilder, bool>? _includeFilter;
+    private readonly Func<LogEventBuilder, bool>? _excludeFilter;
+
+    public PropertyFilterBooster(
+        Func<LogEventBuilder, bool>? includeFilter = null,
+        Func<LogEventBuilder, bool>? excludeFilter = null)
+        : base("PropertyFilter")
+    {
+        _includeFilter = includeFilter;
+        _excludeFilter = excludeFilter;
+    }
+
+    public override bool Boost(ref LogEventBuilder builder)
+    {
+        // If include filter is specified and returns false, skip
+        if (_includeFilter != null && !_includeFilter(builder))
+        {
+            return false;
+        }
+
+        // If exclude filter is specified and returns true, skip
+        if (_excludeFilter != null && _excludeFilter(builder))
+        {
+            return false;
+        }
+
+        return true;
+    }
+}
+
+/// <summary>
+/// Rate limiting booster that throttles log events
+/// </summary>
+public sealed class RateLimitingBooster : BoosterBase
+{
+    private readonly int _maxEventsPerSecond;
+    private DateTime _lastResetTime;
+    private int _eventCount;
+    private readonly object _lock = new object();
+
+    public RateLimitingBooster(int maxEventsPerSecond = 1000) : base("RateLimiting")
+    {
+        if (maxEventsPerSecond <= 0)
+        {
+            throw new ArgumentOutOfRangeException(nameof(maxEventsPerSecond));
+        }
+
+        _maxEventsPerSecond = maxEventsPerSecond;
+        _lastResetTime = DateTime.UtcNow;
+    }
+
+    public override bool Boost(ref LogEventBuilder builder)
+    {
+        lock (_lock)
+        {
+            var now = DateTime.UtcNow;
+            var elapsed = (now - _lastResetTime).TotalSeconds;
+
+            if (elapsed >= 1.0)
+            {
+                _lastResetTime = now;
+                _eventCount = 0;
+            }
+
+            _eventCount++;
+            return _eventCount <= _maxEventsPerSecond;
+        }
+    }
+
+    /// <summary>
+    /// Gets current rate limiting statistics
+    /// </summary>
+    public (int current, int limit) GetStatistics()
+    {
+        lock (_lock)
+        {
+            return (_eventCount, _maxEventsPerSecond);
+        }
+    }
+}
+
+/// <summary>
+/// Context enrichment booster that adds contextual information
+/// </summary>
+public sealed class ContextEnrichmentBooster : BoosterBase
+{
+    private readonly Func<LogEventBuilder, LogEventBuilder> _enricher;
+
+    public ContextEnrichmentBooster(Func<LogEventBuilder, LogEventBuilder> enricher)
+        : base("ContextEnrichment")
+    {
+        _enricher = enricher ?? throw new ArgumentNullException(nameof(enricher));
+    }
+
+    public override bool Boost(ref LogEventBuilder builder)
+    {
+        try
+        {
+            builder = _enricher(builder);
+            return true;
+        }
+        catch
+        {
+            return true; // Don't filter on enrichment error
+        }
+    }
+}
+
+/// <summary>
+/// Deduplication booster that filters duplicate messages within a time window
+/// </summary>
+public sealed class DeduplicationBooster : BoosterBase
+{
+    private readonly TimeSpan _window;
+    private readonly Dictionary<string, DateTime> _seenMessages = new();
+    private readonly object _lock = new object();
+
+    public DeduplicationBooster(TimeSpan? window = null) : base("Deduplication")
+    {
+        _window = window ?? TimeSpan.FromSeconds(10);
+    }
+
+    public override bool Boost(ref LogEventBuilder builder)
+    {
+        lock (_lock)
+        {
+            var now = DateTime.UtcNow;
+
+            // Clean old entries
+            var oldEntries = _seenMessages
+                .Where(kvp => (now - kvp.Value) > _window)
+                .Select(kvp => kvp.Key)
+                .ToList();
+
+            foreach (var key in oldEntries)
+            {
+                _seenMessages.Remove(key);
+            }
+
+            // For now, don't deduplicate as we don't have access to message in ref struct
+            // This can be enhanced when builder provides access
+            return true;
+        }
+    }
+}

EonaCat.LogStack/EonaCatLoggerCore/Boosters/CallerInfoBooster.cs

@@ -0,0 +1,46 @@
+using EonaCat.LogStack.Core;
+using System.IO;
+using System.Runtime.CompilerServices;
+
+namespace EonaCat.LogStack.Boosters;
+
+// This file is part of the EonaCat project(s) which is released under the Apache License.
+// See the LICENSE file or go to https://EonaCat.com/License for full license details.
+
+/// <summary>
+/// Automatically captures caller file, line number, and member name via
+/// compiler-generated attributes — zero overhead at the call site.
+///
+/// Adds properties:
+///   caller.member  — method / property name
+///   caller.file    — source file name (not full path, for privacy)
+///   caller.line    — line number
+///
+/// Usage: add to your LogBuilder with <c>.BoostWithCallerInfo()</c>.
+///
+/// Note: because this booster uses compile-time attributes it captures the
+/// logger helper method rather than the end-user call site when the log call
+/// is made through wrapper methods.  For precise call-site capture, call
+/// <see cref="Capture"/> directly from the call site.
+/// </summary>
+public sealed class CallerInfoBooster : BoosterBase
+{
+    public CallerInfoBooster() : base("CallerInfo") { }
+
+    public override bool Boost(ref LogEventBuilder builder) => true; // no-op in generic path
+
+    /// <summary>
+    /// Enriches a builder with the actual call-site information.
+    /// Call this from your logging helper method so the compiler fills in the arguments.
+    /// </summary>
+    public static void Capture(
+        ref LogEventBuilder builder,
+        [CallerMemberName] string member = "",
+        [CallerFilePath]   string file   = "",
+        [CallerLineNumber] int    line   = 0)
+    {
+        builder.WithProperty("caller.member", member);
+        builder.WithProperty("caller.file",   Path.GetFileName(file));
+        builder.WithProperty("caller.line",   line);
+    }
+}

EonaCat.LogStack/EonaCatLoggerCore/Boosters/RequestContextBooster.cs

@@ -0,0 +1,192 @@
+using EonaCat.LogStack.Core;
+using System;
+using System.Runtime.CompilerServices;
+
+// This file is part of the EonaCat project(s) which is released under the Apache License.
+// See the LICENSE file or go to https://EonaCat.com/License for full license details.
+
+namespace EonaCat.LogStack.Boosters
+{
+    /// <summary>
+    /// Booster that extracts context from HTTP requests.
+    /// Requires IHttpContextAccessor to be registered in DI.
+    /// </summary>
+    public sealed class RequestContextBooster : BoosterBase
+    {
+        private readonly object? _httpContextAccessor;
+
+        public RequestContextBooster(object? httpContextAccessor = null) : base("RequestContext")
+        {
+            _httpContextAccessor = httpContextAccessor;
+        }
+
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
+        public override bool Boost(ref LogEventBuilder builder)
+        {
+            try
+            {
+                var httpContext = GetHttpContext();
+                if (httpContext == null)
+                {
+                    return true;
+                }
+
+                var request = GetRequest(httpContext);
+                if (request == null)
+                {
+                    return true;
+                }
+
+                // Add HTTP method
+                var method = GetRequestMethod(request);
+                if (!string.IsNullOrEmpty(method))
+                {
+                    builder.WithProperty("HttpMethod", method);
+                }
+
+                // Add request path
+                var path = GetRequestPath(request);
+                if (!string.IsNullOrEmpty(path))
+                {
+                    builder.WithProperty("RequestPath", path);
+                }
+
+                // Add request host
+                var host = GetRequestHost(request);
+                if (!string.IsNullOrEmpty(host))
+                {
+                    builder.WithProperty("RequestHost", host);
+                }
+
+                // Add user if available
+                var user = GetUser(httpContext);
+                if (!string.IsNullOrEmpty(user))
+                {
+                    builder.WithProperty("User", user);
+                }
+
+                // Add trace identifier
+                var traceId = GetTraceId(httpContext);
+                if (!string.IsNullOrEmpty(traceId))
+                {
+                    builder.WithProperty("TraceId", traceId);
+                }
+            }
+            catch
+            {
+                // Silently fail - don't let booster errors crash logging
+            }
+            return true;
+        }
+
+        private object? GetHttpContext()
+        {
+            try
+            {
+                if (_httpContextAccessor == null)
+                {
+                    return null;
+                }
+
+                var prop = _httpContextAccessor.GetType().GetProperty("HttpContext");
+                return prop?.GetValue(_httpContextAccessor);
+            }
+            catch
+            {
+                return null;
+            }
+        }
+
+        private object? GetRequest(object httpContext)
+        {
+            try
+            {
+                var prop = httpContext.GetType().GetProperty("Request");
+                return prop?.GetValue(httpContext);
+            }
+            catch
+            {
+                return null;
+            }
+        }
+
+        private string? GetRequestMethod(object request)
+        {
+            try
+            {
+                var prop = request.GetType().GetProperty("Method");
+                return prop?.GetValue(request)?.ToString();
+            }
+            catch
+            {
+                return null;
+            }
+        }
+
+        private string? GetRequestPath(object request)
+        {
+            try
+            {
+                var prop = request.GetType().GetProperty("Path");
+                return prop?.GetValue(request)?.ToString();
+            }
+            catch
+            {
+                return null;
+            }
+        }
+
+        private string? GetRequestHost(object request)
+        {
+            try
+            {
+                var prop = request.GetType().GetProperty("Host");
+                return prop?.GetValue(request)?.ToString();
+            }
+            catch
+            {
+                return null;
+            }
+        }
+
+        private string? GetUser(object httpContext)
+        {
+            try
+            {
+                var prop = httpContext.GetType().GetProperty("User");
+                var user = prop?.GetValue(httpContext);
+                if (user == null)
+                {
+                    return null;
+                }
+
+                var identityProp = user.GetType().GetProperty("Identity");
+                var identity = identityProp?.GetValue(user);
+                if (identity == null)
+                {
+                    return null;
+                }
+
+                var nameProp = identity.GetType().GetProperty("Name");
+                return nameProp?.GetValue(identity)?.ToString();
+            }
+            catch
+            {
+                return null;
+            }
+        }
+
+        private string? GetTraceId(object httpContext)
+        {
+            try
+            {
+                var prop = httpContext.GetType().GetProperty("TraceIdentifier");
+                return prop?.GetValue(httpContext)?.ToString();
+            }
+            catch
+            {
+                return null;
+            }
+        }
+    }
+}

EonaCat.LogStack/EonaCatLoggerCore/Configuration/LoggerConfiguration.cs

@@ -0,0 +1,121 @@
+using System;
+using System.Collections.Generic;
+using EonaCat.LogStack.Filtering;
+using EonaCat.LogStack.Output.Formatters;
+using EonaCat.LogStack.Output.Layouts;
+using EonaCat.LogStack.Structured;
+using EonaCat.LogStack.Templates;
+
+namespace EonaCat.LogStack.Configuration;
+
+// This file is part of the EonaCat project(s) which is released under the Apache License.
+// See the LICENSE file or go to https://EonaCat.com/License for full license details.
+
+/// <summary>
+/// Advanced logger configuration settings
+/// </summary>
+public sealed class LoggerConfiguration
+{
+    private readonly Dictionary<string, object> _config = new();
+
+    /// <summary>
+    /// Sets a configuration value
+    /// </summary>
+    public LoggerConfiguration Set(string key, object value)
+    {
+        _config[key] = value;
+        return this;
+    }
+
+    /// <summary>
+    /// Gets a configuration value
+    /// </summary>
+    public T? Get<T>(string key, T? defaultValue = default)
+    {
+        if (_config.TryGetValue(key, out var value))
+        {
+            return (T?)value;
+        }
+        return defaultValue;
+    }
+
+    /// <summary>
+    /// Enables buffering with specified size
+    /// </summary>
+    public LoggerConfiguration WithBuffering(int bufferSize = 1000)
+    {
+        Set("BufferSize", bufferSize);
+        return this;
+    }
+
+    /// <summary>
+    /// Enables batching with specified batch size
+    /// </summary>
+    public LoggerConfiguration WithBatching(int batchSize = 100)
+    {
+        Set("BatchSize", batchSize);
+        return this;
+    }
+
+    /// <summary>
+    /// Sets the maximum pool size for object reuse
+    /// </summary>
+    public LoggerConfiguration WithPooling(int maxPoolSize = 10000)
+    {
+        Set("MaxPoolSize", maxPoolSize);
+        return this;
+    }
+
+    /// <summary>
+    /// Enables diagnostics collection
+    /// </summary>
+    public LoggerConfiguration WithDiagnostics(bool enabled = true)
+    {
+        Set("DiagnosticsEnabled", enabled);
+        return this;
+    }
+
+    /// <summary>
+    /// Enables context propagation using AsyncLocal
+    /// </summary>
+    public LoggerConfiguration WithContextPropagation(bool enabled = true)
+    {
+        Set("ContextPropagationEnabled", enabled);
+        return this;
+    }
+
+    /// <summary>
+    /// Sets sampling rate (0-1, where 1 = log all events)
+    /// </summary>
+    public LoggerConfiguration WithSampling(double rate)
+    {
+        var clampedRate = rate < 0.0 ? 0.0 : (rate > 1.0 ? 1.0 : rate);
+        Set("SamplingRate", clampedRate);
+        return this;
+    }
+
+    /// <summary>
+    /// Sets rate limit (events per second)
+    /// </summary>
+    public LoggerConfiguration WithRateLimit(int eventsPerSecond)
+    {
+        Set("RateLimit", eventsPerSecond);
+        return this;
+    }
+
+    public Dictionary<string, object> Build()
+    {
+        return new Dictionary<string, object>(_config);
+    }
+}
+
+/// <summary>
+/// Predefined logger presets
+/// </summary>
+public enum LoggerPreset
+{
+    Development,
+    Production,
+    Diagnostics,
+    Performance
+}

EonaCat.LogStack/EonaCatLoggerCore/Destructuring/TypeDestructor.cs

@@ -0,0 +1,368 @@
+using System;
+using System.Collections;
+using System.Collections.Generic;
+using System.Globalization;
+using System.Linq;
+using System.Text;
+
+namespace EonaCat.LogStack.Destructuring;
+
+// This file is part of the EonaCat project(s) which is released under the Apache License.
+// See the LICENSE file or go to https://EonaCat.com/License for full license details.
+
+/// <summary>
+/// Renders complex types to JSON-like format without external dependencies
+/// </summary>
+public sealed class TypeDestructor
+{
+    private readonly HashSet<object> _visited = new();
+    private const int MaxDepth = 10;
+    private const int MaxStringLength = 1000;
+    private const int MaxCollectionItems = 100;
+
+    /// <summary>
+    /// Destructures an object to a string representation (JSON-like format)
+    /// </summary>
+    public string Destructure(object? value)
+    {
+        _visited.Clear();
+        var sb = new StringBuilder();
+        DestructureValue(value, sb, 0);
+        return sb.ToString();
+    }
+
+    private void DestructureValue(object? value, StringBuilder sb, int depth)
+    {
+        if (depth > MaxDepth)
+        {
+            sb.Append("\"...\"");
+            return;
+        }
+
+        if (value == null)
+        {
+            sb.Append("null");
+            return;
+        }
+
+        var type = value.GetType();
+
+        // Handle primitives
+        if (type == typeof(string))
+        {
+            AppendString(sb, (string)value);
+            return;
+        }
+
+        if (type == typeof(bool))
+        {
+            sb.Append(((bool)value) ? "true" : "false");
+            return;
+        }
+
+        if (type == typeof(byte) || type == typeof(sbyte) ||
+            type == typeof(short) || type == typeof(ushort) ||
+            type == typeof(int) || type == typeof(uint) ||
+            type == typeof(long) || type == typeof(ulong))
+        {
+            sb.Append(value);
+            return;
+        }
+
+        if (type == typeof(float) || type == typeof(double) || type == typeof(decimal))
+        {
+            sb.Append(((IFormattable)value).ToString(null, CultureInfo.InvariantCulture));
+            return;
+        }
+
+        if (type == typeof(DateTime))
+        {
+            sb.Append("\"").Append(((DateTime)value).ToIso8601String()).Append("\"");
+            return;
+        }
+
+        if (type == typeof(DateTimeOffset))
+        {
+            sb.Append("\"").Append(((DateTimeOffset)value).ToString("O")).Append("\"");
+            return;
+        }
+
+        if (type == typeof(TimeSpan))
+        {
+            sb.Append("\"").Append(((TimeSpan)value).ToString()).Append("\"");
+            return;
+        }
+
+        if (type == typeof(Guid))
+        {
+            sb.Append("\"").Append(((Guid)value).ToString()).Append("\"");
+            return;
+        }
+
+        // Check for circular references
+        if (_visited.Contains(value))
+        {
+            sb.Append("\"<circular reference>\"");
+            return;
+        }
+
+        _visited.Add(value);
+
+        // Handle collections
+        if (value is IEnumerable enumerable && !(value is string))
+        {
+            DestructureCollection(enumerable, sb, depth);
+            return;
+        }
+
+        // Handle objects
+        DestructureObject(value, sb, depth);
+    }
+
+    private void DestructureCollection(IEnumerable enumerable, StringBuilder sb, int depth)
+    {
+        sb.Append("[");
+        int count = 0;
+
+        foreach (var item in enumerable)
+        {
+            if (count > 0)
+            {
+                sb.Append(",");
+            }
+
+            if (count >= MaxCollectionItems)
+            {
+                sb.Append("\"...\"");
+                break;
+            }
+
+            DestructureValue(item, sb, depth + 1);
+            count++;
+        }
+
+        sb.Append("]");
+    }
+
+    private void DestructureObject(object value, StringBuilder sb, int depth)
+    {
+        sb.Append("{");
+
+        var properties = value.GetType().GetProperties();
+        int count = 0;
+
+        foreach (var prop in properties)
+        {
+            if (count > 0)
+            {
+                sb.Append(",");
+            }
+
+            sb.Append("\"").Append(EscapeJsonString(prop.Name)).Append("\":");
+
+            try
+            {
+                var propValue = prop.GetValue(value);
+                DestructureValue(propValue, sb, depth + 1);
+            }
+            catch
+            {
+                sb.Append("\"<error>\"");
+            }
+
+            count++;
+
+            if (count >= MaxCollectionItems)
+            {
+                sb.Append(",\"...\":null");
+                break;
+            }
+        }
+
+        sb.Append("}");
+    }
+
+    private void AppendString(StringBuilder sb, string value)
+    {
+        sb.Append("\"");
+
+        int length = Math.Min(value.Length, MaxStringLength);
+        for (int i = 0; i < length; i++)
+        {
+            char c = value[i];
+            sb.Append(EscapeChar(c));
+        }
+
+        if (value.Length > MaxStringLength)
+        {
+            sb.Append("...\"");
+        }
+        else
+        {
+            sb.Append("\"");
+        }
+    }
+
+    private static string EscapeJsonString(string value)
+    {
+        var sb = new StringBuilder();
+        foreach (char c in value)
+        {
+            sb.Append(EscapeChar(c));
+        }
+        return sb.ToString();
+    }
+
+    private static string EscapeChar(char c)
+    {
+        return c switch
+        {
+            '"' => "\\\"",
+            '\\' => "\\\\",
+            '\b' => "\\b",
+            '\f' => "\\f",
+            '\n' => "\\n",
+            '\r' => "\\r",
+            '\t' => "\\t",
+            _ => c < 32 ? $"\\u{(int)c:X4}" : c.ToString()
+        };
+    }
+}
+
+/// <summary>
+/// Specialized destructors for common types
+/// </summary>
+public sealed class SpecializedDestructor
+{
+    /// <summary>
+    /// Destructures an exception with full context
+    /// </summary>
+    public static string DestructureException(Exception ex)
+    {
+        var sb = new StringBuilder();
+        sb.Append("{");
+        sb.Append("\"Type\":\"").Append(EscapeJsonString(ex.GetType().Name)).Append("\",");
+        sb.Append("\"Message\":\"").Append(EscapeJsonString(ex.Message)).Append("\",");
+        sb.Append("\"StackTrace\":\"").Append(EscapeJsonString(ex.StackTrace ?? "")).Append("\"");
+
+        if (ex.InnerException != null)
+        {
+            sb.Append(",\"InnerException\":").Append(DestructureException(ex.InnerException));
+        }
+
+        sb.Append("}");
+        return sb.ToString();
+    }
+
+    /// <summary>
+    /// Destructures a key-value pair collection
+    /// </summary>
+    public static string DestructureKeyValuePairs<TKey, TValue>(
+        IEnumerable<KeyValuePair<TKey, TValue>> pairs)
+    {
+        var sb = new StringBuilder();
+        sb.Append("{");
+
+        int count = 0;
+        foreach (var kvp in pairs)
+        {
+            if (count > 0)
+            {
+                sb.Append(",");
+            }
+
+            sb.Append("\"").Append(EscapeJsonString(kvp.Key?.ToString() ?? "null")).Append("\":");
+            sb.Append("\"").Append(EscapeJsonString(kvp.Value?.ToString() ?? "null")).Append("\"");
+
+            count++;
+            if (count >= 100)
+            {
+                break;
+            }
+        }
+
+        sb.Append("}");
+        return sb.ToString();
+    }
+
+    private static string EscapeJsonString(string value)
+    {
+        var sb = new StringBuilder();
+        foreach (char c in value)
+        {
+            sb.Append(c switch
+            {
+                '"' => "\\\"",
+                '\\' => "\\\\",
+                '\b' => "\\b",
+                '\f' => "\\f",
+                '\n' => "\\n",
+                '\r' => "\\r",
+                '\t' => "\\t",
+                _ => c < 32 ? $"\\u{(int)c:X4}" : c.ToString()
+            });
+        }
+        return sb.ToString();
+    }
+}
+
+/// <summary>
+/// Extension methods for type destructuring
+/// </summary>
+public static class DestructuringExtensions
+{
+    /// <summary>
+    /// Converts an object to its destructured JSON representation
+    /// </summary>
+    public static string ToDestructuredJson(this object? value)
+    {
+        if (value == null)
+        {
+            return "null";
+        }
+
+        var destructor = new TypeDestructor();
+        return destructor.Destructure(value);
+    }
+
+    /// <summary>
+    /// Escapes special characters in a string for JSON output
+    /// </summary>
+    public static string ToJsonString(this string value)
+    {
+        if (string.IsNullOrEmpty(value))
+        {
+            return "\"\"";
+        }
+
+        var sb = new StringBuilder();
+        sb.Append("\"");
+        foreach (char c in value)
+        {
+            sb.Append(c switch
+            {
+                '"' => "\\\"",
+                '\\' => "\\\\",
+                '\b' => "\\b",
+                '\f' => "\\f",
+                '\n' => "\\n",
+                '\r' => "\\r",
+                '\t' => "\\t",
+                _ => c < 32 ? $"\\u{(int)c:X4}" : c.ToString()
+            });
+        }
+        sb.Append("\"");
+        return sb.ToString();
+    }
+}
+
+/// <summary>
+/// Extension for ISO 8601 formatting
+/// </summary>
+public static class DateTimeExtensionForDestructuring
+{
+    public static string ToIso8601String(this DateTime dt)
+    {
+        return dt.ToString("yyyy-MM-ddTHH:mm:ss.fffZ");
+    }
+}

EonaCat.LogStack/EonaCatLoggerCore/Diagnostics/LoggerDiagnosticsCollector.cs

@@ -0,0 +1,349 @@
+using EonaCat.LogStack.Core;
+using System;
+using System.Collections.Generic;
+using System.Diagnostics;
+using System.Linq;
+using System.Text;
+
+namespace EonaCat.LogStack.Diagnostics;
+
+// This file is part of the EonaCat project(s) which is released under the Apache License.
+// See the LICENSE file or go to https://EonaCat.com/License for full license details.
+
+/// <summary>
+/// Comprehensive logging diagnostics and metrics collection
+/// </summary>
+public sealed class LoggerDiagnosticsCollector
+{
+    private readonly Stopwatch _uptime = Stopwatch.StartNew();
+    private long _totalEventsProcessed;
+    private long _totalEventsSampled;
+    private long _totalEventsFiltered;
+    private long _totalErrors;
+    private DateTime _startTime = DateTime.UtcNow;
+    private readonly object _lock = new object();
+
+    private readonly Dictionary<string, FlowMetrics> _flowMetrics = new();
+    private readonly Dictionary<string, BoosterMetrics> _boosterMetrics = new();
+    private readonly Dictionary<LogLevel, long> _levelCounts = new();
+    private readonly List<EventLatency> _recentLatencies = new();
+    private const int MaxLatencyHistory = 1000;
+
+    public LoggerDiagnosticsCollector()
+    {
+        foreach (LogLevel level in Enum.GetValues(typeof(LogLevel)))
+        {
+            _levelCounts[level] = 0;
+        }
+    }
+
+    /// <summary>
+    /// Records an event being processed
+    /// </summary>
+    public void RecordEventProcessed(LogEvent logEvent, long elapsedMilliseconds)
+    {
+        lock (_lock)
+        {
+            _totalEventsProcessed++;
+
+            if (_levelCounts.ContainsKey(logEvent.Level))
+            {
+                _levelCounts[logEvent.Level]++;
+            }
+
+            // Track latency
+            _recentLatencies.Add(new EventLatency
+            {
+                Level = logEvent.Level,
+                ElapsedMs = elapsedMilliseconds,
+                Timestamp = DateTime.UtcNow
+            });
+
+            if (_recentLatencies.Count > MaxLatencyHistory)
+            {
+                _recentLatencies.RemoveAt(0);
+            }
+        }
+    }
+
+    /// <summary>
+    /// Records a sampled event
+    /// </summary>
+    public void RecordSampled()
+    {
+        lock (_lock)
+        {
+            _totalEventsSampled++;
+        }
+    }
+
+    /// <summary>
+    /// Records a filtered event
+    /// </summary>
+    public void RecordFiltered()
+    {
+        lock (_lock)
+        {
+            _totalEventsFiltered++;
+        }
+    }
+
+    /// <summary>
+    /// Records an error
+    /// </summary>
+    public void RecordError()
+    {
+        lock (_lock)
+        {
+            _totalErrors++;
+        }
+    }
+
+    /// <summary>
+    /// Records metrics for a flow
+    /// </summary>
+    public void RecordFlowMetrics(string flowName, int eventsProcessed, int eventsFailed, long bytesWritten)
+    {
+        lock (_lock)
+        {
+            if (!_flowMetrics.TryGetValue(flowName, out var metrics))
+            {
+                metrics = new FlowMetrics { Name = flowName };
+                _flowMetrics[flowName] = metrics;
+            }
+
+            metrics.EventsProcessed += eventsProcessed;
+            metrics.EventsFailed += eventsFailed;
+            metrics.BytesWritten += bytesWritten;
+            metrics.LastUpdated = DateTime.UtcNow;
+        }
+    }
+
+    /// <summary>
+    /// Records metrics for a booster
+    /// </summary>
+    public void RecordBoosterMetrics(string boosterName, int eventsProcessed, int eventsFiltered)
+    {
+        lock (_lock)
+        {
+            if (!_boosterMetrics.TryGetValue(boosterName, out var metrics))
+            {
+                metrics = new BoosterMetrics { Name = boosterName };
+                _boosterMetrics[boosterName] = metrics;
+            }
+
+            metrics.EventsProcessed += eventsProcessed;
+            metrics.EventsFiltered += eventsFiltered;
+            metrics.LastUpdated = DateTime.UtcNow;
+        }
+    }
+
+    /// <summary>
+    /// Gets comprehensive diagnostics
+    /// </summary>
+    public DiagnosticsReport GetReport()
+    {
+        lock (_lock)
+        {
+            var latencies = _recentLatencies.Count > 0 ? _recentLatencies.ToList() : new List<EventLatency>();
+
+            return new DiagnosticsReport
+            {
+                StartTime = _startTime,
+                Uptime = _uptime.Elapsed,
+                TotalEventsProcessed = _totalEventsProcessed,
+                TotalEventsSampled = _totalEventsSampled,
+                TotalEventsFiltered = _totalEventsFiltered,
+                TotalErrors = _totalErrors,
+                EventsByLevel = new Dictionary<LogLevel, long>(_levelCounts),
+                FlowMetrics = _flowMetrics.Values.ToList(),
+                BoosterMetrics = _boosterMetrics.Values.ToList(),
+                RecentLatencies = latencies,
+                MemoryUsage = GC.GetTotalMemory(false),
+                ManagedThreadCount = System.Diagnostics.Process.GetCurrentProcess().Threads.Count
+            };
+        }
+    }
+
+    /// <summary>
+    /// Gets a summary report
+    /// </summary>
+    public DiagnosticsSummary GetSummary()
+    {
+        var report = GetReport();
+
+        double successRate = report.TotalEventsProcessed > 0
+            ? ((report.TotalEventsProcessed - report.TotalErrors) * 100.0) / report.TotalEventsProcessed
+            : 0.0;
+
+        double samplingRate = report.TotalEventsProcessed > 0
+            ? (report.TotalEventsSampled * 100.0) / report.TotalEventsProcessed
+            : 0.0;
+
+        var avgLatency = report.RecentLatencies.Count > 0
+            ? report.RecentLatencies.Average(l => l.ElapsedMs)
+            : 0.0;
+
+        var maxLatency = report.RecentLatencies.Count > 0
+            ? report.RecentLatencies.Max(l => l.ElapsedMs)
+            : 0L;
+
+        return new DiagnosticsSummary
+        {
+            Uptime = report.Uptime,
+            TotalEvents = report.TotalEventsProcessed,
+            SuccessRate = successRate,
+            ErrorRate = 100.0 - successRate,
+            SamplingRate = samplingRate,
+            FilteringRate = report.TotalEventsFiltered > 0
+                ? (report.TotalEventsFiltered * 100.0) / report.TotalEventsProcessed
+                : 0.0,
+            EventsPerSecond = report.Uptime.TotalSeconds > 0
+                ? report.TotalEventsProcessed / report.Uptime.TotalSeconds
+                : 0.0,
+            AverageLatencyMs = avgLatency,
+            MaxLatencyMs = maxLatency,
+            MemoryUsageMb = report.MemoryUsage / (1024 * 1024.0),
+            ThreadCount = report.ManagedThreadCount
+        };
+    }
+
+    /// <summary>
+    /// Generates a text report
+    /// </summary>
+    public string GenerateTextReport()
+    {
+        var summary = GetSummary();
+        var report = GetReport();
+
+        var sb = new StringBuilder();
+        sb.AppendLine("╔══════════════════════════════════════════════════════════╗");
+        sb.AppendLine("║         EonaCat.LogStack Diagnostics Report              ║");
+        sb.AppendLine("╚══════════════════════════════════════════════════════════╝");
+        sb.AppendLine();
+
+        sb.AppendLine("📊 Overview");
+        sb.AppendLine($"  Uptime:              {summary.Uptime:hh\\:mm\\:ss}");
+        sb.AppendLine($"  Total Events:        {summary.TotalEvents:N0}");
+        sb.AppendLine($"  Events/Second:       {summary.EventsPerSecond:F2}");
+        sb.AppendLine();
+
+        sb.AppendLine("📈 Quality Metrics");
+        sb.AppendLine($"  Success Rate:        {summary.SuccessRate:F2}%");
+        sb.AppendLine($"  Error Rate:          {summary.ErrorRate:F2}%");
+        sb.AppendLine($"  Sampling Rate:       {summary.SamplingRate:F2}%");
+        sb.AppendLine($"  Filtering Rate:      {summary.FilteringRate:F2}%");
+        sb.AppendLine();
+
+        sb.AppendLine("⚡ Performance");
+        sb.AppendLine($"  Avg Latency:         {summary.AverageLatencyMs:F2}ms");
+        sb.AppendLine($"  Max Latency:         {summary.MaxLatencyMs}ms");
+        sb.AppendLine($"  Memory Usage:        {summary.MemoryUsageMb:F2}MB");
+        sb.AppendLine($"  Threads:             {summary.ThreadCount}");
+        sb.AppendLine();
+
+        sb.AppendLine("📋 Events by Level");
+        foreach (var kvp in report.EventsByLevel.OrderByDescending(x => x.Value))
+        {
+            sb.AppendLine($"  {kvp.Key,-12} {kvp.Value:N0}");
+        }
+        sb.AppendLine();
+
+        if (report.FlowMetrics.Count > 0)
+        {
+            sb.AppendLine("🚀 Flow Metrics");
+            foreach (var flow in report.FlowMetrics)
+            {
+                sb.AppendLine($"  {flow.Name}");
+                sb.AppendLine($"    Processed:  {flow.EventsProcessed:N0}");
+                sb.AppendLine($"    Failed:     {flow.EventsFailed}");
+                sb.AppendLine($"    Bytes:      {flow.BytesWritten:N0}");
+            }
+            sb.AppendLine();
+        }
+
+        if (report.BoosterMetrics.Count > 0)
+        {
+            sb.AppendLine("⚙️  Booster Metrics");
+            foreach (var booster in report.BoosterMetrics)
+            {
+                sb.AppendLine($"  {booster.Name}");
+                sb.AppendLine($"    Processed: {booster.EventsProcessed:N0}");
+                sb.AppendLine($"    Filtered:  {booster.EventsFiltered:N0}");
+            }
+            sb.AppendLine();
+        }
+
+        return sb.ToString();
+    }
+}
+
+/// <summary>
+/// Individual flow metrics
+/// </summary>
+public class FlowMetrics
+{
+    public string Name { get; set; } = "";
+    public long EventsProcessed { get; set; }
+    public long EventsFailed { get; set; }
+    public long BytesWritten { get; set; }
+    public DateTime LastUpdated { get; set; }
+}
+
+/// <summary>
+/// Individual booster metrics
+/// </summary>
+public class BoosterMetrics
+{
+    public string Name { get; set; } = "";
+    public long EventsProcessed { get; set; }
+    public long EventsFiltered { get; set; }
+    public DateTime LastUpdated { get; set; }
+}
+
+/// <summary>
+/// Detailed diagnostics report
+/// </summary>
+public class DiagnosticsReport
+{
+    public DateTime StartTime { get; set; }
+    public TimeSpan Uptime { get; set; }
+    public long TotalEventsProcessed { get; set; }
+    public long TotalEventsSampled { get; set; }
+    public long TotalEventsFiltered { get; set; }
+    public long TotalErrors { get; set; }
+    public Dictionary<LogLevel, long> EventsByLevel { get; set; } = new();
+    public List<FlowMetrics> FlowMetrics { get; set; } = new();
+    public List<BoosterMetrics> BoosterMetrics { get; set; } = new();
+    public List<EventLatency> RecentLatencies { get; set; } = new();
+    public long MemoryUsage { get; set; }
+    public int ManagedThreadCount { get; set; }
+}
+
+/// <summary>
+/// Summary diagnostics
+/// </summary>
+public class DiagnosticsSummary
+{
+    public TimeSpan Uptime { get; set; }
+    public long TotalEvents { get; set; }
+    public double SuccessRate { get; set; }
+    public double ErrorRate { get; set; }
+    public double SamplingRate { get; set; }
+    public double FilteringRate { get; set; }
+    public double EventsPerSecond { get; set; }
+    public double AverageLatencyMs { get; set; }
+    public long MaxLatencyMs { get; set; }
+    public double MemoryUsageMb { get; set; }
+    public int ThreadCount { get; set; }
+}
+
+/// <summary>
+/// Individual event latency record
+/// </summary>
+public class EventLatency
+{
+    public LogLevel Level { get; set; }
+    public long ElapsedMs { get; set; }
+    public DateTime Timestamp { get; set; }
+}

EonaCat.LogStack/EonaCatLoggerCore/DynamicLevelController.cs

@@ -0,0 +1,92 @@
+using EonaCat.LogStack.Core;
+using System;
+using System.Threading;
+
+namespace EonaCat.LogStack.Core;
+
+// This file is part of the EonaCat project(s) which is released under the Apache License.
+// See the LICENSE file or go to https://EonaCat.com/License for full license details.
+
+/// <summary>
+/// Thread-safe runtime log-level controller.
+///
+/// Attach an instance to a logger via <c>logger.UseDynamicLevel(controller)</c>.
+/// The logger will then honour <see cref="CurrentLevel"/> on every log call instead
+/// of the level that was set at build time — allowing level changes without restart.
+///
+/// <example>
+/// <code>
+/// var levelCtrl = new DynamicLevelController(LogLevel.Information);
+/// var logger = new LogBuilder()
+///     .WriteToConsole()
+///     .Build()
+///     .UseDynamicLevel(levelCtrl);
+///
+/// // Later, crank up verbosity for debugging:
+/// levelCtrl.CurrentLevel = LogLevel.Trace;
+///
+/// // Or subscribe to changes:
+/// levelCtrl.LevelChanged += (old, @new) => Console.WriteLine($"Level: {old} → {@new}");
+/// </code>
+/// </example>
+/// </summary>
+public sealed class DynamicLevelController
+{
+    // Store as int for Interlocked operations
+    private int _level;
+
+    /// <summary>Fires whenever the level changes, passing (oldLevel, newLevel).</summary>
+    public event Action<LogLevel, LogLevel>? LevelChanged;
+
+    public DynamicLevelController(LogLevel initialLevel = LogLevel.Information)
+    {
+        _level = (int)initialLevel;
+    }
+
+    /// <summary>Gets or sets the current minimum log level.</summary>
+    public LogLevel CurrentLevel
+    {
+        get => (LogLevel)Volatile.Read(ref _level);
+        set
+        {
+            var old = (LogLevel)Interlocked.Exchange(ref _level, (int)value);
+            if (old != value)
+            {
+                LevelChanged?.Invoke(old, value);
+            }
+        }
+    }
+
+    /// <summary>
+    /// Temporarily raises the level to <paramref name="level"/> and returns a handle
+    /// that restores the previous level when disposed.
+    /// Thread-safe for nested/concurrent usage.
+    /// </summary>
+    public IDisposable TemporaryLevel(LogLevel level)
+    {
+        var previous = CurrentLevel;
+        CurrentLevel = level;
+        return new RestoreHandle(this, previous);
+    }
+
+    private sealed class RestoreHandle : IDisposable
+    {
+        private readonly DynamicLevelController _ctrl;
+        private readonly LogLevel _restore;
+        private int _disposed;
+
+        public RestoreHandle(DynamicLevelController ctrl, LogLevel restore)
+        {
+            _ctrl = ctrl;
+            _restore = restore;
+        }
+
+        public void Dispose()
+        {
+            if (Interlocked.Exchange(ref _disposed, 1) == 0)
+            {
+                _ctrl.CurrentLevel = _restore;
+            }
+        }
+    }
+}

EonaCat.LogStack/EonaCatLoggerCore/Exceptions/AdvancedExceptionRenderer.cs

@@ -0,0 +1,382 @@
+using System;
+using System.Collections.Generic;
+using System.Diagnostics;
+using System.IO;
+using System.Linq;
+using System.Reflection;
+using System.Text;
+using System.Threading;
+
+namespace EonaCat.LogStack.Exceptions;
+
+// This file is part of the EonaCat project(s) which is released under the Apache License.
+// See the LICENSE file or go to https://EonaCat.com/License for full license details.
+
+/// <summary>
+/// Advanced exception rendering with context tracking
+/// </summary>
+public sealed class AdvancedExceptionRenderer
+{
+    private readonly Dictionary<Exception, ExceptionContext> _contextMap = new();
+
+    /// <summary>
+    /// Registers context information for an exception
+    /// </summary>
+    public void RegisterContext(Exception ex, ExceptionContext context)
+    {
+        _contextMap[ex] = context;
+    }
+
+    /// <summary>
+    /// Renders an exception with all available context
+    /// </summary>
+    public string RenderFull(Exception ex)
+    {
+        var sb = new StringBuilder();
+        RenderException(sb, ex, 0, true);
+        return sb.ToString();
+    }
+
+    /// <summary>
+    /// Renders an exception with minimal detail
+    /// </summary>
+    public string RenderShort(Exception ex)
+    {
+        return $"{ex.GetType().Name}: {ex.Message}";
+    }
+
+    /// <summary>
+    /// Renders just the stack trace with source information
+    /// </summary>
+    public string RenderStackTrace(Exception ex)
+    {
+        var sb = new StringBuilder();
+        RenderStackTrace(sb, ex);
+        return sb.ToString();
+    }
+
+    private void RenderException(StringBuilder sb, Exception ex, int depth, bool includeContext)
+    {
+        string indent = new string(' ', depth * 2);
+
+        // Exception header
+        sb.Append(indent).Append(ex.GetType().FullName).Append(": ").Append(ex.Message).AppendLine();
+
+        // Stack trace
+        if (!string.IsNullOrEmpty(ex.StackTrace))
+        {
+            RenderStackTrace(sb, ex);
+        }
+
+        // Context information
+        if (includeContext && _contextMap.TryGetValue(ex, out var context))
+        {
+            sb.Append(indent).Append("Context:").AppendLine();
+            if (context.CorrelationId != null)
+            {
+                sb.Append(indent).Append("  CorrelationId: ").Append(context.CorrelationId).AppendLine();
+            }
+
+            if (context.UserId != null)
+            {
+                sb.Append(indent).Append("  UserId: ").Append(context.UserId).AppendLine();
+            }
+
+            if (context.RequestPath != null)
+            {
+                sb.Append(indent).Append("  RequestPath: ").Append(context.RequestPath).AppendLine();
+            }
+
+            if (context.CustomData != null)
+            {
+                sb.Append(indent).Append("  CustomData:").AppendLine();
+                foreach (var kvp in context.CustomData)
+                {
+                    sb.Append(indent).Append("    ").Append(kvp.Key).Append(": ").Append(kvp.Value).AppendLine();
+                }
+            }
+        }
+
+        // Inner exceptions
+        if (ex.InnerException != null)
+        {
+            sb.Append(indent).Append("InnerException:").AppendLine();
+            RenderException(sb, ex.InnerException, depth + 1, includeContext);
+        }
+    }
+
+    private void RenderStackTrace(StringBuilder sb, Exception ex)
+    {
+        string indent = new string(' ', 4);
+        var frames = new StackTrace(ex, true).GetFrames() ?? Array.Empty<StackFrame>();
+
+        foreach (var frame in frames)
+        {
+            var method = frame.GetMethod();
+            if (method == null)
+            {
+                continue;
+            }
+
+            sb.Append(indent).Append("at ");
+
+            // Type and method
+            if (method.DeclaringType != null)
+            {
+                sb.Append(method.DeclaringType.Name).Append(".");
+            }
+            sb.Append(method.Name);
+
+            // Parameters
+            var parameters = method.GetParameters();
+            if (parameters.Length > 0)
+            {
+                sb.Append("(");
+                for (int i = 0; i < parameters.Length; i++)
+                {
+                    if (i > 0)
+                    {
+                        sb.Append(", ");
+                    }
+
+                    sb.Append(parameters[i].ParameterType.Name);
+                }
+                sb.Append(")");
+            }
+            else
+            {
+                sb.Append("()");
+            }
+
+            // File and line number
+            string fileName = frame.GetFileName();
+            if (!string.IsNullOrEmpty(fileName))
+            {
+                int lineNumber = frame.GetFileLineNumber();
+                sb.Append(" in ").Append(Path.GetFileName(fileName)).Append(":line ").Append(lineNumber);
+            }
+
+            sb.AppendLine();
+        }
+    }
+}
+
+/// <summary>
+/// Context information associated with an exception
+/// </summary>
+public sealed class ExceptionContext
+{
+    public string? CorrelationId { get; set; }
+    public string? UserId { get; set; }
+    public string? RequestPath { get; set; }
+    public Dictionary<string, object?>? CustomData { get; set; }
+    public DateTime OccurredAt { get; set; }
+
+    public ExceptionContext()
+    {
+        OccurredAt = DateTime.UtcNow;
+        CustomData = new Dictionary<string, object?>();
+    }
+
+    /// <summary>
+    /// Builder pattern for fluent context creation
+    /// </summary>
+    public static ExceptionContextBuilder Create()
+    {
+        return new ExceptionContextBuilder();
+    }
+}
+
+/// <summary>
+/// Builder for exception context
+/// </summary>
+public sealed class ExceptionContextBuilder
+{
+    private readonly ExceptionContext _context = new();
+
+    public ExceptionContextBuilder WithCorrelationId(string id)
+    {
+        _context.CorrelationId = id;
+        return this;
+    }
+
+    public ExceptionContextBuilder WithUserId(string userId)
+    {
+        _context.UserId = userId;
+        return this;
+    }
+
+    public ExceptionContextBuilder WithRequestPath(string path)
+    {
+        _context.RequestPath = path;
+        return this;
+    }
+
+    public ExceptionContextBuilder WithCustomData(string key, object? value)
+    {
+        _context.CustomData![key] = value;
+        return this;
+    }
+
+    public ExceptionContextBuilder WithCustomData(Dictionary<string, object?> data)
+    {
+        if (data != null)
+        {
+            foreach (var kvp in data)
+            {
+                _context.CustomData![kvp.Key] = kvp.Value;
+            }
+        }
+        return this;
+    }
+
+    public ExceptionContext Build()
+    {
+        return _context;
+    }
+}
+
+/// <summary>
+/// Global exception context manager
+/// </summary>
+public static class ExceptionContextManager
+{
+    private static readonly object _lock = new object();
+    private static readonly Dictionary<Exception, ExceptionContext> _contextMap = new();
+
+    /// <summary>
+    /// Gets or creates context for an exception
+    /// </summary>
+    public static ExceptionContext GetOrCreateContext(Exception ex)
+    {
+        lock (_lock)
+        {
+            if (!_contextMap.TryGetValue(ex, out var context))
+            {
+                context = new ExceptionContext();
+                _contextMap[ex] = context;
+            }
+            return context;
+        }
+    }
+
+    /// <summary>
+    /// Enriches an exception with context
+    /// </summary>
+    public static Exception WithContext(this Exception ex, Action<ExceptionContextBuilder> configure)
+    {
+        var builder = ExceptionContext.Create();
+        configure(builder);
+        lock (_lock)
+        {
+            _contextMap[ex] = builder.Build();
+        }
+        return ex;
+    }
+
+    /// <summary>
+    /// Gets context for an exception, or null if none exists
+    /// </summary>
+    public static ExceptionContext? TryGetContext(Exception ex)
+    {
+        lock (_lock)
+        {
+            _contextMap.TryGetValue(ex, out var context);
+            return context;
+        }
+    }
+
+    /// <summary>
+    /// Clears all stored contexts
+    /// </summary>
+    public static void Clear()
+    {
+        lock (_lock)
+        {
+            _contextMap.Clear();
+        }
+    }
+}
+
+/// <summary>
+/// Exception aggregator for batch exception handling
+/// </summary>
+public sealed class ExceptionAggregator
+{
+    private readonly List<Exception> _exceptions = new();
+    private readonly string _message;
+
+    public ExceptionAggregator(string message = "One or more exceptions occurred")
+    {
+        _message = message;
+    }
+
+    public void Add(Exception ex)
+    {
+        if (ex != null)
+        {
+            _exceptions.Add(ex);
+        }
+    }
+
+    public void Add(IEnumerable<Exception> exceptions)
+    {
+        if (exceptions != null)
+        {
+            _exceptions.AddRange(exceptions.Where(e => e != null));
+        }
+    }
+
+    public bool HasExceptions => _exceptions.Count > 0;
+
+    public int Count => _exceptions.Count;
+
+    public void ThrowIfHasExceptions()
+    {
+        if (_exceptions.Count == 0)
+        {
+            return;
+        }
+
+        if (_exceptions.Count == 1)
+        {
+            throw _exceptions[0];
+        }
+
+        throw new AggregateException(_message, _exceptions);
+    }
+
+    public IReadOnlyList<Exception> GetExceptions()
+    {
+        return _exceptions.AsReadOnly();
+    }
+
+    public string GetSummary()
+    {
+        if (_exceptions.Count == 0)
+        {
+            return "No exceptions";
+        }
+
+        var sb = new StringBuilder();
+        sb.Append(_message).Append(" (").Append(_exceptions.Count).AppendLine("):");
+
+        for (int i = 0; i < _exceptions.Count && i < 10; i++)
+        {
+            var ex = _exceptions[i];
+            sb.Append($"  [{i + 1}] {ex.GetType().Name}: {ex.Message}").AppendLine();
+        }
+
+        if (_exceptions.Count > 10)
+        {
+            sb.Append($"  ... and {_exceptions.Count - 10} more").AppendLine();
+        }
+
+        return sb.ToString();
+    }
+
+    public void Clear()
+    {
+        _exceptions.Clear();
+    }
+}

EonaCat.LogStack/EonaCatLoggerCore/Filtering/AdvancedFilter.cs

@@ -0,0 +1,397 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using EonaCat.LogStack.Core;
+
+namespace EonaCat.LogStack.Filtering;
+
+// This file is part of the EonaCat project(s) which is released under the Apache License.
+// See the LICENSE file or go to https://EonaCat.com/License for full license details.
+
+/// <summary>
+/// Advanced filtering conditions beyond simple log levels
+/// </summary>
+public abstract class FilterCondition
+{
+    public abstract bool Matches(LogEvent logEvent, Dictionary<string, object?> properties);
+}
+
+/// <summary>
+/// Filters on log level
+/// </summary>
+public sealed class LogLevelFilter : FilterCondition
+{
+    private readonly LogLevel _minLevel;
+    private readonly LogLevel _maxLevel;
+
+    public LogLevelFilter(LogLevel minLevel, LogLevel maxLevel = LogLevel.Critical)
+    {
+        _minLevel = minLevel;
+        _maxLevel = maxLevel;
+    }
+
+    public override bool Matches(LogEvent logEvent, Dictionary<string, object?> properties)
+    {
+        return logEvent.Level >= _minLevel && logEvent.Level <= _maxLevel;
+    }
+}
+
+/// <summary>
+/// Filters based on logger name pattern (supports wildcards)
+/// </summary>
+public sealed class LoggerNameFilter : FilterCondition
+{
+    private readonly string _pattern;
+    private readonly bool _negate;
+
+    public LoggerNameFilter(string pattern, bool negate = false)
+    {
+        _pattern = pattern ?? "";
+        _negate = negate;
+    }
+
+    public override bool Matches(LogEvent logEvent, Dictionary<string, object?> properties)
+    {
+        // Logger name checking would be done here when LogEvent has LoggerName property available
+        // For now, return based on negate flag
+        return _negate;
+    }
+
+    private bool WildcardMatch(string text, string pattern)
+    {
+        if (pattern == "*")
+        {
+            return true;
+        }
+
+        int textIndex = 0;
+        int patternIndex = 0;
+
+        while (textIndex < text.Length && patternIndex < pattern.Length)
+        {
+            if (pattern[patternIndex] == '*')
+            {
+                if (patternIndex + 1 >= pattern.Length)
+                {
+                    return true;
+                }
+
+                var nextChar = pattern[patternIndex + 1];
+                while (textIndex < text.Length && text[textIndex] != nextChar)
+                {
+                    textIndex++;
+                }
+
+                if (textIndex >= text.Length)
+                {
+                    return false;
+                }
+
+                patternIndex++;
+            }
+            else if (pattern[patternIndex] == '?')
+            {
+                textIndex++;
+                patternIndex++;
+            }
+            else if (pattern[patternIndex] == text[textIndex])
+            {
+                textIndex++;
+                patternIndex++;
+            }
+            else
+            {
+                return false;
+            }
+        }
+
+        while (patternIndex < pattern.Length && pattern[patternIndex] == '*')
+        {
+            patternIndex++;
+        }
+
+        return textIndex == text.Length && patternIndex == pattern.Length;
+    }
+}
+
+/// <summary>
+/// Filters on message content
+/// </summary>
+public sealed class MessageFilter : FilterCondition
+{
+    private readonly string _contains;
+    private readonly bool _caseSensitive;
+    private readonly bool _negate;
+
+    public MessageFilter(string contains, bool caseSensitive = false, bool negate = false)
+    {
+        _contains = contains ?? "";
+        _caseSensitive = caseSensitive;
+        _negate = negate;
+    }
+
+    public override bool Matches(LogEvent logEvent, Dictionary<string, object?> properties)
+    {
+        string message = "";
+        var comparison = _caseSensitive ? StringComparison.Ordinal : StringComparison.OrdinalIgnoreCase;
+        bool matches = message.Contains(_contains, comparison);
+        return _negate ? !matches : matches;
+    }
+}
+
+/// <summary>
+/// Filters on exception type
+/// </summary>
+public sealed class ExceptionTypeFilter : FilterCondition
+{
+    private readonly Type _exceptionType;
+    private readonly bool _includeInherited;
+    private readonly bool _negate;
+
+    public ExceptionTypeFilter(Type exceptionType, bool includeInherited = true, bool negate = false)
+    {
+        _exceptionType = exceptionType;
+        _includeInherited = includeInherited;
+        _negate = negate;
+    }
+
+    public override bool Matches(LogEvent logEvent, Dictionary<string, object?> properties)
+    {
+        // Exception checking would be done here when LogEvent has Exception property available
+        // For now, return based on negate flag
+        return _negate;
+    }
+}
+
+/// <summary>
+/// Filters on property values
+/// </summary>
+public sealed class PropertyFilter : FilterCondition
+{
+    private readonly string _propertyName;
+    private readonly Func<object?, bool> _predicate;
+
+    public PropertyFilter(string propertyName, Func<object?, bool> predicate)
+    {
+        _propertyName = propertyName;
+        _predicate = predicate;
+    }
+
+    public override bool Matches(LogEvent logEvent, Dictionary<string, object?> properties)
+    {
+        if (!properties.TryGetValue(_propertyName, out var value))
+        {
+            return false;
+        }
+
+        try
+        {
+            return _predicate(value);
+        }
+        catch
+        {
+            return false;
+        }
+    }
+}
+
+/// <summary>
+/// Composite filter with AND logic
+/// </summary>
+public sealed class AndFilter : FilterCondition
+{
+    private readonly List<FilterCondition> _conditions;
+
+    public AndFilter(params FilterCondition[] conditions)
+    {
+        _conditions = new List<FilterCondition>(conditions);
+    }
+
+    public override bool Matches(LogEvent logEvent, Dictionary<string, object?> properties)
+    {
+        return _conditions.All(c => c.Matches(logEvent, properties));
+    }
+}
+
+/// <summary>
+/// Composite filter with OR logic
+/// </summary>
+public sealed class OrFilter : FilterCondition
+{
+    private readonly List<FilterCondition> _conditions;
+
+    public OrFilter(params FilterCondition[] conditions)
+    {
+        _conditions = new List<FilterCondition>(conditions);
+    }
+
+    public override bool Matches(LogEvent logEvent, Dictionary<string, object?> properties)
+    {
+        return _conditions.Any(c => c.Matches(logEvent, properties));
+    }
+}
+
+/// <summary>
+/// Composite filter with NOT logic
+/// </summary>
+public sealed class NotFilter : FilterCondition
+{
+    private readonly FilterCondition _condition;
+
+    public NotFilter(FilterCondition condition)
+    {
+        _condition = condition;
+    }
+
+    public override bool Matches(LogEvent logEvent, Dictionary<string, object?> properties)
+    {
+        return !_condition.Matches(logEvent, properties);
+    }
+}
+
+/// <summary>
+/// Fluent filter builder
+/// </summary>
+public sealed class FilterBuilder
+{
+    private FilterCondition? _condition;
+
+    public FilterBuilder MinLevel(string levelName)
+    {
+        // When level enum is available in scope, use it here
+        return this;
+    }
+
+    public FilterBuilder MaxLevel(string levelName)
+    {
+        // When level enum is available in scope, use it here
+        return this;
+    }
+
+    public FilterBuilder Level(string min, string max)
+    {
+        // When level enum is available in scope, use it here
+        return this;
+    }
+
+    public FilterBuilder LoggerName(string pattern)
+    {
+        _condition = And(_condition, new LoggerNameFilter(pattern));
+        return this;
+    }
+
+    public FilterBuilder NotLoggerName(string pattern)
+    {
+        _condition = And(_condition, new LoggerNameFilter(pattern, true));
+        return this;
+    }
+
+    public FilterBuilder MessageContains(string text, bool caseSensitive = false)
+    {
+        _condition = And(_condition, new MessageFilter(text, caseSensitive));
+        return this;
+    }
+
+    public FilterBuilder MessageNotContains(string text, bool caseSensitive = false)
+    {
+        _condition = And(_condition, new MessageFilter(text, caseSensitive, true));
+        return this;
+    }
+
+    public FilterBuilder ExceptionType(Type exceptionType, bool includeInherited = true)
+    {
+        _condition = And(_condition, new ExceptionTypeFilter(exceptionType, includeInherited));
+        return this;
+    }
+
+    public FilterBuilder ExceptionType<TException>(bool includeInherited = true) where TException : Exception
+    {
+        _condition = And(_condition, new ExceptionTypeFilter(typeof(TException), includeInherited));
+        return this;
+    }
+
+    public FilterBuilder Property(string propertyName, Func<object?, bool> predicate)
+    {
+        _condition = And(_condition, new PropertyFilter(propertyName, predicate));
+        return this;
+    }
+
+    public FilterBuilder Property(string propertyName, object value)
+    {
+        _condition = And(_condition, new PropertyFilter(propertyName, v => Equals(v, value)));
+        return this;
+    }
+
+    public FilterBuilder Or(FilterBuilder other)
+    {
+        if (_condition == null || other._condition == null)
+        {
+            return this;
+        }
+
+        _condition = new OrFilter(_condition, other._condition);
+        return this;
+    }
+
+    public FilterCondition? Build()
+    {
+        return _condition;
+    }
+
+    private static FilterCondition And(FilterCondition? left, FilterCondition right)
+    {
+        return left == null ? right : new AndFilter(left, right);
+    }
+}
+
+/// <summary>
+/// Manager for applying filters to events
+/// </summary>
+public sealed class FilterManager
+{
+    private readonly List<(string name, FilterCondition condition, FilterAction action)> _filters = new();
+
+    /// <summary>
+    /// Registers a filter with an action
+    /// </summary>
+    public FilterManager Register(string name, FilterCondition condition, FilterAction action)
+    {
+        _filters.Add((name, condition, action));
+        return this;
+    }
+
+    /// <summary>
+    /// Evaluates all registered filters
+    /// </summary>
+    public FilterAction Evaluate(LogEvent logEvent, Dictionary<string, object?> properties)
+    {
+        foreach (var (name, condition, action) in _filters)
+        {
+            if (condition.Matches(logEvent, properties))
+            {
+                return action;
+            }
+        }
+
+        return FilterAction.Continue;
+    }
+
+    public int Count => _filters.Count;
+
+    public void Clear()
+    {
+        _filters.Clear();
+    }
+}
+
+/// <summary>
+/// Filter actions
+/// </summary>
+public enum FilterAction
+{
+    Continue,    // Process normally
+    Ignore,      // Skip this event
+    Critical,    // Mark as critical
+    Suppress,    // Don't log to standard output, only to filters
+}

EonaCat.LogStack/EonaCatLoggerCore/Flows/CircuitBreakerFlow.cs

@@ -0,0 +1,179 @@
+using EonaCat.LogStack.Core;
+using System;
+using System.Diagnostics;
+using System.Runtime.CompilerServices;
+using System.Threading;
+using System.Threading.Tasks;
+
+namespace EonaCat.LogStack.Flows;
+
+// This file is part of the EonaCat project(s) which is released under the Apache License.
+// See the LICENSE file or go to https://EonaCat.com/License for full license details.
+
+/// <summary>
+/// Circuit-breaker state machine.
+/// </summary>
+public enum CircuitState
+{
+    /// <summary>Flow is healthy; all events are forwarded.</summary>
+    Closed,
+    /// <summary>Too many failures; events are dropped to protect the inner flow.</summary>
+    Open,
+    /// <summary>Recovery probe in progress; one event is let through per interval.</summary>
+    HalfOpen
+}
+
+/// <summary>
+/// A decorator flow that implements the Circuit Breaker pattern around any inner flow.
+///
+/// Transitions:
+///   Closed  → Open     : after <see cref="FailureThreshold"/> consecutive failures
+///   Open    → HalfOpen : after <see cref="RecoveryTimeout"/> has elapsed
+///   HalfOpen→ Closed   : on a successful probe write
+///   HalfOpen→ Open     : on a failed probe write
+///
+/// When Open, <see cref="BlastAsync"/> returns <see cref="WriteResult.Dropped"/> immediately
+/// without touching the inner flow — preventing cascades into broken endpoints.
+///
+/// The <see cref="StateChanged"/> event fires on every state transition.
+/// </summary>
+public sealed class CircuitBreakerFlow : FlowBase
+{
+    private readonly IFlow _inner;
+    private readonly int _failureThreshold;
+    private readonly TimeSpan _recoveryTimeout;
+
+    private volatile int _consecutiveFailures;
+    private volatile CircuitState _state = CircuitState.Closed;
+
+    // Stopwatch restarted every time we enter Open state
+    private readonly Stopwatch _openedAt = new Stopwatch();
+
+    private readonly object _stateLock = new object();
+
+    /// <summary>Fires whenever the circuit state changes (from, to).</summary>
+    public event Action<CircuitState, CircuitState> StateChanged;
+
+    public CircuitBreakerFlow(
+        IFlow inner,
+        int failureThreshold = 5,
+        TimeSpan? recoveryTimeout = null,
+        LogLevel minimumLevel = LogLevel.Trace)
+        : base($"CircuitBreaker({(inner != null ? inner.Name : "?")})", minimumLevel)
+    {
+        _inner = inner ?? throw new ArgumentNullException(nameof(inner));
+        _failureThreshold = failureThreshold > 0 ? failureThreshold : 5;
+        _recoveryTimeout = recoveryTimeout ?? TimeSpan.FromSeconds(30);
+    }
+
+    /// <summary>Current state of the circuit breaker.</summary>
+    public CircuitState State => _state;
+
+    /// <summary>Number of consecutive failures since the last successful write.</summary>
+    public int ConsecutiveFailures => _consecutiveFailures;
+
+    [MethodImpl(MethodImplOptions.AggressiveInlining)]
+    public override async Task<WriteResult> BlastAsync(LogEvent logEvent, CancellationToken cancellationToken = default)
+    {
+        if (!IsEnabled || !IsLogLevelEnabled(logEvent))
+        {
+            return WriteResult.LevelFiltered;
+        }
+
+        var currentState = GetEffectiveState();
+
+        if (currentState == CircuitState.Open)
+        {
+            Interlocked.Increment(ref DroppedCount);
+            return WriteResult.Dropped;
+        }
+
+        WriteResult result;
+        try
+        {
+            result = await _inner.BlastAsync(logEvent, cancellationToken).ConfigureAwait(false);
+        }
+        catch (Exception)
+        {
+            result = WriteResult.Failed;
+        }
+
+        if (result == WriteResult.Success)
+        {
+            OnSuccess(currentState);
+            Interlocked.Increment(ref BlastedCount);
+        }
+        else
+        {
+            OnFailure();
+            Interlocked.Increment(ref DroppedCount);
+        }
+
+        return result;
+    }
+
+    public override Task FlushAsync(CancellationToken cancellationToken = default)
+        => _inner.FlushAsync(cancellationToken);
+
+    public override ValueTask DisposeAsync() => _inner.DisposeAsync();
+
+    private CircuitState GetEffectiveState()
+    {
+        if (_state != CircuitState.Open)
+        {
+            return _state;
+        }
+
+        if (_openedAt.Elapsed >= _recoveryTimeout)
+        {
+            Transition(CircuitState.Open, CircuitState.HalfOpen);
+            return CircuitState.HalfOpen;
+        }
+
+        return CircuitState.Open;
+    }
+
+    private void OnSuccess(CircuitState wasState)
+    {
+        Interlocked.Exchange(ref _consecutiveFailures, 0);
+        if (wasState == CircuitState.HalfOpen)
+        {
+            Transition(CircuitState.HalfOpen, CircuitState.Closed);
+        }
+    }
+
+    private void OnFailure()
+    {
+        var failures = Interlocked.Increment(ref _consecutiveFailures);
+        if (_state == CircuitState.HalfOpen)
+        {
+            Transition(CircuitState.HalfOpen, CircuitState.Open);
+        }
+        else if (_state == CircuitState.Closed && failures >= _failureThreshold)
+        {
+            Transition(CircuitState.Closed, CircuitState.Open);
+        }
+    }
+
+    private void Transition(CircuitState from, CircuitState to)
+    {
+        lock (_stateLock)
+        {
+            if (_state != from)
+            {
+                return;
+            }
+
+            _state = to;
+            if (to == CircuitState.Open)
+            {
+                _openedAt.Restart();
+            }
+            else if (to == CircuitState.Closed)
+            {
+                _openedAt.Reset();
+            }
+        }
+        StateChanged?.Invoke(from, to);
+    }
+}

EonaCat.LogStack/EonaCatLoggerCore/Flows/ConditionalFlow.cs

@@ -0,0 +1,103 @@
+using EonaCat.LogStack.Core;
+using System;
+using System.Runtime.CompilerServices;
+using System.Threading;
+using System.Threading.Tasks;
+
+namespace EonaCat.LogStack.Flows;
+
+// This file is part of the EonaCat project(s) which is released under the Apache License.
+// See the LICENSE file or go to https://EonaCat.com/License for full license details.
+
+/// <summary>
+/// A decorator flow that forwards events to an inner flow only when a user-supplied
+/// predicate returns <c>true</c>.
+///
+/// Common use-cases:
+///   • Category-based routing  — route only "Database" category events to file
+///   • Level-range filtering   — forward Warning≤level&lt;Error to one flow
+///   • Property filtering      — only forward events that carry a specific property
+///   • Exception routing       — send events with SqlException to a special alert flow
+///
+/// <example>
+/// <code>
+/// // Route only Database category errors to a dedicated file
+/// new LogBuilder()
+///     .WriteToConditional(
+///         predicate: e => e.Category == "Database" &amp;&amp; e.Level >= LogLevel.Error,
+///         inner: new FileFlow("logs/db-errors"))
+/// </code>
+/// </example>
+/// </summary>
+public sealed class ConditionalFlow : FlowBase
+{
+    private readonly IFlow _inner;
+    private readonly Func<LogEvent, bool> _predicate;
+
+    public ConditionalFlow(
+        IFlow inner,
+        Func<LogEvent, bool> predicate,
+        LogLevel minimumLevel = LogLevel.Trace)
+        : base($"Conditional({inner?.Name ?? "?"})", minimumLevel)
+    {
+        _inner     = inner     ?? throw new ArgumentNullException(nameof(inner));
+        _predicate = predicate ?? throw new ArgumentNullException(nameof(predicate));
+    }
+
+    [MethodImpl(MethodImplOptions.AggressiveInlining)]
+    public override async Task<WriteResult> BlastAsync(LogEvent logEvent, CancellationToken cancellationToken = default)
+    {
+        if (!IsEnabled || !IsLogLevelEnabled(logEvent))
+        {
+            return WriteResult.LevelFiltered;
+        }
+
+        bool matches;
+        try { matches = _predicate(logEvent); }
+        catch { matches = false; }
+
+        if (!matches)
+        {
+            Interlocked.Increment(ref DroppedCount);
+            return WriteResult.Dropped;
+        }
+
+        var result = await _inner.BlastAsync(logEvent, cancellationToken).ConfigureAwait(false);
+        Interlocked.Increment(ref BlastedCount);
+        return result;
+    }
+
+    public override async Task<WriteResult> BlastBatchAsync(
+        ReadOnlyMemory<LogEvent> logEvents, CancellationToken cancellationToken = default)
+    {
+        if (!IsEnabled)
+        {
+            return WriteResult.FlowDisabled;
+        }
+
+        var result = WriteResult.Success;
+        var eventsArray = logEvents.ToArray();
+        foreach (var ev in eventsArray)
+        {
+            bool matches;
+            try { matches = ev.Level >= MinimumLevel && _predicate(ev); }
+            catch { matches = false; }
+
+            if (!matches) { Interlocked.Increment(ref DroppedCount); continue; }
+
+            var r = await _inner.BlastAsync(ev, cancellationToken).ConfigureAwait(false);
+            Interlocked.Increment(ref BlastedCount);
+            if (r != WriteResult.Success)
+            {
+                result = r;
+            }
+        }
+
+        return result;
+    }
+
+    public override Task FlushAsync(CancellationToken cancellationToken = default)
+        => _inner.FlushAsync(cancellationToken);
+
+    public override ValueTask DisposeAsync() => _inner.DisposeAsync();
+}

EonaCat.LogStack/EonaCatLoggerCore/Flows/LokiFlow.cs

@@ -0,0 +1,308 @@
+using EonaCat.LogStack.Core;
+using System;
+using System.Collections.Concurrent;
+using System.Collections.Generic;
+using System.Linq;
+using System.Net.Http;
+using System.Net.Http.Headers;
+using System.Runtime.CompilerServices;
+using System.Text;
+using EonaCat.Json;
+using System.Threading;
+using System.Threading.Tasks;
+
+namespace EonaCat.LogStack.Flows;
+
+// This file is part of the EonaCat project(s) which is released under the Apache License.
+// See the LICENSE file or go to https://EonaCat.com/License for full license details.
+
+/// <summary>
+/// Pushes log events to a Grafana Loki instance via the HTTP log-push API
+/// (<c>POST /loki/api/v1/push</c>).
+///
+/// Features:
+///   • Batching by count and/or flush interval
+///   • Configurable static labels (stream selectors)
+///   • Auto-label from event Level and Category
+///   • Optional HTTP Basic / Bearer authentication
+///   • Structured JSON line bodies (all properties serialised)
+///   • Compatible with Loki 2.x and 3.x
+///
+/// <example>
+/// <code>
+/// new LogBuilder()
+///     .WriteToLoki(
+///         lokiUrl: "http://loki:3100",
+///         labels: new() { ["app"] = "myapp", ["env"] = "prod" },
+///         batchSize: 100,
+///         batchIntervalMs: 2000)
+/// </code>
+/// </example>
+/// </summary>
+public sealed class LokiFlow : FlowBase
+{
+    private const string PushPath = "/loki/api/v1/push";
+
+    private readonly HttpClient _http;
+    private readonly bool _ownsHttpClient;
+    private readonly string _lokiPushUrl;
+    private readonly Dictionary<string, string> _staticLabels;
+    private readonly int _batchSize;
+    private readonly TimeSpan _batchInterval;
+    private readonly ConcurrentQueue<(string Labels, string Line, long NanoTs)> _queue = new();
+    private readonly CancellationTokenSource _cts = new();
+    private readonly Task _flushTask;
+    private readonly SemaphoreSlim _batchSignal = new(0, int.MaxValue);
+
+    public LokiFlow(
+        string lokiUrl,
+        Dictionary<string, string>? labels = null,
+        int batchSize = 50,
+        int batchIntervalMs = 1000,
+        string? bearerToken = null,
+        string? basicUser = null,
+        string? basicPassword = null,
+        HttpClient? httpClient = null,
+        LogLevel minimumLevel = LogLevel.Trace)
+        : base("Loki", minimumLevel)
+    {
+        if (string.IsNullOrWhiteSpace(lokiUrl))
+        {
+            throw new ArgumentNullException(nameof(lokiUrl));
+        }
+
+        _lokiPushUrl = lokiUrl.TrimEnd('/') + PushPath;
+        _staticLabels = labels ?? new Dictionary<string, string>();
+        _batchSize = batchSize > 0 ? batchSize : 50;
+        _batchInterval = TimeSpan.FromMilliseconds(batchIntervalMs > 0 ? batchIntervalMs : 1000);
+
+        if (httpClient != null)
+        {
+            _http = httpClient;
+            _ownsHttpClient = false;
+        }
+        else
+        {
+            _http = new HttpClient { Timeout = TimeSpan.FromSeconds(15) };
+            _ownsHttpClient = true;
+        }
+
+        if (!string.IsNullOrEmpty(bearerToken))
+        {
+            _http.DefaultRequestHeaders.Authorization = new AuthenticationHeaderValue("Bearer", bearerToken);
+        }
+        else if (!string.IsNullOrEmpty(basicUser))
+        {
+            var encoded = Convert.ToBase64String(Encoding.UTF8.GetBytes($"{basicUser}:{basicPassword}"));
+            _http.DefaultRequestHeaders.Authorization = new AuthenticationHeaderValue("Basic", encoded);
+        }
+
+        _flushTask = Task.Run(() => BackgroundFlushAsync(_cts.Token));
+    }
+
+    [MethodImpl(MethodImplOptions.AggressiveInlining)]
+    public override Task<WriteResult> BlastAsync(LogEvent logEvent, CancellationToken cancellationToken = default)
+    {
+        if (!IsEnabled || !IsLogLevelEnabled(logEvent))
+        {
+            return Task.FromResult(WriteResult.LevelFiltered);
+        }
+
+        var labels  = BuildLabels(logEvent);
+        var line    = BuildLine(logEvent);
+        var nanoTs  = logEvent.Timestamp * 100L; // ticks → nanoseconds
+
+        _queue.Enqueue((labels, line, nanoTs));
+        Interlocked.Increment(ref BlastedCount);
+
+        if (_queue.Count >= _batchSize)
+        {
+            _batchSignal.Release(1);
+        }
+
+        return Task.FromResult(WriteResult.Success);
+    }
+
+    public override async Task FlushAsync(CancellationToken cancellationToken = default)
+    {
+        await SendBatchAsync(cancellationToken).ConfigureAwait(false);
+    }
+
+    public override async ValueTask DisposeAsync()
+    {
+        IsEnabled = false;
+        _cts.Cancel();
+        try { await _flushTask.ConfigureAwait(false); } catch { }
+        await SendBatchAsync(default).ConfigureAwait(false);
+        if (_ownsHttpClient)
+        {
+            _http.Dispose();
+        }
+
+        _cts.Dispose();
+        GC.SuppressFinalize(this);
+    }
+
+    // Background flush loop
+    private async Task BackgroundFlushAsync(CancellationToken ct)
+    {
+        while (!ct.IsCancellationRequested)
+        {
+            try
+            {
+                await _batchSignal.WaitAsync(_batchInterval, ct).ConfigureAwait(false);
+                await SendBatchAsync(ct).ConfigureAwait(false);
+            }
+            catch (OperationCanceledException) { break; }
+            catch { }
+        }
+        await SendBatchAsync(default).ConfigureAwait(false);
+    }
+
+    private async Task SendBatchAsync(CancellationToken ct)
+    {
+        if (_queue.IsEmpty)
+        {
+            return;
+        }
+
+        // Group by label-set (Loki stream key)
+        var groups = new Dictionary<string, List<(string Line, long NanoTs)>>(StringComparer.Ordinal);
+        while (_queue.TryDequeue(out var item))
+        {
+            if (!groups.TryGetValue(item.Labels, out var list))
+            {
+                list = new List<(string, long)>(16);
+                groups[item.Labels] = list;
+            }
+            list.Add((item.Line, item.NanoTs));
+        }
+
+        if (groups.Count == 0)
+        {
+            return;
+        }
+
+        var body = BuildPushJson(groups);
+        try
+        {
+            var content = new StringContent(body, Encoding.UTF8, "application/json");
+            using var response = await _http.PostAsync(_lokiPushUrl, content, ct).ConfigureAwait(false);
+            if (!response.IsSuccessStatusCode)
+            {
+                Interlocked.Add(ref DroppedCount, SumGroups(groups));
+            }
+        }
+        catch
+        {
+            Interlocked.Add(ref DroppedCount, SumGroups(groups));
+        }
+    }
+
+    private string BuildLabels(LogEvent e)
+    {
+        var sb = new StringBuilder("{");
+        bool first = true;
+
+        foreach (var kv in _staticLabels)
+        {
+            if (!first)
+            {
+                sb.Append(", ");
+            }
+
+            sb.Append('"').Append(kv.Key).Append("\": \"").Append(kv.Value).Append('"');
+            first = false;
+        }
+
+        // Auto-labels
+        AppendLabel(sb, "level",    e.Level.ToString(), ref first);
+        if (e.HasCategory)
+        {
+            AppendLabel(sb, "category", e.Category,        ref first);
+        }
+
+        sb.Append('}');
+        return sb.ToString();
+    }
+
+    private static void AppendLabel(StringBuilder sb, string key, string value, ref bool first)
+    {
+        if (!first)
+        {
+            sb.Append(", ");
+        }
+
+        sb.Append('"').Append(key).Append("\": \"").Append(EscapeJson(value)).Append('"');
+        first = false;
+    }
+
+    private string BuildLine(LogEvent e)
+    {
+        using var doc = new Utf8JsonWriter_Builder();
+        var obj = new
+        {
+            level     = e.Level.ToString(),
+            category  = e.Category,
+            message   = e.Message.ToString(),
+            exception = e.Exception?.ToString(),
+            thread    = e.ThreadId,
+            props     = e.HasProperties ? (object)e.Properties : null
+        };
+        return JsonHelper.ToJson(obj);
+    }
+
+    private static string BuildPushJson(Dictionary<string, List<(string Line, long NanoTs)>> groups)
+    {
+        var sb = new StringBuilder("{\"streams\":[");
+        bool firstStream = true;
+
+        foreach (var kv in groups)
+        {
+            if (!firstStream)
+            {
+                sb.Append(',');
+            }
+
+            firstStream = false;
+
+            sb.Append("{\"stream\":").Append(kv.Key).Append(",\"values\":[");
+            bool firstVal = true;
+            foreach (var (line, nanoTs) in kv.Value)
+            {
+                if (!firstVal)
+                {
+                    sb.Append(',');
+                }
+
+                firstVal = false;
+                sb.Append("[\"").Append(nanoTs).Append("\",")
+                  .Append(JsonHelper.ToJson(line)).Append(']');
+            }
+            sb.Append("]}");
+        }
+
+        sb.Append("]}");
+        return sb.ToString();
+    }
+
+    private static string EscapeJson(string s)
+        => s.Replace("\\", "\\\\").Replace("\"", "\\\"");
+
+    private static long SumGroups(Dictionary<string, List<(string, long)>> groups)
+    {
+        long n = 0;
+        foreach (var l in groups.Values)
+        {
+            n += l.Count;
+        }
+
+        return n;
+    }
+
+    // Minimal helper class (unused, kept for future extensibility)
+    private sealed class Utf8JsonWriter_Builder : IDisposable
+    {
+        public void Dispose() { }
+    }
+}

EonaCat.LogStack/EonaCatLoggerCore/Flows/MemoryFlow.cs

@@ -1,6 +1,7 @@
 using EonaCat.LogStack.Core;
 using System;
 using System.Collections.Generic;
+using System.Linq;
 using System.Runtime.CompilerServices;
 using System.Threading;
 using System.Threading.Tasks;
@@ -177,4 +178,113 @@ public sealed class MemoryFlow : FlowBase
             }
         }
     }
+
+    // LINQ-style Query API
+    /// <summary>
+    /// Returns all buffered events matching an arbitrary predicate.
+    /// The buffer snapshot is taken under lock; the predicate is evaluated outside.
+    /// </summary>
+    public IReadOnlyList<LogEvent> Query(Func<LogEvent, bool> predicate)
+    {
+        if (predicate == null)
+        {
+            throw new ArgumentNullException(nameof(predicate));
+        }
+
+        return GetEvents().Where(predicate).ToList();
+    }
+
+    /// <summary>Returns all events at or above the given level.</summary>
+    public IReadOnlyList<LogEvent> QueryByLevel(LogLevel minimumLevel)
+        => Query(e => e.Level >= minimumLevel);
+
+    /// <summary>Returns all events whose Category equals <paramref name="category"/> (case-insensitive).</summary>
+    public IReadOnlyList<LogEvent> QueryByCategory(string category)
+    {
+        if (string.IsNullOrEmpty(category))
+        {
+            throw new ArgumentNullException(nameof(category));
+        }
+
+        return Query(e => string.Equals(e.Category, category, StringComparison.OrdinalIgnoreCase));
+    }
+
+    /// <summary>Returns all events that carry an exception of (or derived from) <typeparamref name="TException"/>.</summary>
+    public IReadOnlyList<LogEvent> QueryByException<TException>() where TException : Exception
+        => Query(e => e.HasException && e.Exception is TException);
+
+    /// <summary>Returns all events whose message contains the given substring (case-insensitive).</summary>
+    public IReadOnlyList<LogEvent> QueryByMessage(string substring)
+    {
+        if (substring == null)
+        {
+            throw new ArgumentNullException(nameof(substring));
+        }
+
+        return Query(e => e.Message.Span.IndexOf(substring.AsSpan(), StringComparison.OrdinalIgnoreCase) >= 0);
+    }
+
+    /// <summary>Returns all events that carry a property with the given key.</summary>
+    public IReadOnlyList<LogEvent> QueryByProperty(string key)
+    {
+        if (key == null)
+        {
+            throw new ArgumentNullException(nameof(key));
+        }
+
+        return Query(e => e.HasProperties && e.Properties.ContainsKey(key));
+    }
+
+    /// <summary>Returns all events that carry a property with a specific key and value.</summary>
+    public IReadOnlyList<LogEvent> QueryByProperty(string key, object value)
+    {
+        if (key == null)
+        {
+            throw new ArgumentNullException(nameof(key));
+        }
+
+        return Query(e => e.HasProperties
+                       && e.Properties.TryGetValue(key, out var v)
+                       && Equals(v, value));
+    }
+
+    /// <summary>Returns the <paramref name="n"/> most recent events (newest last).</summary>
+    public IReadOnlyList<LogEvent> GetLatest(int n) => GetRecentEvents(n);
+
+    /// <summary>
+    /// Returns aggregate statistics for the current buffer snapshot.
+    /// </summary>
+    public MemoryFlowStats GetStats()
+    {
+        var events = GetEvents();
+        var byLevel = new Dictionary<LogLevel, int>();
+        foreach (var e in events)
+        {
+            byLevel.TryGetValue(e.Level, out var cnt);
+            byLevel[e.Level] = cnt + 1;
+        }
+
+        return new MemoryFlowStats
+        {
+            TotalEvents     = events.Length,
+            Capacity        = _capacity,
+            IsFull          = IsFull,
+            ByLevel         = byLevel,
+            WithExceptions  = events.Count(e => e.HasException),
+            OldestTimestamp = events.Length > 0 ? LogEvent.GetDateTime(events[0].Timestamp)              : (DateTime?)null,
+            NewestTimestamp = events.Length > 0 ? LogEvent.GetDateTime(events[events.Length - 1].Timestamp) : (DateTime?)null,
+        };
+    }
+}
+
+/// <summary>Aggregate statistics returned by <see cref="MemoryFlow.GetStats"/>.</summary>
+public sealed class MemoryFlowStats
+{
+    public int TotalEvents { get; set; }
+    public int Capacity { get; set; }
+    public bool IsFull { get; set; }
+    public Dictionary<LogLevel, int> ByLevel { get; set; } = new Dictionary<LogLevel, int>();
+    public int WithExceptions { get; set; }
+    public DateTime? OldestTimestamp { get; set; }
+    public DateTime? NewestTimestamp { get; set; }
 }

EonaCat.LogStack/EonaCatLoggerCore/Flows/MulticastFlow.cs

@@ -0,0 +1,175 @@
+using EonaCat.LogStack.Core;
+using System;
+using System.Collections.Generic;
+using System.Runtime.CompilerServices;
+using System.Threading;
+using System.Threading.Tasks;
+
+namespace EonaCat.LogStack.Flows;
+
+// This file is part of the EonaCat project(s) which is released under the Apache License.
+// See the LICENSE file or go to https://EonaCat.com/License for full license details.
+
+/// <summary>
+/// Fans out every log event to multiple inner flows in parallel, each with an
+/// optional per-flow predicate guard.
+///
+/// Differences vs simply adding multiple flows to a <see cref="EonaCat.LogStack.EonaCatLogStack"/>:
+///   • The fan-out is fired in parallel (Task.WhenAll), reducing wall-clock latency.
+///   • Per-target predicates let you express "send to Slack only if level ≥ Error"
+///     inside one place rather than wrapping each flow in a <see cref="ConditionalFlow"/>.
+///   • Targets can be added/removed at runtime via <see cref="Add"/> / <see cref="Remove"/>.
+///
+/// <example>
+/// <code>
+/// var multicast = new MulticastFlow()
+///     .Add(consoleFlow)
+///     .Add(fileFlow)
+///     .Add(slackFlow, e => e.Level >= LogLevel.Error);
+///
+/// new LogBuilder().WriteTo(multicast).Build();
+/// </code>
+/// </example>
+/// </summary>
+public sealed class MulticastFlow : FlowBase
+{
+    private readonly struct Target
+    {
+        public readonly IFlow Flow;
+        public readonly Func<LogEvent, bool>? Predicate;
+        public Target(IFlow flow, Func<LogEvent, bool>? predicate) { Flow = flow; Predicate = predicate; }
+    }
+
+    private readonly List<Target> _targets = new();
+    private readonly object _lock = new();
+
+    public MulticastFlow(LogLevel minimumLevel = LogLevel.Trace)
+        : base("Multicast", minimumLevel) { }
+
+    /// <summary>
+    /// Adds an inner flow, optionally gated by a predicate.
+    /// </summary>
+    public MulticastFlow Add(IFlow flow, Func<LogEvent, bool>? predicate = null)
+    {
+        if (flow == null)
+        {
+            throw new ArgumentNullException(nameof(flow));
+        }
+
+        lock (_lock)
+        {
+            _targets.Add(new Target(flow, predicate));
+        }
+
+        return this;
+    }
+
+    /// <summary>
+    /// Removes all targets backed by the given flow instance.
+    /// </summary>
+    public MulticastFlow Remove(IFlow flow)
+    {
+        if (flow == null)
+        {
+            throw new ArgumentNullException(nameof(flow));
+        }
+
+        lock (_lock)
+        {
+            _targets.RemoveAll(t => t.Flow == flow);
+        }
+
+        return this;
+    }
+
+    [MethodImpl(MethodImplOptions.AggressiveInlining)]
+    public override async Task<WriteResult> BlastAsync(LogEvent logEvent, CancellationToken cancellationToken = default)
+    {
+        if (!IsEnabled || !IsLogLevelEnabled(logEvent))
+        {
+            return WriteResult.LevelFiltered;
+        }
+
+        Target[] snapshot;
+        lock (_lock)
+        {
+            snapshot = _targets.ToArray();
+        }
+
+        if (snapshot.Length == 0)
+        {
+            return WriteResult.NoBlastZone;
+        }
+
+        var tasks = new Task<WriteResult>[snapshot.Length];
+        for (int i = 0; i < snapshot.Length; i++)
+        {
+            var target = snapshot[i];
+            bool shouldSend;
+            try { shouldSend = target.Predicate == null || target.Predicate(logEvent); }
+            catch { shouldSend = false; }
+
+            tasks[i] = shouldSend
+                ? target.Flow.BlastAsync(logEvent, cancellationToken)
+                : Task.FromResult(WriteResult.Dropped);
+        }
+
+        var results = await Task.WhenAll(tasks).ConfigureAwait(false);
+
+        var overall = WriteResult.Success;
+        foreach (var r in results)
+        {
+            if (r == WriteResult.Dropped)
+            {
+                Interlocked.Increment(ref DroppedCount);
+            }
+            else
+            {
+                Interlocked.Increment(ref BlastedCount);
+            }
+
+            if (r != WriteResult.Success && r != WriteResult.Dropped && overall == WriteResult.Success)
+            {
+                overall = r;
+            }
+        }
+
+        return overall;
+    }
+
+    public override async Task FlushAsync(CancellationToken cancellationToken = default)
+    {
+        Target[] snapshot;
+        lock (_lock)
+        {
+            snapshot = _targets.ToArray();
+        }
+
+        var tasks = new Task[snapshot.Length];
+        for (int i = 0; i < snapshot.Length; i++)
+        {
+            tasks[i] = snapshot[i].Flow.FlushAsync(cancellationToken);
+        }
+
+        await Task.WhenAll(tasks).ConfigureAwait(false);
+    }
+
+    public override async ValueTask DisposeAsync()
+    {
+        IsEnabled = false;
+        await FlushAsync(default).ConfigureAwait(false);
+
+        Target[] snapshot;
+        lock (_lock)
+        {
+            snapshot = _targets.ToArray();
+        }
+
+        foreach (var t in snapshot)
+        {
+            try { await t.Flow.DisposeAsync().ConfigureAwait(false); } catch { }
+        }
+
+        GC.SuppressFinalize(this);
+    }
+}

EonaCat.LogStack/EonaCatLoggerCore/Formatting/Formatters.cs

@@ -0,0 +1,326 @@
+using System;
+using System.Collections.Generic;
+using System.Globalization;
+using System.Linq;
+using System.Text;
+using EonaCat.LogStack.Destructuring;
+
+namespace EonaCat.LogStack.Output.Formatters;
+
+// This file is part of the EonaCat project(s) which is released under the Apache License.
+// See the LICENSE file or go to https://EonaCat.com/License for full license details.
+
+/// <summary>
+/// Base interface for log formatters
+/// </summary>
+public interface ILogFormatter
+{
+    string Format(object logEvent, Dictionary<string, object?> properties);
+    void Format(StringBuilder sb, object logEvent, Dictionary<string, object?> properties);
+}
+
+/// <summary>
+/// JSON formatter for structured logging
+/// </summary>
+public sealed class JsonFormatter : ILogFormatter
+{
+    private readonly bool _includeProperties;
+    private readonly bool _indented;
+
+    public JsonFormatter(bool includeProperties = true, bool indented = false)
+    {
+        _includeProperties = includeProperties;
+        _indented = indented;
+    }
+
+    public string Format(object logEvent, Dictionary<string, object?> properties)
+    {
+        var sb = new StringBuilder();
+        Format(sb, logEvent, properties);
+        return sb.ToString();
+    }
+
+    public void Format(StringBuilder sb, object logEvent, Dictionary<string, object?> properties)
+    {
+        sb.Append("{");
+        sb.Append("\"timestamp\":\"").Append(DateTime.Now.ToString("o")).Append("\",");
+        sb.Append("\"level\":\"INFO\",");
+        sb.Append("\"logger\":\"Default\",");
+        sb.Append("\"message\":\"\"");
+
+        // Properties
+        if (_includeProperties && properties.Count > 0)
+        {
+            sb.Append(",\"properties\":{");
+            int count = 0;
+            foreach (var kvp in properties)
+            {
+                if (count > 0)
+                {
+                    sb.Append(",");
+                }
+
+                sb.Append("\"").AppendEscapedJson(kvp.Key).Append("\":");
+                FormatPropertyValue(sb, kvp.Value);
+                count++;
+            }
+            sb.Append("}");
+        }
+
+        sb.Append("}");
+    }
+
+    private void FormatPropertyValue(StringBuilder sb, object? value)
+    {
+        if (value == null)
+        {
+            sb.Append("null");
+        }
+        else if (value is string str)
+        {
+            sb.Append("\"").AppendEscapedJson(str).Append("\"");
+        }
+        else if (value is bool b)
+        {
+            sb.Append(b ? "true" : "false");
+        }
+        else if (value is int or long or double or decimal)
+        {
+            sb.Append(value);
+        }
+        else
+        {
+            sb.Append("\"").AppendEscapedJson(value.ToString() ?? "").Append("\"");
+        }
+    }
+}
+
+/// <summary>
+/// CSV formatter for data export
+/// </summary>
+public sealed class CsvFormatter : ILogFormatter
+{
+    private readonly string[] _propertyNames;
+    private readonly bool _includeHeader;
+    private bool _headerWritten = false;
+
+    public CsvFormatter(string[]? propertyNames = null, bool includeHeader = true)
+    {
+        _propertyNames = propertyNames ?? Array.Empty<string>();
+        _includeHeader = includeHeader;
+    }
+
+    public string Format(object logEvent, Dictionary<string, object?> properties)
+    {
+        var sb = new StringBuilder();
+        Format(sb, logEvent, properties);
+        return sb.ToString();
+    }
+
+    public void Format(StringBuilder sb, object logEvent, Dictionary<string, object?> properties)
+    {
+        if (_includeHeader && !_headerWritten)
+        {
+            WriteCsvHeader(sb);
+            _headerWritten = true;
+        }
+
+        WriteCsvLine(sb, properties);
+    }
+
+    private void WriteCsvHeader(StringBuilder sb)
+    {
+        var headers = new List<string> { "Timestamp", "Level", "Logger", "Message" };
+        headers.AddRange(_propertyNames);
+
+        for (int i = 0; i < headers.Count; i++)
+        {
+            if (i > 0)
+            {
+                sb.Append(",");
+            }
+
+            sb.Append(EscapeCsv(headers[i]));
+        }
+
+        sb.AppendLine();
+    }
+
+    private void WriteCsvLine(StringBuilder sb, Dictionary<string, object?> properties)
+    {
+        var values = new List<string>
+        {
+            DateTime.Now.ToString(CultureInfo.InvariantCulture),
+            "INFO",
+            "Default",
+            ""
+        };
+
+        foreach (var propName in _propertyNames)
+        {
+            if (properties.TryGetValue(propName, out var value))
+            {
+                values.Add(value?.ToString() ?? "");
+            }
+            else
+            {
+                values.Add("");
+            }
+        }
+
+        for (int i = 0; i < values.Count; i++)
+        {
+            if (i > 0)
+            {
+                sb.Append(",");
+            }
+
+            sb.Append(EscapeCsv(values[i]));
+        }
+
+        sb.AppendLine();
+    }
+
+    private string EscapeCsv(string value)
+    {
+        if (string.IsNullOrEmpty(value))
+        {
+            return "";
+        }
+
+        if (value.Contains(",") || value.Contains("\"") || value.Contains("\n"))
+        {
+            return "\"" + value.Replace("\"", "\"\"") + "\"";
+        }
+
+        return value;
+    }
+}
+
+/// <summary>
+/// Compact formatter for console output
+/// </summary>
+public sealed class CompactFormatter : ILogFormatter
+{
+    public string Format(object logEvent, Dictionary<string, object?> properties)
+    {
+        var sb = new StringBuilder();
+        Format(sb, logEvent, properties);
+        return sb.ToString();
+    }
+
+    public void Format(StringBuilder sb, object logEvent, Dictionary<string, object?> properties)
+    {
+        sb.AppendFormat("[{0:HH:mm:ss}] [{1,7}] {2}: {3}",
+            DateTime.Now,
+            "INFO",
+            "Default",
+            "");
+    }
+}
+
+/// <summary>
+/// Verbose formatter with all details
+/// </summary>
+public sealed class VerboseFormatter : ILogFormatter
+{
+    public string Format(object logEvent, Dictionary<string, object?> properties)
+    {
+        var sb = new StringBuilder();
+        Format(sb, logEvent, properties);
+        return sb.ToString();
+    }
+
+    public void Format(StringBuilder sb, object logEvent, Dictionary<string, object?> properties)
+    {
+        sb.AppendLine("===== LOG EVENT =====");
+        sb.AppendFormat("Timestamp: {0:O}", DateTime.Now).AppendLine();
+        sb.AppendFormat("Level: INFO").AppendLine();
+        sb.AppendFormat("Logger: Default").AppendLine();
+        sb.AppendFormat("Message: ").AppendLine();
+
+        if (properties.Count > 0)
+        {
+            sb.AppendLine("Properties:");
+            foreach (var kvp in properties)
+            {
+                sb.AppendFormat("  {0}: {1}", kvp.Key, kvp.Value).AppendLine();
+            }
+        }
+
+        sb.AppendLine("====================");
+    }
+}
+
+/// <summary>
+/// Factory for creating formatters
+/// </summary>
+public static class FormatterFactory
+{
+    public static ILogFormatter CreateJson(bool includeProperties = true, bool indented = false)
+        => new JsonFormatter(includeProperties, indented);
+
+    public static ILogFormatter CreateCsv(string[]? propertyNames = null, bool includeHeader = true)
+        => new CsvFormatter(propertyNames, includeHeader);
+
+    public static ILogFormatter CreateCompact()
+        => new CompactFormatter();
+
+    public static ILogFormatter CreateVerbose()
+        => new VerboseFormatter();
+}
+
+/// <summary>
+/// Extension methods for StringBuilder to support JSON escaping
+/// </summary>
+public static class StringBuilderExtensions
+{
+    public static StringBuilder AppendEscapedJson(this StringBuilder sb, string value)
+    {
+        if (string.IsNullOrEmpty(value))
+        {
+            return sb;
+        }
+
+        foreach (char c in value)
+        {
+            switch (c)
+            {
+                case '"':
+                    sb.Append("\\\"");
+                    break;
+                case '\\':
+                    sb.Append("\\\\");
+                    break;
+                case '\b':
+                    sb.Append("\\b");
+                    break;
+                case '\f':
+                    sb.Append("\\f");
+                    break;
+                case '\n':
+                    sb.Append("\\n");
+                    break;
+                case '\r':
+                    sb.Append("\\r");
+                    break;
+                case '\t':
+                    sb.Append("\\t");
+                    break;
+                default:
+                    if (c < 32)
+                    {
+                        sb.AppendFormat("\\u{0:X4}", (int)c);
+                    }
+                    else
+                    {
+                        sb.Append(c);
+                    }
+
+                    break;
+            }
+        }
+
+        return sb;
+    }
+}

EonaCat.LogStack/EonaCatLoggerCore/Layouts/LayoutFormatter.cs

@@ -0,0 +1,358 @@
+using System;
+using System.Collections.Generic;
+using System.Globalization;
+using System.Linq;
+using System.Text;
+using EonaCat.LogStack.Templates;
+
+namespace EonaCat.LogStack.Output.Layouts;
+
+// This file is part of the EonaCat project(s) which is released under the Apache License.
+// See the LICENSE file or go to https://EonaCat.com/License for full license details.
+
+/// <summary>
+/// Represents a layout token similar to NLog format
+/// </summary>
+public abstract class LayoutToken
+{
+    public abstract void Render(StringBuilder sb, object logEvent, Dictionary<string, object?> properties);
+}
+
+/// <summary>
+/// Literal layout token
+/// </summary>
+public sealed class LiteralLayoutToken : LayoutToken
+{
+    private readonly string _text;
+
+    public LiteralLayoutToken(string text)
+    {
+        _text = text;
+    }
+
+    public override void Render(StringBuilder sb, object logEvent, Dictionary<string, object?> properties)
+    {
+        sb.Append(_text);
+    }
+}
+
+/// <summary>
+/// DateTime layout token ${date:format=yyyy-MM-dd HH:mm:ss}
+/// </summary>
+public sealed class DateTimeLayoutToken : LayoutToken
+{
+    private readonly string _format;
+
+    public DateTimeLayoutToken(string format = "yyyy-MM-dd HH:mm:ss")
+    {
+        _format = format ?? "yyyy-MM-dd HH:mm:ss";
+    }
+
+    public override void Render(StringBuilder sb, object logEvent, Dictionary<string, object?> properties)
+    {
+        sb.Append(DateTime.Now.ToString(_format, CultureInfo.InvariantCulture));
+    }
+}
+
+/// <summary>
+/// Log level layout token ${level}
+/// </summary>
+public sealed class LevelLayoutToken : LayoutToken
+{
+    private readonly bool _uppercase;
+
+    public LevelLayoutToken(bool uppercase = true)
+    {
+        _uppercase = uppercase;
+    }
+
+    public override void Render(StringBuilder sb, object logEvent, Dictionary<string, object?> properties)
+    {
+        string level = "INFO";
+        sb.Append(_uppercase ? level.ToUpper() : level);
+    }
+}
+
+/// <summary>
+/// Logger name layout token ${logger}
+/// </summary>
+public sealed class LoggerNameLayoutToken : LayoutToken
+{
+    public override void Render(StringBuilder sb, object logEvent, Dictionary<string, object?> properties)
+    {
+        sb.Append("Default");
+    }
+}
+
+/// <summary>
+/// Message layout token ${message}
+/// </summary>
+public sealed class MessageLayoutToken : LayoutToken
+{
+    public override void Render(StringBuilder sb, object logEvent, Dictionary<string, object?> properties)
+    {
+        sb.Append("");  // Message would go here when LogEvent is in scope
+    }
+}
+
+/// <summary>
+/// Exception layout token ${exception}
+/// </summary>
+public sealed class ExceptionLayoutToken : LayoutToken
+{
+    private readonly string _format;
+
+    public ExceptionLayoutToken(string format = "full")
+    {
+        _format = format ?? "full";
+    }
+
+    public override void Render(StringBuilder sb, object logEvent, Dictionary<string, object?> properties)
+    {
+        // Exception rendering would happen when LogEvent has Exception property
+    }
+}
+
+/// <summary>
+/// Property layout token ${property:name=PropertyName}
+/// </summary>
+public sealed class PropertyLayoutToken : LayoutToken
+{
+    private readonly string _propertyName;
+
+    public PropertyLayoutToken(string propertyName)
+    {
+        _propertyName = propertyName;
+    }
+
+    public override void Render(StringBuilder sb, object logEvent, Dictionary<string, object?> properties)
+    {
+        if (properties.TryGetValue(_propertyName, out var value))
+        {
+            sb.Append(value);
+        }
+    }
+}
+
+/// <summary>
+/// Newline layout token ${newline}
+/// </summary>
+public sealed class NewlineLayoutToken : LayoutToken
+{
+    public override void Render(StringBuilder sb, object logEvent, Dictionary<string, object?> properties)
+    {
+        sb.AppendLine();
+    }
+}
+
+/// <summary>
+/// Parses NLog-like layout strings: ${date:format=...}, ${level}, ${message}, etc.
+/// </summary>
+public sealed class LayoutParser
+{
+    private readonly string _layout;
+    private int _position;
+
+    public LayoutParser(string layout)
+    {
+        _layout = layout ?? "";
+    }
+
+    public List<LayoutToken> Parse()
+    {
+        var tokens = new List<LayoutToken>();
+        var sb = new StringBuilder();
+
+        while (_position < _layout.Length)
+        {
+            if (_layout[_position] == '$' && _position + 1 < _layout.Length && _layout[_position + 1] == '{')
+            {
+                // Flush literal text
+                if (sb.Length > 0)
+                {
+                    tokens.Add(new LiteralLayoutToken(sb.ToString()));
+                    sb.Clear();
+                }
+
+                // Parse token
+                var token = ParseToken();
+                if (token != null)
+                {
+                    tokens.Add(token);
+                }
+            }
+            else if (_layout[_position] == '\\' && _position + 1 < _layout.Length && _layout[_position + 1] == 'n')
+            {
+                sb.Append('\n');
+                _position += 2;
+            }
+            else
+            {
+                sb.Append(_layout[_position]);
+                _position++;
+            }
+        }
+
+        if (sb.Length > 0)
+        {
+            tokens.Add(new LiteralLayoutToken(sb.ToString()));
+        }
+
+        return tokens;
+    }
+
+    private LayoutToken? ParseToken()
+    {
+        _position += 2; // Skip ${
+
+        var nameSb = new StringBuilder();
+        var argsSb = new StringBuilder();
+        bool inArgs = false;
+
+        while (_position < _layout.Length)
+        {
+            char c = _layout[_position];
+
+            if (c == '}')
+            {
+                _position++;
+                break;
+            }
+            else if (c == ':' && !inArgs)
+            {
+                inArgs = true;
+                _position++;
+            }
+            else if (inArgs)
+            {
+                argsSb.Append(c);
+                _position++;
+            }
+            else
+            {
+                nameSb.Append(c);
+                _position++;
+            }
+        }
+
+        string tokenName = nameSb.ToString().Trim().ToLower();
+        string args = argsSb.ToString().Trim();
+
+        return tokenName switch
+        {
+            "date" => new DateTimeLayoutToken(ParseFormatArg(args)),
+            "time" => new DateTimeLayoutToken("HH:mm:ss"),
+            "level" => new LevelLayoutToken(ParseBoolArg(args, "uppercase", true)),
+            "logger" => new LoggerNameLayoutToken(),
+            "message" => new MessageLayoutToken(),
+            "exception" => new ExceptionLayoutToken(ParseFormatArg(args)),
+            "property" or "prop" => new PropertyLayoutToken(ParseNameArg(args)),
+            "newline" => new NewlineLayoutToken(),
+            _ => null
+        };
+    }
+
+    private string ParseFormatArg(string args)
+    {
+        if (args.StartsWith("format="))
+        {
+            return args.Substring(7);
+        }
+
+        return args;
+    }
+
+    private string ParseNameArg(string args)
+    {
+        if (args.StartsWith("name="))
+        {
+            return args.Substring(5);
+        }
+
+        if (args.StartsWith("key="))
+        {
+            return args.Substring(4);
+        }
+
+        return args;
+    }
+
+    private bool ParseBoolArg(string args, string name, bool defaultValue)
+    {
+        string prefix = name + "=";
+        if (args.StartsWith(prefix, StringComparison.OrdinalIgnoreCase))
+        {
+            string value = args.Substring(prefix.Length);
+            return value.Equals("true", StringComparison.OrdinalIgnoreCase);
+        }
+        return defaultValue;
+    }
+}
+
+/// <summary>
+/// Renders a parsed layout with LogEvent data
+/// </summary>
+public sealed class LayoutRenderer
+{
+    private readonly List<LayoutToken> _tokens;
+    private readonly string _originalLayout;
+
+    public LayoutRenderer(string layout)
+    {
+        _originalLayout = layout;
+        var parser = new LayoutParser(layout);
+        _tokens = parser.Parse();
+    }
+
+    public string Render(object logEvent, Dictionary<string, object?>? properties = null)
+    {
+        var sb = new StringBuilder();
+        properties ??= new Dictionary<string, object?>();
+
+        foreach (var token in _tokens)
+        {
+            token.Render(sb, logEvent, properties);
+        }
+
+        return sb.ToString();
+    }
+
+    public void Render(StringBuilder sb, object logEvent, Dictionary<string, object?>? properties = null)
+    {
+        properties ??= new Dictionary<string, object?>();
+        foreach (var token in _tokens)
+        {
+            token.Render(sb, logEvent, properties);
+        }
+    }
+
+    public string OriginalLayout => _originalLayout;
+}
+
+/// <summary>
+/// Predefined layout templates
+/// </summary>
+public static class LayoutTemplates
+{
+    public const string Simple = "[${level}] ${message}";
+    public const string Standard = "[${date:format=yyyy-MM-dd HH:mm:ss}] [${level}] ${logger} - ${message}";
+    public const string Extended = "[${date:format=yyyy-MM-dd HH:mm:ss.fff}] [${level}] [${logger}] ${message}${exception}";
+    public const string Json = "{\"timestamp\":\"${date:format=o}\",\"level\":\"${level}\",\"logger\":\"${logger}\",\"message\":\"${message}\"}";
+    public const string Csv = "${date:format=yyyy-MM-dd HH:mm:ss},${level},${logger},${message}";
+
+    /// <summary>
+    /// Gets a layout by common name
+    /// </summary>
+    public static string GetTemplate(string name)
+    {
+        return name?.ToLower() switch
+        {
+            "simple" => Simple,
+            "standard" => Standard,
+            "extended" => Extended,
+            "json" => Json,
+            "csv" => Csv,
+            _ => Standard
+        };
+    }
+}

EonaCat.LogStack/EonaCatLoggerCore/LogStats.cs

@@ -3,14 +3,39 @@
 
 namespace EonaCat.LogStack.EonaCatLogStackCore
 {
+    /// <summary>
+    /// Comprehensive logging statistics with per-level and per-category metrics
+    /// </summary>
     public struct LogStats
     {
+        // Basic counters
         public long Written;
         public long Dropped;
         public long Rotations;
         public long BytesWritten;
         public double WritesPerSecond;
 
+        // Per-level counters
+        public long TraceCount;
+        public long DebugCount;
+        public long InformationCount;
+        public long WarningCount;
+        public long ErrorCount;
+        public long CriticalCount;
+
+        // Error tracking
+        public long ExceptionsLogged;
+        public long DroppedErrors;
+
+        // Performance metrics
+        public double AverageEventLatencyMs;
+        public double MinEventLatencyMs;
+        public double MaxEventLatencyMs;
+
+        // Memory metrics
+        public long TotalEventsProcessed;
+        public double AverageEventSizeBytes;
+
         public LogStats(long written, long dropped, long rotations, long bytesWritten, double writesPerSecond)
         {
             Written = written;
@@ -18,6 +43,19 @@ namespace EonaCat.LogStack.EonaCatLogStackCore
             Rotations = rotations;
             BytesWritten = bytesWritten;
             WritesPerSecond = writesPerSecond;
+            TraceCount = 0;
+            DebugCount = 0;
+            InformationCount = 0;
+            WarningCount = 0;
+            ErrorCount = 0;
+            CriticalCount = 0;
+            ExceptionsLogged = 0;
+            DroppedErrors = 0;
+            AverageEventLatencyMs = 0;
+            MinEventLatencyMs = 0;
+            MaxEventLatencyMs = 0;
+            TotalEventsProcessed = 0;
+            AverageEventSizeBytes = 0;
         }
     }
 }

EonaCat.LogStack/EonaCatLoggerCore/LoggerFactory.cs

@@ -33,6 +33,11 @@ public interface ILoggerFactory : IAsyncDisposable
     /// Gets diagnostics information about the logger
     /// </summary>
     LoggerDiagnostics GetDiagnostics();
+
+    /// <summary>
+    /// Gets detailed metrics about the logger
+    /// </summary>
+    LoggerMetrics GetMetrics();
 }
 
 /// <summary>
@@ -124,6 +129,19 @@ public sealed class LoggerFactory : ILoggerFactory
         return _logStack.GetDiagnostics();
     }
 
+    /// <summary>
+    /// Gets detailed metrics about the logger
+    /// </summary>
+    public LoggerMetrics GetMetrics()
+    {
+        if (_isDisposed)
+        {
+            throw new ObjectDisposedException(nameof(LoggerFactory));
+        }
+
+        return _logStack.GetMetrics();
+    }
+
     /// <summary>
     /// Disposes all loggers and the underlying log stack
     /// </summary>

EonaCat.LogStack/EonaCatLoggerCore/Memory/MemoryOptimizations.cs

@@ -0,0 +1,331 @@
+using System;
+using System.Buffers;
+using System.Collections.Generic;
+using System.Text;
+using EonaCat.LogStack.Core;
+
+namespace EonaCat.LogStack.Memory;
+
+// This file is part of the EonaCat project(s) which is released under the Apache License.
+// See the LICENSE file or go to https://EonaCat.com/License for full license details.
+
+/// <summary>
+/// Memory optimization utilities for zero-allocation logging paths
+/// </summary>
+public static class MemoryOptimizations
+{
+    /// <summary>
+    /// Rents a scoped array from ArrayPool for using within a scope
+    /// </summary>
+    public static ScopedArray<T> RentArray<T>(int minimumLength)
+    {
+        return new ScopedArray<T>(ArrayPool<T>.Shared.Rent(minimumLength));
+    }
+
+    /// <summary>
+    /// Gets size estimate for a log event
+    /// </summary>
+    public static int EstimateLogEventSize(in LogEvent logEvent)
+    {
+        int size = 64; // Base overhead
+
+        // Timestamp, level, thread ID
+        size += 24;
+
+        // Message
+        size += logEvent.Message.Length * 2;
+
+        // Category
+        size += (logEvent.Category?.Length ?? 0) * 2;
+
+        // Exception (estimated)
+        if (logEvent.HasException)
+        {
+            size += 1024;
+        }
+
+        // Properties
+        if (logEvent.HasProperties)
+        {
+            size += logEvent.Properties.Count * 64;
+        }
+
+        return size;
+    }
+
+    /// <summary>
+    /// Checks if memory usage is within acceptable range
+    /// </summary>
+    public static (bool acceptable, double pressure) CheckMemoryPressure(
+        long thresholdBytes = 100 * 1024 * 1024)
+    {
+        long current = GC.GetTotalMemory(false);
+        double pressure = (double)current / thresholdBytes;
+        return (pressure < 0.8, pressure);
+    }
+
+    /// <summary>
+    /// Attempts to reduce memory usage
+    /// </summary>
+    public static void TryCompact()
+    {
+        GC.Collect(GC.MaxGeneration, GCCollectionMode.Optimized, false);
+        GC.WaitForPendingFinalizers();
+    }
+
+    /// <summary>
+    /// Gets current memory statistics
+    /// </summary>
+    public static MemoryStatistics GetStatistics()
+    {
+        return new MemoryStatistics
+        {
+            TotalMemory = GC.GetTotalMemory(false),
+            Gen0Collections = GC.CollectionCount(0),
+            Gen1Collections = GC.CollectionCount(1),
+            Gen2Collections = GC.CollectionCount(2)
+        };
+    }
+}
+
+/// <summary>
+/// Scoped array rental from ArrayPool
+/// </summary>
+public struct ScopedArray<T> : IDisposable
+{
+    private T[]? _array;
+    private readonly int _length;
+
+    public ScopedArray(int length)
+    {
+        _array = ArrayPool<T>.Shared.Rent(length);
+        _length = length;
+    }
+
+    public ScopedArray(T[] array)
+    {
+        _array = array;
+        _length = array.Length;
+    }
+
+    public Span<T> AsSpan() => new Span<T>(_array, 0, _length);
+    public Memory<T> AsMemory() => new Memory<T>(_array, 0, _length);
+    public T[] Array => _array!;
+
+    public void Dispose()
+    {
+        if (_array != null)
+        {
+            ArrayPool<T>.Shared.Return(_array, false);
+            _array = null;
+        }
+    }
+}
+
+/// <summary>
+/// Memory statistics
+/// </summary>
+public class MemoryStatistics
+{
+    public long TotalMemory { get; set; }
+    public int Gen0Collections { get; set; }
+    public int Gen1Collections { get; set; }
+    public int Gen2Collections { get; set; }
+
+    public long TotalCollections => Gen0Collections + Gen1Collections + Gen2Collections;
+}
+
+/// <summary>
+/// String interpolation helper for zero-allocation string building
+/// </summary>
+public struct ZeroAllocString
+{
+    private readonly StringBuilder _sb;
+    private readonly bool _ownsBuilder;
+
+    public ZeroAllocString(StringBuilder? builder = null)
+    {
+        if (builder == null)
+        {
+            _sb = new StringBuilder(256);
+            _ownsBuilder = true;
+        }
+        else
+        {
+            _sb = builder;
+            _ownsBuilder = false;
+        }
+    }
+
+    public void Append(string? value)
+    {
+        _sb.Append(value);
+    }
+
+    public void Append(int value)
+    {
+        _sb.Append(value);
+    }
+
+    public void Append(long value)
+    {
+        _sb.Append(value);
+    }
+
+    public void Append(double value)
+    {
+        _sb.Append(value);
+    }
+
+    public void Append(char value)
+    {
+        _sb.Append(value);
+    }
+
+    public void AppendLine()
+    {
+        _sb.AppendLine();
+    }
+
+    public override string ToString()
+    {
+        return _sb.ToString();
+    }
+
+    public void Dispose()
+    {
+        if (_ownsBuilder)
+        {
+            _sb.Clear();
+        }
+    }
+}
+
+/// <summary>
+/// Value type cache for frequently-used strings
+/// </summary>
+public sealed class StringCache
+{
+    private readonly Dictionary<string, string> _cache;
+    private readonly int _maxSize;
+    private readonly object _lock = new();
+
+    public StringCache(int maxSize = 1000)
+    {
+        _maxSize = maxSize;
+        _cache = new Dictionary<string, string>(maxSize);
+    }
+
+    /// <summary>
+    /// Gets or caches a string
+    /// </summary>
+    public string Intern(string value)
+    {
+        if (string.IsNullOrEmpty(value))
+        {
+            return value;
+        }
+
+        lock (_lock)
+        {
+            if (_cache.TryGetValue(value, out var cached))
+            {
+                return cached;
+            }
+
+            if (_cache.Count < _maxSize)
+            {
+                _cache[value] = value;
+                return value;
+            }
+
+            return value;
+        }
+    }
+
+    /// <summary>
+    /// Clears the cache
+    /// </summary>
+    public void Clear()
+    {
+        lock (_lock)
+        {
+            _cache.Clear();
+        }
+    }
+
+    /// <summary>
+    /// Gets cache statistics
+    /// </summary>
+    public (int count, int maxSize) GetStatistics()
+    {
+        lock (_lock)
+        {
+            return (_cache.Count, _maxSize);
+        }
+    }
+}
+
+/// <summary>
+/// Memory-efficient concurrent bag alternative
+/// </summary>
+public sealed class EfficientObjectPool<T> where T : class
+{
+    private readonly Stack<T> _stack;
+    private readonly Func<T> _factory;
+    private int _count;
+    private readonly int _maxSize;
+    private readonly object _lock = new();
+
+    public EfficientObjectPool(Func<T> factory, int maxSize = 100)
+    {
+        _factory = factory;
+        _maxSize = maxSize;
+        _stack = new Stack<T>(maxSize);
+    }
+
+    public T Rent()
+    {
+        lock (_lock)
+        {
+            return _stack.Count > 0 ? _stack.Pop() : _factory();
+        }
+    }
+
+    public void Return(T item)
+    {
+        if (item == null)
+        {
+            return;
+        }
+
+        lock (_lock)
+        {
+            if (_count < _maxSize)
+            {
+                _stack.Push(item);
+                _count++;
+            }
+        }
+    }
+
+    public int Count
+    {
+        get
+        {
+            lock (_lock)
+            {
+                return _count;
+            }
+        }
+    }
+
+    public void Clear()
+    {
+        lock (_lock)
+        {
+            _stack.Clear();
+            _count = 0;
+        }
+    }
+}

EonaCat.LogStack/EonaCatLoggerCore/MessageTemplate.cs

@@ -0,0 +1,690 @@
+using EonaCat.LogStack.Core;
+using System;
+using System.Collections.Generic;
+using System.Runtime.CompilerServices;
+using System.Text;
+
+namespace EonaCat.LogStack.Core;
+
+// This file is part of the EonaCat project(s) which is released under the Apache License.
+// See the LICENSE file or go to https://EonaCat.com/License for full license details.
+
+/// <summary>
+/// Hint for how a token's value should be captured.
+/// </summary>
+public enum TokenDestructureHint : byte
+{
+    /// <summary>ToString() / scalar value</summary>
+    Default = 0,
+    /// <summary>{@Property} — deep object destructuring (JSON-like)</summary>
+    Destructure = 1,
+    /// <summary>{$Property} — force ToString()</summary>
+    Stringify = 2
+}
+
+/// <summary>
+/// A single token parsed from a message template.
+/// Supports advanced features:
+/// - Nested property access: {Object.Property.SubProperty}
+/// - Array indexing: {Array[0]}
+/// - Alignment: {Name,10} (right), {Name,-10} (left)
+/// - Filters: {Name|uppercase}, {Name|truncate:20}
+/// - Conditionals: {?IsActive:Yes|No}
+/// - Fallback: {Name??'default'}
+/// </summary>
+public readonly struct TemplateToken
+{
+    /// <summary>True = literal text; False = property hole.</summary>
+    public readonly bool IsLiteral;
+    /// <summary>Literal text segment, or null for property holes.</summary>
+    public readonly string? Text;
+    /// <summary>Property name for holes (may be a digit for positional placeholders, supports dot notation).</summary>
+    public readonly string? Name;
+    /// <summary>Zero-based positional index for positional placeholders; -1 for named.</summary>
+    public readonly int Position;
+    /// <summary>Destructure / stringify hint.</summary>
+    public readonly TokenDestructureHint Hint;
+    /// <summary>Optional format string (e.g. "D2").</summary>
+    public readonly string? Format;
+    /// <summary>Alignment width (positive=right, negative=left).</summary>
+    public readonly int Alignment;
+    /// <summary>Applied filters (e.g., "uppercase", "truncate:10").</summary>
+    public readonly string[]? Filters;
+    /// <summary>Fallback value if property is null/missing.</summary>
+    public readonly string? Fallback;
+    /// <summary>Optional conditional true/false values for {?PropertyName:True|False}.</summary>
+    public readonly (string? TrueValue, string? FalseValue) ConditionalValues;
+
+    private TemplateToken(string literal)
+    {
+        IsLiteral = true;
+        Text = literal;
+        Name = null;
+        Position = -1;
+        Hint = TokenDestructureHint.Default;
+        Format = null;
+        Alignment = 0;
+        Filters = null;
+        Fallback = null;
+        ConditionalValues = (null, null);
+    }
+
+    private TemplateToken(string name, int position, TokenDestructureHint hint, string? format, int alignment = 0, string[]? filters = null, string? fallback = null, (string?, string?) conditionalValues = default)
+    {
+        IsLiteral = false;
+        Text = null;
+        Name = name;
+        Position = position;
+        Hint = hint;
+        Format = format;
+        Alignment = alignment;
+        Filters = filters;
+        Fallback = fallback;
+        ConditionalValues = conditionalValues;
+    }
+
+    public static TemplateToken Literal(string text) => new(text);
+
+    public static TemplateToken Property(string name, int position, TokenDestructureHint hint, string? format, int alignment = 0, string[]? filters = null, string? fallback = null, (string?, string?) conditionalValues = default)
+        => new(name, position, hint, format, alignment, filters, fallback, conditionalValues);
+
+    public override string ToString() =>
+        IsLiteral ? $"Literal({Text})" : $"Hole({Hint}{Name}{(Format != null ? ":" + Format : "")})";
+}
+
+/// <summary>
+/// Parses and renders Serilog-compatible message templates with advanced features.
+///
+/// Supported syntax:
+///   {PropertyName}              — named property (default destructure)
+///   {@PropertyName}             — named property, deep destructure
+///   {$PropertyName}             — named property, force-stringify
+///   {0}, {1}                    — positional
+///   {PropertyName:format}       — with format specifier (e.g., "D2", "C")
+///   {PropertyName,10}           — right-align with width 10
+///   {PropertyName,-10}          — left-align with width 10
+///   {Object.Property}           — nested property access (dot notation)
+///   {Array[0]}                  — array/collection indexing
+///   {PropertyName|uppercase}    — apply filter (uppercase, lowercase, truncate, etc.)
+///   {PropertyName??'default'}   — fallback value if null/missing
+///   {?IsActive:Yes|No}          — conditional rendering
+///   {{ }}                       — escaped braces → literal { }
+/// </summary>
+public sealed class MessageTemplate
+{
+    private readonly string _raw;
+    private readonly TemplateToken[] _tokens;
+
+    public string Raw => _raw;
+    public ReadOnlySpan<TemplateToken> Tokens => _tokens;
+
+    private MessageTemplate(string raw, TemplateToken[] tokens)
+    {
+        _raw = raw;
+        _tokens = tokens;
+    }
+
+    public static MessageTemplate Parse(string template)
+    {
+        if (template == null)
+        {
+            throw new ArgumentNullException(nameof(template));
+        }
+
+        var tokens = new List<TemplateToken>(8);
+        var sb = new StringBuilder(template.Length);
+        int i = 0;
+
+        while (i < template.Length)
+        {
+            char c = template[i];
+
+            if (c == '{')
+            {
+                // Escaped {{ → literal {
+                if (i + 1 < template.Length && template[i + 1] == '{')
+                {
+                    sb.Append('{');
+                    i += 2;
+                    continue;
+                }
+
+                // Flush accumulated literal
+                if (sb.Length > 0)
+                {
+                    tokens.Add(TemplateToken.Literal(sb.ToString()));
+                    sb.Clear();
+                }
+
+                // Find matching }
+                int end = FindClosingBrace(template, i + 1);
+                if (end < 0)
+                {
+                    // Unclosed brace → treat rest as literal
+                    sb.Append(template, i, template.Length - i);
+                    i = template.Length;
+                    continue;
+                }
+
+                string hole = template.Substring(i + 1, end - i - 1);
+                tokens.Add(ParseHole(hole));
+                i = end + 1;
+            }
+            else if (c == '}' && i + 1 < template.Length && template[i + 1] == '}')
+            {
+                // Escaped }}
+                sb.Append('}');
+                i += 2;
+            }
+            else
+            {
+                sb.Append(c);
+                i++;
+            }
+        }
+
+        if (sb.Length > 0)
+        {
+            tokens.Add(TemplateToken.Literal(sb.ToString()));
+        }
+
+        return new MessageTemplate(template, tokens.ToArray());
+    }
+
+    [MethodImpl(MethodImplOptions.AggressiveInlining)]
+    private static int FindClosingBrace(string template, int startPos)
+    {
+        for (int i = startPos; i < template.Length; i++)
+        {
+            if (template[i] == '}')
+            {
+                return i;
+            }
+        }
+        return -1;
+    }
+
+    [MethodImpl(MethodImplOptions.AggressiveInlining)]
+    private static TemplateToken ParseHole(string hole)
+    {
+        if (string.IsNullOrEmpty(hole))
+        {
+            return TemplateToken.Literal("{}");
+        }
+
+        var hint = TokenDestructureHint.Default;
+        int nameStart = 0;
+        bool isConditional = false;
+
+        // Check for conditional {?Property:True|False}
+        if (hole[0] == '?')
+        {
+            isConditional = true;
+            nameStart = 1;
+        }
+        else if (hole[0] == '@') { hint = TokenDestructureHint.Destructure; nameStart = 1; }
+        else if (hole[0] == '$') { hint = TokenDestructureHint.Stringify; nameStart = 1; }
+
+        // Extract components: name, alignment, format, filters, fallback, conditional
+        string name;
+        string? format = null;
+        int alignment = 0;
+        string[]? filters = null;
+        string? fallback = null;
+        (string?, string?) conditionalValues = (null, null);
+
+        // Parse: name[,alignment][|filters][??fallback][:format][:trueval|falseval]
+        string remaining = hole.Substring(nameStart);
+
+        // First, check for conditional values (only for conditional tokens)
+        if (isConditional && remaining.Contains(":"))
+        {
+            int colonIdx = remaining.IndexOf(':');
+            string beforeColon = remaining.Substring(0, colonIdx);
+            string afterColon = remaining.Substring(colonIdx + 1);
+
+            if (afterColon.Contains("|"))
+            {
+                int pipeIdx = afterColon.IndexOf('|');
+                conditionalValues.Item1 = afterColon.Substring(0, pipeIdx).Trim();
+                conditionalValues.Item2 = afterColon.Substring(pipeIdx + 1).Trim();
+                remaining = beforeColon;
+            }
+        }
+
+        // Parse filters (|uppercase, |truncate:10, etc.)
+        if (remaining.Contains("|"))
+        {
+            int pipeIdx = remaining.IndexOf('|');
+            string namePart = remaining.Substring(0, pipeIdx);
+            string filterPart = remaining.Substring(pipeIdx + 1);
+            remaining = namePart;
+            filters = filterPart.Split('|');
+        }
+
+        // Parse fallback (??'default')
+        if (remaining.Contains("??"))
+        {
+            int fallbackIdx = remaining.IndexOf("??");
+            string namePart = remaining.Substring(0, fallbackIdx);
+            fallback = remaining.Substring(fallbackIdx + 2).Trim();
+            if (fallback.StartsWith("'") && fallback.EndsWith("'"))
+            {
+                fallback = fallback.Substring(1, fallback.Length - 2);
+            }
+
+            remaining = namePart;
+        }
+
+        // Parse alignment (,10 or ,-10)
+        if (remaining.Contains(","))
+        {
+            int commaIdx = remaining.IndexOf(',');
+            string namePart = remaining.Substring(0, commaIdx);
+            string alignStr = remaining.Substring(commaIdx + 1).Trim();
+            if (int.TryParse(alignStr, out int align))
+            {
+                alignment = align;
+            }
+
+            remaining = namePart;
+        }
+
+        // Parse format (:D2, :C, etc.)
+        if (remaining.Contains(":") && !isConditional)
+        {
+            int colonIdx = remaining.IndexOf(':');
+            string namePart = remaining.Substring(0, colonIdx);
+            format = remaining.Substring(colonIdx + 1);
+            remaining = namePart;
+        }
+
+        name = remaining.Trim();
+
+        // Positional?
+        int position = -1;
+        if (name.Length > 0 && IsDigits(name))
+        {
+            int.TryParse(name, out position);
+        }
+
+        return TemplateToken.Property(name, position, hint, string.IsNullOrEmpty(format) ? null : format, alignment, filters, fallback, conditionalValues);
+    }
+
+    [MethodImpl(MethodImplOptions.AggressiveInlining)]
+    private static bool IsDigits(string s)
+    {
+        foreach (var c in s)
+        {
+            if (c < '0' || c > '9')
+            {
+                return false;
+            }
+        }
+
+        return true;
+    }
+
+    /// <summary>
+    /// Renders the template to a string, binding positional args and returning
+    /// a dictionary of named properties.
+    /// </summary>
+    public string Render(object?[]? args, out Dictionary<string, object?> properties)
+    {
+        properties = new Dictionary<string, object?>(StringComparer.Ordinal);
+        var sb = new StringBuilder(_raw.Length + 32);
+        int positionalIndex = 0;
+
+        foreach (ref readonly var token in _tokens.AsSpan())
+        {
+            if (token.IsLiteral)
+            {
+                sb.Append(token.Text);
+                continue;
+            }
+
+            object? value;
+
+            if (token.Position >= 0)
+            {
+                // Positional placeholder {0}, {1} …
+                value = (args != null && token.Position < args.Length) ? args[token.Position] : null;
+            }
+            else if (args != null && positionalIndex < args.Length && IsArgumentDriven(args))
+            {
+                value = args[positionalIndex++];
+                properties[token.Name!] = value;
+            }
+            else
+            {
+                value = ResolveNestedProperty(token.Name, properties);
+            }
+
+            if (token.Name != null && token.Position < 0)
+            {
+                properties[token.Name] = value;
+            }
+
+            AppendValue(sb, value, token.Hint, token.Format, token.Alignment, token.Filters, token.Fallback, token.ConditionalValues);
+        }
+
+        return sb.ToString();
+    }
+
+    /// <summary>
+    /// Resolves nested property access (e.g., "Object.Property.SubProperty")
+    /// </summary>
+    private static object? ResolveNestedProperty(string? propertyPath, Dictionary<string, object?> properties)
+    {
+        if (propertyPath == null)
+        {
+            return null;
+        }
+
+        // Check for array indexing: Array[0]
+        if (propertyPath.Contains("["))
+        {
+            int bracketIdx = propertyPath.IndexOf('[');
+            string baseName = propertyPath.Substring(0, bracketIdx);
+            string indexStr = propertyPath.Substring(bracketIdx + 1);
+            if (indexStr.EndsWith("]"))
+            {
+                indexStr = indexStr.Substring(0, indexStr.Length - 1);
+            }
+
+            if (properties.TryGetValue(baseName, out var collection))
+            {
+                return GetCollectionItem(collection, indexStr);
+            }
+            return null;
+        }
+
+        // Handle nested property access with dots
+        if (!propertyPath.Contains("."))
+        {
+            return properties.TryGetValue(propertyPath, out var val) ? val : null;
+        }
+
+        string[] parts = propertyPath.Split('.');
+        object? current = null;
+
+        if (!properties.TryGetValue(parts[0], out current))
+        {
+            return null;
+        }
+
+        for (int i = 1; i < parts.Length && current != null; i++)
+        {
+            current = GetPropertyValue(current, parts[i]);
+        }
+
+        return current;
+    }
+
+    private static object? GetPropertyValue(object? obj, string propertyName)
+    {
+        if (obj == null)
+        {
+            return null;
+        }
+
+        // Check for array indexing in nested path
+        if (propertyName.Contains("["))
+        {
+            int bracketIdx = propertyName.IndexOf('[');
+            string actualProp = propertyName.Substring(0, bracketIdx);
+            string indexStr = propertyName.Substring(bracketIdx + 1);
+            if (indexStr.EndsWith("]"))
+            {
+                indexStr = indexStr.Substring(0, indexStr.Length - 1);
+            }
+
+            var prop = obj.GetType().GetProperty(actualProp, System.Reflection.BindingFlags.IgnoreCase | System.Reflection.BindingFlags.Public | System.Reflection.BindingFlags.Instance);
+            if (prop?.CanRead == true)
+            {
+                var collection = prop.GetValue(obj);
+                return GetCollectionItem(collection, indexStr);
+            }
+            return null;
+        }
+
+        var propInfo = obj.GetType().GetProperty(propertyName, System.Reflection.BindingFlags.IgnoreCase | System.Reflection.BindingFlags.Public | System.Reflection.BindingFlags.Instance);
+        return propInfo?.CanRead == true ? propInfo.GetValue(obj) : null;
+    }
+
+    private static object? GetCollectionItem(object? collection, string indexStr)
+    {
+        if (collection == null)
+        {
+            return null;
+        }
+
+        try
+        {
+            if (collection is System.Collections.IList list && int.TryParse(indexStr, out int index))
+            {
+                return index >= 0 && index < list.Count ? list[index] : null;
+            }
+        }
+        catch { }
+
+        return null;
+    }
+
+    /// <summary>
+    /// Renders and populates the builder's properties from named holes.
+    /// </summary>
+    public string RenderInto(object?[]? args, LogEventBuilder builder)
+    {
+        var rendered = Render(args, out var props);
+        foreach (var kv in props)
+        {
+            builder.WithProperty(kv.Key, kv.Value);
+        }
+
+        return rendered;
+    }
+
+    [MethodImpl(MethodImplOptions.AggressiveInlining)]
+    private static void AppendValue(StringBuilder sb, object? value, TokenDestructureHint hint, string? format, int alignment, string[]? filters, string? fallback, (string?, string?) conditionalValues)
+    {
+        // Handle conditional rendering
+        if (conditionalValues.Item1 != null || conditionalValues.Item2 != null)
+        {
+            bool isTrue = IsTruthy(value);
+            sb.Append(isTrue ? conditionalValues.Item1 : conditionalValues.Item2);
+            return;
+        }
+
+        // Handle null/fallback
+        if (value == null)
+        {
+            sb.Append(fallback ?? "null");
+            return;
+        }
+
+        // Apply filters
+        if (filters != null && filters.Length > 0)
+        {
+            value = ApplyFilters(value, filters);
+        }
+
+        string formatted = FormatValue(value, hint, format);
+
+        // Apply alignment
+        if (alignment != 0)
+        {
+            formatted = alignment > 0
+                ? formatted.PadLeft(alignment)
+                : formatted.PadRight(-alignment);
+        }
+
+        sb.Append(formatted);
+    }
+
+    private static bool IsTruthy(object? value)
+    {
+        if (value == null)
+        {
+            return false;
+        }
+
+        if (value is bool b)
+        {
+            return b;
+        }
+
+        if (value is int i)
+        {
+            return i != 0;
+        }
+
+        if (value is long l)
+        {
+            return l != 0;
+        }
+
+        if (value is string s)
+        {
+            return !string.IsNullOrEmpty(s);
+        }
+
+        return true;
+    }
+
+    private static object? ApplyFilters(object? value, string[] filters)
+    {
+        if (value == null)
+        {
+            return null;
+        }
+
+        foreach (var filter in filters)
+        {
+            string filterName = filter;
+            string? filterParam = null;
+
+            if (filter.Contains(":", StringComparison.Ordinal))
+            {
+                int colonIdx = filter.IndexOf(':');
+                filterName = filter.Substring(0, colonIdx).Trim();
+                filterParam = filter.Substring(colonIdx + 1).Trim();
+            }
+
+            value = ApplyFilter(value, filterName, filterParam);
+        }
+
+        return value;
+    }
+
+    private static object? ApplyFilter(object? value, string filterName, string? param)
+    {
+        if (value == null)
+        {
+            return null;
+        }
+
+        string str = value.ToString() ?? "";
+
+        if (filterName.Equals("reverse", StringComparison.OrdinalIgnoreCase))
+        {
+            var chars = str.ToCharArray();
+            System.Array.Reverse(chars);
+            return new string(chars);
+        }
+
+        return filterName.ToLowerInvariant() switch
+        {
+            "uppercase" or "upper" => str.ToUpperInvariant(),
+            "lowercase" or "lower" => str.ToLowerInvariant(),
+            "trim" => str.Trim(),
+            "truncate" => param != null && int.TryParse(param, out int len) ? (str.Length > len ? str.Substring(0, len) + "…" : str) : str,
+            "substr" or "substring" => param != null && int.TryParse(param, out int pos) && pos < str.Length ? str.Substring(pos) : str,
+            _ => str
+        };
+    }
+
+    private static string FormatValue(object value, TokenDestructureHint hint, string? format)
+    {
+        if (hint == TokenDestructureHint.Destructure)
+        {
+            return Destructure(value);
+        }
+
+        if (value is IFormattable formattable && format != null)
+        {
+            try
+            {
+                return formattable.ToString(format, System.Globalization.CultureInfo.InvariantCulture);
+            }
+            catch
+            {
+                return value.ToString() ?? "";
+            }
+        }
+
+        return value.ToString() ?? "";
+    }
+
+    private static string Destructure(object obj)
+    {
+        if (obj == null)
+        {
+            return "null";
+        }
+
+        var t = obj.GetType();
+        if (t.IsPrimitive || obj is string || obj is decimal || obj is DateTime || obj is DateTimeOffset || obj is Guid)
+        {
+            return obj.ToString()!;
+        }
+
+        // Deep property bag with nesting
+        var sb = new StringBuilder("{");
+        bool first = true;
+        foreach (var prop in t.GetProperties(System.Reflection.BindingFlags.Public | System.Reflection.BindingFlags.Instance))
+        {
+            try
+            {
+                if (!first)
+                {
+                    sb.Append(", ");
+                }
+
+                var val = prop.GetValue(obj);
+                sb.Append(prop.Name).Append(": ");
+                if (val == null)
+                {
+                    sb.Append("null");
+                }
+                else if (val.GetType().IsPrimitive || val is string || val is decimal || val is DateTime || val is DateTimeOffset)
+                {
+                    sb.Append(val);
+                }
+                else
+                {
+                    sb.Append(Destructure(val));
+                }
+
+                first = false;
+            }
+            catch { }
+        }
+        sb.Append('}');
+        return sb.ToString();
+    }
+
+    [MethodImpl(MethodImplOptions.AggressiveInlining)]
+    private static bool IsArgumentDriven(object?[] args) => args.Length > 0;
+
+    // Template cache to avoid re-parsing the same strings
+    private static readonly System.Collections.Concurrent.ConcurrentDictionary<string, MessageTemplate> _cache
+        = new(StringComparer.Ordinal);
+
+    /// <summary>Returns a cached parsed template (recommended for hot paths).</summary>
+    public static MessageTemplate FromCache(string template) =>
+        _cache.GetOrAdd(template, static t => Parse(t));
+
+    /// <summary>Clears the template parse cache.</summary>
+    public static void ClearCache() => _cache.Clear();
+}

EonaCat.LogStack/EonaCatLoggerCore/Policies/PolicyEngine.cs

@@ -0,0 +1,371 @@
+using EonaCat.LogStack.Core;
+using EonaCat.LogStack.Flows;
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Threading.Tasks;
+
+namespace EonaCat.LogStack.Policies;
+
+// This file is part of the EonaCat project(s) which is released under the Apache License.
+// See the LICENSE file or go to https://EonaCat.com/License for full license details.
+
+/// <summary>
+/// Represents a routing rule that determines which flows should handle an event
+/// </summary>
+public class RoutingRule
+{
+    public string Name { get; set; } = "";
+    public int Priority { get; set; }
+    public Func<LogEvent, bool> Condition { get; set; } = _ => true;
+    public List<string> TargetFlows { get; set; } = new();
+    public bool IsActive { get; set; } = true;
+}
+
+/// <summary>
+/// Policy engine that manages conditional routing and flow selection
+/// </summary>
+public sealed class PolicyEngine
+{
+    private readonly List<RoutingRule> _rules = new();
+    private readonly Dictionary<string, IFlow> _flowRegistry = new();
+    private readonly object _lock = new object();
+
+    public PolicyEngine() { }
+
+    /// <summary>
+    /// Registers a flow by name
+    /// </summary>
+    public void RegisterFlow(string name, IFlow flow)
+    {
+        if (string.IsNullOrEmpty(name))
+        {
+            throw new ArgumentNullException(nameof(name));
+        }
+
+        lock (_lock)
+        {
+            _flowRegistry[name] = flow ?? throw new ArgumentNullException(nameof(flow));
+        }
+    }
+
+    /// <summary>
+    /// Unregisters a flow
+    /// </summary>
+    public void UnregisterFlow(string name)
+    {
+        lock (_lock)
+        {
+            _flowRegistry.Remove(name);
+        }
+    }
+
+    /// <summary>
+    /// Adds a routing rule
+    /// </summary>
+    public PolicyEngine AddRule(RoutingRule rule)
+    {
+        if (rule == null)
+        {
+            throw new ArgumentNullException(nameof(rule));
+        }
+
+        lock (_lock)
+        {
+            _rules.Add(rule);
+            _rules.Sort((a, b) => b.Priority.CompareTo(a.Priority));
+        }
+
+        return this;
+    }
+
+    /// <summary>
+    /// Creates and adds a conditional routing rule
+    /// </summary>
+    public PolicyEngine AddConditionalRule(
+        string name,
+        Func<LogEvent, bool> condition,
+        List<string> targetFlows,
+        int priority = 0)
+    {
+        var rule = new RoutingRule
+        {
+            Name = name,
+            Condition = condition,
+            TargetFlows = targetFlows,
+            Priority = priority,
+            IsActive = true
+        };
+
+        return AddRule(rule);
+    }
+
+    /// <summary>
+    /// Creates a rule that routes errors to specific flows
+    /// </summary>
+    public PolicyEngine AddErrorRoute(List<string> targetFlows, int priority = 10)
+    {
+        return AddConditionalRule(
+            "ErrorRoute",
+            e => e.Level >= LogLevel.Error,
+            targetFlows,
+            priority);
+    }
+
+    /// <summary>
+    /// Creates a rule that routes events from a specific category
+    /// </summary>
+    public PolicyEngine AddCategoryRoute(string category, List<string> targetFlows, int priority = 5)
+    {
+        return AddConditionalRule(
+            $"Category:{category}",
+            e => e.Category == category,
+            targetFlows,
+            priority);
+    }
+
+    /// <summary>
+    /// Gets the flows that should handle a given event
+    /// </summary>
+    public List<IFlow> GetTargetFlows(LogEvent logEvent)
+    {
+        lock (_lock)
+        {
+            var targetFlows = new List<IFlow>();
+
+            foreach (var rule in _rules)
+            {
+                if (!rule.IsActive)
+                {
+                    continue;
+                }
+
+                if (rule.Condition(logEvent))
+                {
+                    foreach (var flowName in rule.TargetFlows)
+                    {
+                        if (_flowRegistry.TryGetValue(flowName, out var flow))
+                        {
+                            targetFlows.Add(flow);
+                        }
+                    }
+                    break; // First matching rule wins
+                }
+            }
+
+            return targetFlows.Count > 0 ? targetFlows : new List<IFlow>(_flowRegistry.Values);
+        }
+    }
+
+    /// <summary>
+    /// Enables/disables a rule by name
+    /// </summary>
+    public void SetRuleActive(string ruleName, bool active)
+    {
+        lock (_lock)
+        {
+            var rule = _rules.FirstOrDefault(r => r.Name == ruleName);
+            if (rule != null)
+            {
+                rule.IsActive = active;
+            }
+        }
+    }
+
+    /// <summary>
+    /// Gets all registered flows
+    /// </summary>
+    public Dictionary<string, IFlow> GetAllFlows()
+    {
+        lock (_lock)
+        {
+            return new Dictionary<string, IFlow>(_flowRegistry);
+        }
+    }
+
+    /// <summary>
+    /// Gets all routing rules
+    /// </summary>
+    public List<RoutingRule> GetRules()
+    {
+        lock (_lock)
+        {
+            return new List<RoutingRule>(_rules);
+        }
+    }
+
+    /// <summary>
+    /// Clears all rules
+    /// </summary>
+    public void ClearRules()
+    {
+        lock (_lock)
+        {
+            _rules.Clear();
+        }
+    }
+
+    /// <summary>
+    /// Gets diagnostics about policies
+    /// </summary>
+    public PolicyDiagnostics GetDiagnostics()
+    {
+        lock (_lock)
+        {
+            return new PolicyDiagnostics
+            {
+                TotalRules = _rules.Count,
+                ActiveRules = _rules.Count(r => r.IsActive),
+                RegisteredFlows = _flowRegistry.Count
+            };
+        }
+    }
+}
+
+/// <summary>
+/// Diagnostics about policy engine state
+/// </summary>
+public class PolicyDiagnostics
+{
+    public int TotalRules { get; set; }
+    public int ActiveRules { get; set; }
+    public int RegisteredFlows { get; set; }
+}
+
+/// <summary>
+/// Quota management for rate limiting across categories
+/// </summary>
+public sealed class QuotaManager
+{
+    private class QuotaEntry
+    {
+        public int AllowedPerSecond { get; set; }
+        public DateTime WindowStart { get; set; } = DateTime.UtcNow;
+        public int CurrentCount { get; set; }
+    }
+
+    private readonly Dictionary<string, QuotaEntry> _quotas = new();
+    private readonly object _lock = new object();
+
+    /// <summary>
+    /// Sets the quota for a category
+    /// </summary>
+    public void SetQuota(string category, int eventsPerSecond)
+    {
+        if (eventsPerSecond <= 0)
+        {
+            throw new ArgumentOutOfRangeException(nameof(eventsPerSecond));
+        }
+
+        lock (_lock)
+        {
+            _quotas[category] = new QuotaEntry { AllowedPerSecond = eventsPerSecond };
+        }
+    }
+
+    /// <summary>
+    /// Checks if an event should be allowed based on quota
+    /// </summary>
+    public bool IsAllowed(string category)
+    {
+        lock (_lock)
+        {
+            if (!_quotas.TryGetValue(category, out var quota))
+            {
+                return true; // No quota = unlimited
+            }
+
+            var now = DateTime.UtcNow;
+            if ((now - quota.WindowStart).TotalSeconds >= 1.0)
+            {
+                // New window
+                quota.WindowStart = now;
+                quota.CurrentCount = 0;
+            }
+
+            if (quota.CurrentCount < quota.AllowedPerSecond)
+            {
+                quota.CurrentCount++;
+                return true;
+            }
+
+            return false;
+        }
+    }
+
+    /// <summary>
+    /// Gets usage statistics for all quotas
+    /// </summary>
+    public Dictionary<string, (int allowed, int used)> GetStatistics()
+    {
+        lock (_lock)
+        {
+            return _quotas.ToDictionary(
+                kvp => kvp.Key,
+                kvp => (kvp.Value.AllowedPerSecond, kvp.Value.CurrentCount));
+        }
+    }
+
+    /// <summary>
+    /// Resets all quotas
+    /// </summary>
+    public void Reset()
+    {
+        lock (_lock)
+        {
+            foreach (var quota in _quotas.Values)
+            {
+                quota.CurrentCount = 0;
+                quota.WindowStart = DateTime.UtcNow;
+            }
+        }
+    }
+
+    /// <summary>
+    /// Clears all quota entries
+    /// </summary>
+    public void Clear()
+    {
+        lock (_lock)
+        {
+            _quotas.Clear();
+        }
+    }
+}
+
+/// <summary>
+/// Extension methods for policy management
+/// </summary>
+public static class PolicyExtensions
+{
+    /// <summary>
+    /// Adds a default error flow route
+    /// </summary>
+    public static PolicyEngine AddDefaultErrorHandling(
+        this PolicyEngine engine,
+        string errorFlowName)
+    {
+        return engine.AddErrorRoute(new List<string> { errorFlowName });
+    }
+
+    /// <summary>
+    /// Creates a policy engine with common patterns
+    /// </summary>
+    public static PolicyEngine CreateStandardEngine(
+        IFlow consoleFlow,
+        IFlow fileFlow,
+        IFlow? errorFileFlow = null)
+    {
+        var engine = new PolicyEngine();
+        engine.RegisterFlow("console", consoleFlow);
+        engine.RegisterFlow("file", fileFlow);
+
+        if (errorFileFlow != null)
+        {
+            engine.RegisterFlow("error", errorFileFlow);
+            engine.AddErrorRoute(new List<string> { "error", "console" }, priority: 10);
+        }
+
+        return engine;
+    }
+}

EonaCat.LogStack/EonaCatLoggerCore/Pooling/BufferPool.cs

@@ -0,0 +1,153 @@
+using System;
+using System.Buffers;
+using System.Collections.Concurrent;
+using System.Threading;
+
+namespace EonaCat.LogStack.Pooling;
+
+// This file is part of the EonaCat project(s) which is released under the Apache License.
+// See the LICENSE file or go to https://EonaCat.com/License for full license details.
+
+/// <summary>
+/// High-performance buffer pool using ArrayPool for optimal memory efficiency.
+/// Manages buffers across multiple size tiers for flexible allocation patterns.
+/// </summary>
+public sealed class BufferPool : IDisposable
+{
+    private readonly int[] _standardSizes = { 512, 1024, 4096, 8192, 16384, 65536 };
+    private readonly ConcurrentDictionary<int, ArrayPool<byte>> _pools;
+    private bool _isDisposed;
+
+    public BufferPool()
+    {
+        _pools = new ConcurrentDictionary<int, ArrayPool<byte>>();
+        foreach (var size in _standardSizes)
+        {
+            _pools[size] = ArrayPool<byte>.Shared;
+        }
+    }
+
+    /// <summary>
+    /// Rents a buffer of at least the specified length
+    /// </summary>
+    public byte[] Rent(int minimumLength)
+    {
+        if (_isDisposed)
+        {
+            throw new ObjectDisposedException(nameof(BufferPool));
+        }
+
+        // Find the smallest standard size that fits
+        int selectedSize = minimumLength;
+        foreach (var size in _standardSizes)
+        {
+            if (size >= minimumLength)
+            {
+                selectedSize = size;
+                break;
+            }
+        }
+
+        return ArrayPool<byte>.Shared.Rent(selectedSize);
+    }
+
+    /// <summary>
+    /// Returns a buffer to the pool
+    /// </summary>
+    public void Return(byte[] buffer, bool clearBuffer = false)
+    {
+        if (_isDisposed || buffer == null)
+        {
+            return;
+        }
+
+        ArrayPool<byte>.Shared.Return(buffer, clearBuffer);
+    }
+
+    /// <summary>
+    /// Gets statistics about pool usage
+    /// </summary>
+    public ArrayPoolStatistics GetStatistics()
+    {
+        return new ArrayPoolStatistics
+        {
+            TotalAllocations = ArrayPool<byte>.Shared.GetTotalAllocations(),
+            BytesAllocated = ArrayPool<byte>.Shared.GetTotalBytesAllocated()
+        };
+    }
+
+    public void Dispose()
+    {
+        if (_isDisposed)
+        {
+            return;
+        }
+
+        _isDisposed = true;
+        // ArrayPool.Shared is static and managed by runtime
+    }
+}
+
+/// <summary>
+/// Statistics about array pool usage
+/// </summary>
+public class ArrayPoolStatistics
+{
+    public long TotalAllocations { get; set; }
+    public long BytesAllocated { get; set; }
+}
+
+/// <summary>
+/// Rented buffer that automatically returns itself to the pool when disposed
+/// </summary>
+public sealed class RentedBuffer : IDisposable
+{
+    private byte[] _buffer;
+    private readonly int _actualLength;
+    private readonly BufferPool? _pool;
+
+    public RentedBuffer(BufferPool? pool, int minimumLength)
+    {
+        _pool = pool;
+        _buffer = pool?.Rent(minimumLength) ?? new byte[minimumLength];
+        _actualLength = minimumLength;
+    }
+
+    public byte[] Buffer => _buffer;
+    public Span<byte> AsSpan() => new Span<byte>(_buffer, 0, _actualLength);
+    public Memory<byte> AsMemory() => new Memory<byte>(_buffer, 0, _actualLength);
+
+    public void Dispose()
+    {
+        if (_buffer != null)
+        {
+            _pool?.Return(_buffer, clearBuffer: true);
+            _buffer = null!;
+        }
+    }
+}
+
+/// <summary>
+/// Extension methods for ArrayPool integration
+/// </summary>
+public static class ArrayPoolExtensions
+{
+    /// <summary>
+    /// Gets total allocations from the shared ArrayPool (via reflection/diagnostics)
+    /// </summary>
+    public static long GetTotalAllocations(this ArrayPool<byte> pool)
+    {
+        // This is a placeholder - actual statistics would require reflection or instrumentation
+        // For now, this provides a hook for future diagnostics integration
+        return 0;
+    }
+
+    /// <summary>
+    /// Gets total bytes allocated from the shared ArrayPool
+    /// </summary>
+    public static long GetTotalBytesAllocated(this ArrayPool<byte> pool)
+    {
+        // This is a placeholder for diagnostics integration
+        return 0;
+    }
+}

EonaCat.LogStack/EonaCatLoggerCore/Pooling/ObjectPool.cs

@@ -0,0 +1,122 @@
+using System;
+using System.Collections.Concurrent;
+using System.Threading;
+
+namespace EonaCat.LogStack.Pooling;
+
+// This file is part of the EonaCat project(s) which is released under the Apache License.
+// See the LICENSE file or go to https://EonaCat.com/License for full license details.
+
+/// <summary>
+/// High-performance object pool for reusing expensive objects without external dependencies.
+/// Supports automatic cleanup and size limiting.
+/// </summary>
+public sealed class ObjectPool<T> : IDisposable where T : class
+{
+    private readonly ConcurrentBag<T> _pool;
+    private readonly Func<T> _factory;
+    private readonly Action<T>? _resetAction;
+    private readonly int _maxSize;
+    private int _currentCount;
+    private bool _isDisposed;
+
+    public ObjectPool(Func<T> factory, Action<T>? resetAction = null, int maxSize = 100)
+    {
+        _factory = factory ?? throw new ArgumentNullException(nameof(factory));
+        _resetAction = resetAction;
+        _maxSize = maxSize;
+        _pool = new ConcurrentBag<T>();
+        _currentCount = 0;
+    }
+
+    /// <summary>
+    /// Rents an object from the pool, creating a new one if necessary
+    /// </summary>
+    public T Rent()
+    {
+        if (_isDisposed)
+        {
+            throw new ObjectDisposedException(nameof(ObjectPool<T>));
+        }
+
+        if (_pool.TryTake(out var item))
+        {
+            Interlocked.Decrement(ref _currentCount);
+            return item;
+        }
+
+        return _factory();
+    }
+
+    /// <summary>
+    /// Returns an object to the pool after optional reset
+    /// </summary>
+    public void Return(T item)
+    {
+        if (_isDisposed || item == null)
+        {
+            return;
+        }
+
+        if (Interlocked.Increment(ref _currentCount) <= _maxSize)
+        {
+            _resetAction?.Invoke(item);
+            _pool.Add(item);
+        }
+        else
+        {
+            Interlocked.Decrement(ref _currentCount);
+            (item as IDisposable)?.Dispose();
+        }
+    }
+
+    /// <summary>
+    /// Gets the current number of pooled objects
+    /// </summary>
+    public int PooledCount => _currentCount;
+
+    /// <summary>
+    /// Clears all pooled objects
+    /// </summary>
+    public void Clear()
+    {
+        while (_pool.TryTake(out var item))
+        {
+            (item as IDisposable)?.Dispose();
+            Interlocked.Decrement(ref _currentCount);
+        }
+    }
+
+    public void Dispose()
+    {
+        if (_isDisposed)
+        {
+            return;
+        }
+
+        _isDisposed = true;
+        Clear();
+    }
+}
+
+/// <summary>
+/// Pooled object wrapper that returns itself to the pool when disposed
+/// </summary>
+public sealed class PooledObject<T> : IDisposable where T : class
+{
+    private readonly ObjectPool<T> _pool;
+    private readonly T _item;
+
+    public PooledObject(ObjectPool<T> pool)
+    {
+        _pool = pool ?? throw new ArgumentNullException(nameof(pool));
+        _item = pool.Rent();
+    }
+
+    public T Item => _item;
+
+    public void Dispose()
+    {
+        _pool.Return(_item);
+    }
+}

EonaCat.LogStack/EonaCatLoggerCore/Pooling/StringBuilderPool.cs

@@ -0,0 +1,210 @@
+using System;
+using System.Text;
+using System.Collections.Concurrent;
+using System.Threading;
+
+namespace EonaCat.LogStack.Pooling;
+
+// This file is part of the EonaCat project(s) which is released under the Apache License.
+// See the LICENSE file or go to https://EonaCat.com/License for full license details.
+
+/// <summary>
+/// High-performance StringBuilder pool with automatic capacity management.
+/// Reuses StringBuilders to reduce GC pressure in high-throughput scenarios.
+/// </summary>
+public sealed class StringBuilderPool : IDisposable
+{
+    private readonly ConcurrentBag<StringBuilder> _smallPool;   // <= 1KB
+    private readonly ConcurrentBag<StringBuilder> _mediumPool;  // 1KB - 8KB
+    private readonly ConcurrentBag<StringBuilder> _largePool;   // > 8KB
+
+    private const int SmallCapacity = 1024;
+    private const int MediumCapacity = 8192;
+    private const int SmallPoolLimit = 20;
+    private const int MediumPoolLimit = 10;
+    private const int LargePoolLimit = 5;
+
+    private int _smallCount;
+    private int _mediumCount;
+    private int _largeCount;
+    private bool _isDisposed;
+
+    public StringBuilderPool()
+    {
+        _smallPool = new ConcurrentBag<StringBuilder>();
+        _mediumPool = new ConcurrentBag<StringBuilder>();
+        _largePool = new ConcurrentBag<StringBuilder>();
+    }
+
+    /// <summary>
+    /// Rents a StringBuilder from the appropriate pool based on requested capacity
+    /// </summary>
+    public StringBuilder Rent(int capacity = 1024)
+    {
+        if (_isDisposed)
+        {
+            throw new ObjectDisposedException(nameof(StringBuilderPool));
+        }
+
+        ConcurrentBag<StringBuilder>? pool;
+        int currentCount;
+
+        if (capacity <= SmallCapacity)
+        {
+            pool = _smallPool;
+            currentCount = _smallCount;
+        }
+        else if (capacity <= MediumCapacity)
+        {
+            pool = _mediumPool;
+            currentCount = _mediumCount;
+        }
+        else
+        {
+            pool = _largePool;
+            currentCount = _largeCount;
+        }
+
+        if (currentCount > 0 && pool.TryTake(out var sb))
+        {
+            if (capacity <= SmallCapacity)
+            {
+                Interlocked.Decrement(ref _smallCount);
+            }
+            else if (capacity <= MediumCapacity)
+            {
+                Interlocked.Decrement(ref _mediumCount);
+            }
+            else
+            {
+                Interlocked.Decrement(ref _largeCount);
+            }
+
+            sb.Clear();
+            return sb;
+        }
+
+        return new StringBuilder(capacity);
+    }
+
+    public void Return(StringBuilder sb)
+    {
+        if (_isDisposed || sb == null)
+        {
+            return;
+        }
+
+        int capacity = sb.Capacity;
+        ConcurrentBag<StringBuilder>? pool;
+        int maxLimit;
+
+        if (capacity <= SmallCapacity)
+        {
+            pool = _smallPool;
+            maxLimit = SmallPoolLimit;
+            if (Interlocked.Increment(ref _smallCount) <= maxLimit)
+            {
+                sb.Clear();
+                pool.Add(sb);
+            }
+            else
+            {
+                Interlocked.Decrement(ref _smallCount);
+            }
+        }
+        else if (capacity <= MediumCapacity)
+        {
+            pool = _mediumPool;
+            maxLimit = MediumPoolLimit;
+            if (Interlocked.Increment(ref _mediumCount) <= maxLimit)
+            {
+                sb.Clear();
+                pool.Add(sb);
+            }
+            else
+            {
+                Interlocked.Decrement(ref _mediumCount);
+            }
+        }
+        else
+        {
+            pool = _largePool;
+            maxLimit = LargePoolLimit;
+            if (Interlocked.Increment(ref _largeCount) <= maxLimit)
+            {
+                sb.Clear();
+                pool.Add(sb);
+            }
+            else
+            {
+                Interlocked.Decrement(ref _largeCount);
+            }
+        }
+    }
+
+    /// <summary>
+    /// Gets pooled item counts for diagnostics
+    /// </summary>
+    public (int small, int medium, int large) GetPoolCounts()
+        => (_smallCount, _mediumCount, _largeCount);
+
+    /// <summary>
+    /// Clears all pools
+    /// </summary>
+    public void Clear()
+    {
+        while (_smallPool.TryTake(out _))
+        {
+            ;
+        }
+
+        while (_mediumPool.TryTake(out _))
+        {
+            ;
+        }
+
+        while (_largePool.TryTake(out _))
+        {
+            ;
+        }
+
+        _smallCount = 0;
+        _mediumCount = 0;
+        _largeCount = 0;
+    }
+
+    public void Dispose()
+    {
+        if (_isDisposed)
+        {
+            return;
+        }
+
+        _isDisposed = true;
+        Clear();
+    }
+}
+
+/// <summary>
+/// Rented StringBuilder that automatically returns itself to the pool when disposed
+/// </summary>
+public sealed class PooledStringBuilder : IDisposable
+{
+    private readonly StringBuilderPool _pool;
+    private readonly StringBuilder _sb;
+
+    public PooledStringBuilder(StringBuilderPool pool, int capacity = 1024)
+    {
+        _pool = pool ?? throw new ArgumentNullException(nameof(pool));
+        _sb = pool.Rent(capacity);
+    }
+
+    public StringBuilder Builder => _sb;
+
+    public override string ToString() => _sb.ToString();
+
+    public void Dispose()
+    {
+        _pool.Return(_sb);
+    }
+}

EonaCat.LogStack/EonaCatLoggerCore/Structured/StructuredProperties.cs

@@ -0,0 +1,214 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Threading;
+
+namespace EonaCat.LogStack.Structured;
+
+// This file is part of the EonaCat project(s) which is released under the Apache License.
+// See the LICENSE file or go to https://EonaCat.com/License for full license details.
+
+/// <summary>
+/// Represents a structured property with type information
+/// </summary>
+public sealed class StructuredProperty
+{
+    public string Name { get; set; }
+    public object? Value { get; set; }
+    public Type? ValueType { get; set; }
+    public bool ShouldDestructure { get; set; }
+
+    public StructuredProperty(string name, object? value, bool shouldDestructure = false)
+    {
+        Name = name;
+        Value = value;
+        ValueType = value?.GetType();
+        ShouldDestructure = shouldDestructure;
+    }
+}
+
+/// <summary>
+/// Builder for structured properties using Serilog-like syntax
+/// </summary>
+public sealed class StructuredPropertyBuilder
+{
+    private readonly Dictionary<string, StructuredProperty> _properties = new();
+
+    /// <summary>
+    /// Adds a simple property
+    /// </summary>
+    public StructuredPropertyBuilder Add(string name, object? value)
+    {
+        _properties[name] = new StructuredProperty(name, value, false);
+        return this;
+    }
+
+    /// <summary>
+    /// Adds a property that should be destructured (rendered as JSON)
+    /// </summary>
+    public StructuredPropertyBuilder AddDestructured(string name, object? value)
+    {
+        _properties[name] = new StructuredProperty(name, value, true);
+        return this;
+    }
+
+    /// <summary>
+    /// Adds multiple properties from an anonymous object
+    /// Example: .AddFromAnonymous(new { UserId = 123, Action = "Login" })
+    /// </summary>
+    public StructuredPropertyBuilder AddFromAnonymous(object anonymous)
+    {
+        if (anonymous == null)
+        {
+            return this;
+        }
+
+        var properties = anonymous.GetType().GetProperties();
+        foreach (var prop in properties)
+        {
+            try
+            {
+                var value = prop.GetValue(anonymous);
+                Add(prop.Name, value);
+            }
+            catch
+            {
+                // Ignore properties that can't be read
+            }
+        }
+
+        return this;
+    }
+
+    /// <summary>
+    /// Adds multiple properties from a dictionary
+    /// </summary>
+    public StructuredPropertyBuilder AddFromDictionary(Dictionary<string, object?> dict)
+    {
+        if (dict == null)
+        {
+            return this;
+        }
+
+        foreach (var kvp in dict)
+        {
+            Add(kvp.Key, kvp.Value);
+        }
+
+        return this;
+    }
+
+    /// <summary>
+    /// Removes a property
+    /// </summary>
+    public StructuredPropertyBuilder Remove(string name)
+    {
+        _properties.Remove(name);
+        return this;
+    }
+
+    /// <summary>
+    /// Clears all properties
+    /// </summary>
+    public StructuredPropertyBuilder Clear()
+    {
+        _properties.Clear();
+        return this;
+    }
+
+    /// <summary>
+    /// Gets the built dictionary
+    /// </summary>
+    public Dictionary<string, object?> Build()
+    {
+        return _properties.ToDictionary(kvp => kvp.Key, kvp => kvp.Value.Value);
+    }
+
+    /// <summary>
+    /// Gets the structured properties
+    /// </summary>
+    public Dictionary<string, StructuredProperty> BuildStructured()
+    {
+        return new Dictionary<string, StructuredProperty>(_properties);
+    }
+
+    /// <summary>
+    /// Gets count of properties
+    /// </summary>
+    public int Count => _properties.Count;
+}
+
+/// <summary>
+/// Contextual property scope that inherits to nested calls
+/// Similar to Serilog's LogContext.PushProperty
+/// </summary>
+public sealed class PropertyScope : IDisposable
+{
+    private readonly Stack<Dictionary<string, object?>> _scopeStack;
+    private readonly Dictionary<string, object?> _currentScope;
+
+    private static readonly AsyncLocal<PropertyScope?> _currentScopeHolder = new();
+
+    public PropertyScope(Dictionary<string, object?> initialProperties)
+    {
+        _scopeStack = new Stack<Dictionary<string, object?>>();
+        _currentScope = new Dictionary<string, object?>(initialProperties);
+        _scopeStack.Push(_currentScope);
+
+        var previous = _currentScopeHolder.Value;
+        _currentScopeHolder.Value = this;
+    }
+
+    public void PushScope(Dictionary<string, object?> properties)
+    {
+        var newScope = new Dictionary<string, object?>(_scopeStack.Peek());
+        foreach (var kvp in properties)
+        {
+            newScope[kvp.Key] = kvp.Value;
+        }
+        _scopeStack.Push(newScope);
+    }
+
+    public void PopScope()
+    {
+        if (_scopeStack.Count > 1)
+        {
+            _scopeStack.Pop();
+        }
+    }
+
+    public Dictionary<string, object?> GetCurrentProperties()
+    {
+        if (_scopeStack.Count == 0)
+        {
+            return new Dictionary<string, object?>();
+        }
+
+        return new Dictionary<string, object?>(_scopeStack.Peek());
+    }
+
+    public static Dictionary<string, object?> GetActiveProperties()
+    {
+        var scope = _currentScopeHolder.Value;
+        return scope?.GetCurrentProperties() ?? new Dictionary<string, object?>();
+    }
+
+    public void Dispose()
+    {
+        _scopeStack.Clear();
+        if (_currentScopeHolder.Value == this)
+        {
+            _currentScopeHolder.Value = null;
+        }
+    }
+}
+
+/// <summary>
+/// Extensions for adding properties to LogEvent
+/// </summary>
+public static class StructuredPropertyExtensions
+{
+    // Note: These extension methods are intended to extend LogEventBuilder
+    // from EonaCat.LogStack.Core once that type is available.
+    // For now, they are provided as examples for integration patterns.
+}

EonaCat.LogStack/Extensions/HostApplicationBuilderExtensions.cs

@@ -1,14 +1,125 @@
+using EonaCat.LogStack.Configuration;
 using EonaCat.LogStack.Core;
+using EonaCat.LogStack.Logging;
 using Microsoft.Extensions.Hosting;
 using System;
 
 namespace EonaCat.LogStack.Extensions;
 
+/// <summary>
+/// Extension methods for integrating EonaCat LogStack with HostApplicationBuilder
+/// </summary>
 public static class HostApplicationBuilderExtensions
 {
-    public static IHostApplicationBuilder AddEonaCatLogging(this IHostApplicationBuilder builder, Action<EonaCatLogStack>? configure=null)
+    /// <summary>
+    /// Adds EonaCat LogStack logging with a configuration callback
+    /// </summary>
+    public static IHostApplicationBuilder AddEonaCatLogging(
+        this IHostApplicationBuilder builder, 
+        Action<EonaCatLogStack>? configure = null)
     {
+        if (builder == null)
+        {
+            throw new ArgumentNullException(nameof(builder));
+        }
+
         builder.Services.AddEonaCatLogging(configure ?? (_ => { }));
         return builder;
     }
+
+    /// <summary>
+    /// Adds EonaCat LogStack logging with fluent LogBuilder configuration
+    /// </summary>
+    public static IHostApplicationBuilder AddEonaCatLogging(
+        this IHostApplicationBuilder builder,
+        Action<LogBuilder> configure)
+    {
+        if (builder == null)
+        {
+            throw new ArgumentNullException(nameof(builder));
+        }
+
+        if (configure == null)
+        {
+            throw new ArgumentNullException(nameof(configure));
+        }
+
+        builder.Services.AddEonaCatLogging(configure);
+        return builder;
+    }
+
+    /// <summary>
+    /// Adds EonaCat LogStack logging with fluent LogBuilder configuration and a specific category
+    /// </summary>
+    public static IHostApplicationBuilder AddEonaCatLogging(
+        this IHostApplicationBuilder builder,
+        string category,
+        Action<LogBuilder> configure)
+    {
+        if (builder == null)
+        {
+            throw new ArgumentNullException(nameof(builder));
+        }
+
+        if (configure == null)
+        {
+            throw new ArgumentNullException(nameof(configure));
+        }
+
+        builder.Services.AddEonaCatLogging(category, configure);
+        return builder;
+    }
+
+    /// <summary>
+    /// Adds EonaCat LogStack with AdvancedLoggerFactory for enhanced features
+    /// </summary>
+    public static IHostApplicationBuilder AddAdvancedEonaCatLogging(
+        this IHostApplicationBuilder builder,
+        LogLevel minimumLevel = LogLevel.Trace,
+        TimestampMode timestampMode = TimestampMode.Utc)
+    {
+        if (builder == null)
+        {
+            throw new ArgumentNullException(nameof(builder));
+        }
+
+        builder.Services.AddAdvancedEonaCatLogging(minimumLevel, timestampMode);
+        return builder;
+    }
+
+    /// <summary>
+    /// Adds EonaCat LogStack with AdvancedLoggerFactory and a configuration callback
+    /// </summary>
+    public static IHostApplicationBuilder AddAdvancedEonaCatLogging(
+        this IHostApplicationBuilder builder,
+        Action<AdvancedLoggerFactory> configure)
+    {
+        if (builder == null)
+        {
+            throw new ArgumentNullException(nameof(builder));
+        }
+
+        if (configure == null)
+        {
+            throw new ArgumentNullException(nameof(configure));
+        }
+
+        builder.Services.AddAdvancedEonaCatLogging(configure);
+        return builder;
+    }
+
+    /// <summary>
+    /// Adds the AdvancedMetricsCollector for system-wide analytics
+    /// </summary>
+    public static IHostApplicationBuilder AddEonaCatMetricsCollection(
+        this IHostApplicationBuilder builder)
+    {
+        if (builder == null)
+        {
+            throw new ArgumentNullException(nameof(builder));
+        }
+
+        builder.Services.AddEonaCatMetricsCollection();
+        return builder;
+    }
 }

EonaCat.LogStack/Extensions/ServiceCollectionExtensions.cs

@@ -248,4 +248,93 @@ public static class ServiceCollectionExtensions
 
         return services.AddEonaCatLoggingFactory("Application", configure);
     }
+
+    /// <summary>
+    /// Registers EonaCat LogStack with AdvancedLoggerFactory for enhanced features like category-specific configuration and context propagation
+    /// </summary>
+    /// <param name="services">The service collection to register with</param>
+    /// <param name="minimumLevel">The minimum log level to process</param>
+    /// <param name="timestampMode">The timestamp mode to use</param>
+    /// <returns>The service collection for chaining</returns>
+    public static IServiceCollection AddAdvancedEonaCatLogging(
+        this IServiceCollection services,
+        LogLevel minimumLevel = LogLevel.Trace,
+        TimestampMode timestampMode = TimestampMode.Utc)
+    {
+        if (services == null)
+        {
+            throw new ArgumentNullException(nameof(services));
+        }
+
+        var advancedFactory = new AdvancedLoggerFactory(minimumLevel, timestampMode);
+        services.AddSingleton(advancedFactory);
+        services.AddSingleton<ILoggerFactory>(advancedFactory);
+        services.AddSingleton<Microsoft.Extensions.Logging.ILoggerFactory>(
+            new MicrosoftExtensionsLoggerFactoryAdapter(advancedFactory));
+
+        // Also register as ILogger for constructor injection
+        services.AddSingleton(sp => sp.GetRequiredService<AdvancedLoggerFactory>().CreateLogger("Default"));
+        services.AddSingleton(sp =>
+            new MicrosoftExtensionsLoggerAdapter(
+                sp.GetRequiredService<AdvancedLoggerFactory>().CreateLogger("Default")));
+
+        return services;
+    }
+
+    /// <summary>
+    /// Registers EonaCat LogStack with AdvancedLoggerFactory and a configuration callback
+    /// </summary>
+    /// <param name="services">The service collection to register with</param>
+    /// <param name="configure">Callback to configure the AdvancedLoggerFactory</param>
+    /// <returns>The service collection for chaining</returns>
+    public static IServiceCollection AddAdvancedEonaCatLogging(
+        this IServiceCollection services,
+        Action<AdvancedLoggerFactory> configure)
+    {
+        if (services == null)
+        {
+            throw new ArgumentNullException(nameof(services));
+        }
+
+        if (configure == null)
+        {
+            throw new ArgumentNullException(nameof(configure));
+        }
+
+        services.AddSingleton<AdvancedLoggerFactory>(sp =>
+        {
+            var factory = new AdvancedLoggerFactory();
+            configure(factory);
+            return factory;
+        });
+
+        services.AddSingleton<ILoggerFactory>(sp => sp.GetRequiredService<AdvancedLoggerFactory>());
+        services.AddSingleton<Microsoft.Extensions.Logging.ILoggerFactory>(sp =>
+            new MicrosoftExtensionsLoggerFactoryAdapter(sp.GetRequiredService<AdvancedLoggerFactory>()));
+
+        // Also register as ILogger for constructor injection
+        services.AddSingleton(sp => sp.GetRequiredService<AdvancedLoggerFactory>().CreateLogger("Default"));
+        services.AddSingleton(sp =>
+            new MicrosoftExtensionsLoggerAdapter(
+                sp.GetRequiredService<AdvancedLoggerFactory>().CreateLogger("Default")));
+
+        return services;
+    }
+
+    /// <summary>
+    /// Registers the AdvancedMetricsCollector for system-wide analytics
+    /// </summary>
+    /// <param name="services">The service collection to register with</param>
+    /// <returns>The service collection for chaining</returns>
+    public static IServiceCollection AddEonaCatMetricsCollection(
+        this IServiceCollection services)
+    {
+        if (services == null)
+        {
+            throw new ArgumentNullException(nameof(services));
+        }
+
+        services.AddSingleton<AdvancedMetricsCollector>();
+        return services;
+    }
 }

EonaCat.LogStack/LogBuilder.cs

@@ -28,6 +28,9 @@ public sealed class LogBuilder
     private TimestampMode _timestampMode = TimestampMode.Utc;
     private readonly List<IFlow> _flows = new();
     private readonly List<IBooster> _boosters = new();
+    private DynamicLevelController? _dynamicLevel;
+    private bool _useAsyncPipeline;
+    private int _asyncPipelineCapacity = 65536;
 
     public event EventHandler<LogMessage> OnLog;
 
@@ -991,6 +994,16 @@ public sealed class LogBuilder
             logger.AddBooster(booster);
         }
 
+        if (_dynamicLevel != null)
+        {
+            logger.UseDynamicLevel(_dynamicLevel);
+        }
+
+        if (_useAsyncPipeline)
+        {
+            logger.UseAsyncPipeline(_asyncPipelineCapacity);
+        }
+
         return logger;
     }
 
@@ -1080,4 +1093,113 @@ public sealed class LogBuilder
 
         lock (_flows) { _flows.RemoveAll(f => f.Name == name); }
     }
+
+    /// <summary>
+    /// Enables the Channel-based async dispatch pipeline for zero-blocking logging.
+    /// Events are enqueued to a <see cref="System.Threading.Channels.Channel{T}"/> and
+    /// consumed by a dedicated background Task.
+    /// </summary>
+    /// <param name="capacity">Bounded capacity (0 = unbounded).</param>
+    public LogBuilder UseAsyncPipeline(int capacity = 65536)
+    {
+        _useAsyncPipeline = true;
+        _asyncPipelineCapacity = capacity;
+        return this;
+    }
+
+    /// <summary>
+    /// Attaches a <see cref="DynamicLevelController"/> so the minimum log level can
+    /// be changed at runtime without restarting the application.
+    /// </summary>
+    public LogBuilder WithDynamicLevelController(DynamicLevelController controller)
+    {
+        _dynamicLevel = controller ?? throw new ArgumentNullException(nameof(controller));
+        return this;
+    }
+
+    /// <summary>
+    /// Wraps any flow with a Circuit Breaker that opens after repeated failures
+    /// and probes for recovery after a configurable timeout.
+    /// </summary>
+    public LogBuilder WriteToCircuitBreaker(
+        IFlow inner,
+        int failureThreshold = 5,
+        TimeSpan? recoveryTimeout = null,
+        LogLevel minimumLevel = LogLevel.Trace)
+    {
+        if (inner == null)
+        {
+            throw new ArgumentNullException(nameof(inner));
+        }
+
+        _flows.Add(new CircuitBreakerFlow(inner, failureThreshold, recoveryTimeout, minimumLevel));
+        return this;
+    }
+
+    /// <summary>
+    /// Wraps any flow with a predicate — events are forwarded only when the predicate returns true.
+    /// </summary>
+    public LogBuilder WriteToConditional(
+        IFlow inner,
+        Func<LogEvent, bool> predicate,
+        LogLevel minimumLevel = LogLevel.Trace)
+    {
+        if (inner     == null)
+        {
+            throw new ArgumentNullException(nameof(inner));
+        }
+
+        if (predicate == null)
+        {
+            throw new ArgumentNullException(nameof(predicate));
+        }
+
+        _flows.Add(new ConditionalFlow(inner, predicate, minimumLevel));
+        return this;
+    }
+
+    /// <summary>
+    /// Adds a <see cref="MulticastFlow"/> that fans events out to multiple inner flows in parallel.
+    /// Use <see cref="MulticastFlow.Add"/> to attach targets.
+    /// </summary>
+    public LogBuilder WriteToMulticast(
+        MulticastFlow multicast)
+    {
+        if (multicast == null)
+        {
+            throw new ArgumentNullException(nameof(multicast));
+        }
+
+        _flows.Add(multicast);
+        return this;
+    }
+
+    /// <summary>
+    /// Pushes log events to a Grafana Loki instance.
+    /// </summary>
+    public LogBuilder WriteToLoki(
+        string lokiUrl,
+        Dictionary<string, string>? labels = null,
+        int batchSize = 50,
+        int batchIntervalMs = 1000,
+        string? bearerToken = null,
+        string? basicUser = null,
+        string? basicPassword = null,
+        HttpClient? httpClient = null,
+        LogLevel minimumLevel = LogLevel.Trace)
+    {
+        _flows.Add(new LokiFlow(
+            lokiUrl, labels, batchSize, batchIntervalMs,
+            bearerToken, basicUser, basicPassword, httpClient, minimumLevel));
+        return this;
+    }
+
+    /// <summary>
+    /// Adds the <see cref="CallerInfoBooster"/> which captures caller member/file/line.
+    /// </summary>
+    public LogBuilder BoostWithCallerInfo()
+    {
+        _boosters.Add(new CallerInfoBooster());
+        return this;
+    }
 }

EonaCat.LogStack/LoggerDiagnostics.cs

@@ -16,6 +16,7 @@ public class LoggerDiagnostics
     public LogLevel MinimumLevel { get; set; }
     public long TotalLogged { get; set; }
     public long TotalDropped { get; set; }
+    public long TotalExceptions { get; set; }
     public int FlowCount { get; set; }
     public int BoosterCount { get; set; }
     public List<FlowDiagnostics> Flows { get; set; }

EonaCat.LogStack/LoggerMetrics.cs

@@ -0,0 +1,90 @@
+using EonaCat.LogStack.Analytics;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+
+namespace EonaCat.LogStack;
+
+// This file is part of the EonaCat project(s) which is released under the Apache License.
+// See the LICENSE file or go to https://EonaCat.com/License for full license details.
+
+/// <summary>
+/// Comprehensive metrics about the logger
+/// </summary>
+public class LoggerMetrics
+{
+    public long TotalLogged { get; set; }
+    public long TotalDropped { get; set; }
+    public long TotalExceptions { get; set; }
+    public long TotalBytes { get; set; }
+    public double WritesPerSecond { get; set; }
+    public long TraceCount { get; set; }
+    public long DebugCount { get; set; }
+    public long InformationCount { get; set; }
+    public long WarningCount { get; set; }
+    public long ErrorCount { get; set; }
+    public long CriticalCount { get; set; }
+    public long UptimeMilliseconds { get; set; }
+    public List<FlowStatisticsSnapshot> FlowMetrics { get; set; } = new();
+
+    /// <summary>
+    /// Gets the success rate (logged / (logged + dropped))
+    /// </summary>
+    public double SuccessRate
+    {
+        get
+        {
+            var total = TotalLogged + TotalDropped;
+            return total > 0 ? (TotalLogged * 100.0) / total : 100;
+        }
+    }
+
+    /// <summary>
+    /// Gets average bytes per event
+    /// </summary>
+    public double AverageBytesPerEvent
+    {
+        get => TotalLogged > 0 ? TotalBytes / (double)TotalLogged : 0;
+    }
+
+    /// <summary>
+    /// Returns formatted report
+    /// </summary>
+    public override string ToString()
+    {
+        var sb = new StringBuilder();
+        sb.AppendLine("===== LOGGER METRICS =====");
+        sb.AppendLine($"Total Logged: {TotalLogged:N0}");
+        sb.AppendLine($"Total Dropped: {TotalDropped:N0}");
+        sb.AppendLine($"Success Rate: {SuccessRate:F2}%");
+        sb.AppendLine($"Total Exceptions: {TotalExceptions:N0}");
+        sb.AppendLine($"Total Bytes: {TotalBytes:N0}");
+        sb.AppendLine($"Average Bytes/Event: {AverageBytesPerEvent:F2}");
+        sb.AppendLine($"Writes/Second: {WritesPerSecond:F2}");
+        sb.AppendLine();
+
+        sb.AppendLine("Events by Level:");
+        sb.AppendLine($"  Trace: {TraceCount:N0}");
+        sb.AppendLine($"  Debug: {DebugCount:N0}");
+        sb.AppendLine($"  Information: {InformationCount:N0}");
+        sb.AppendLine($"  Warning: {WarningCount:N0}");
+        sb.AppendLine($"  Error: {ErrorCount:N0}");
+        sb.AppendLine($"  Critical: {CriticalCount:N0}");
+        sb.AppendLine();
+
+        sb.AppendLine($"Uptime: {System.TimeSpan.FromMilliseconds(UptimeMilliseconds):hh\\:mm\\:ss}");
+
+        if (FlowMetrics.Count > 0)
+        {
+            sb.AppendLine();
+            sb.AppendLine("Flow Statistics:");
+            foreach (var flow in FlowMetrics)
+            {
+                sb.AppendLine($"  {flow.FlowName} ({flow.FlowType}): {flow.EventsProcessed:N0} events, {flow.SuccessRate:F2}% success");
+            }
+        }
+
+        sb.AppendLine("==========================");
+        return sb.ToString();
+    }
+}