RELEASE_NOTES.md

1.5.68 May 18th 2026

Security Fixes

• Resolve GHSA-g94r-2vxg-569j by bumping OpenTelemetry minimum to 1.10.0 - OpenTelemetry.Api 1.9.0 has a known moderate severity vulnerability. The minimum OpenTelemetry version floor has been raised from 1.9.0 to 1.10.0, and the Microsoft.Extensions.Logging floor has been raised to 9.0.0. Downstream consumers that previously resolved to the vulnerable OpenTelemetry.Api 1.9.0 will now pull the safe 1.10.0 release.

Bug Fixes

• Fix implicit-sender leak under xUnit v3 parallel execution in Akka.Hosting.TestKit - Under xUnit v3's default parallel-class scheduling, await continuations could resume on ThreadPool threads where a sibling test had pinned its actor cell, causing Tell() to use the wrong implicit sender and replies to land in the wrong TestActor's mailbox. A new wrapping SynchronizationContext preserves xUnit's scheduler while pinning the ambient actor cell across await continuations.
• Fix SynchronizationContext leak and TestActor startup race in Akka.Hosting.TestKit - Two compounding sources of flakiness in sequential xUnit v3 suites: (1) the ActorCellKeepingSynchronizationContext installed during host startup leaked out of the initialization callback and was inherited by subsequent tests, pinning continuations onto disposed ActorCells; (2) the TestActor created during host startup was intermittently terminated by a race with other /system actors starting concurrently. Fixed by bracketing the context installation with a save/restore and adding post-startup TestActor liveness verification with automatic re-creation.
• Fix cached TestProbe refs becoming stale after TestActor recovery in Akka.Hosting.TestKit - Actors created during WithActors could cache IRequiredActor<TestProbe>.ActorRef before recovery ran. Re-registering a new raw TestActor in ActorRegistry did not update those cached refs. TestProbe is now registered via a stable forwarding actor whose target is swapped atomically after recovery, ensuring all cached references remain valid.

1.5.67 April 26th 2026

New Features

• Add WithStrictSerialization helper — resolves issue #734. Adds WithStrictSerialization(bool enabled = true) extension on AkkaConfigurationBuilder that sets akka.actor.serialization-settings.allow-unregistered-types = off, disabling the Newtonsoft.Json fallback and throwing SerializationException for unregistered types.

Updates

• Bump Akka version from 1.5.66 to 1.5.67 - Hotfix release reverting the Task.Yield() optimization in AsyncWriteJournal/SnapshotStore that broke the persistence plugin threading contract.

1.5.65 April 10th 2026

Updates

• Bump Akka version from 1.5.64 to 1.5.65

1.5.64 March 31st 2026

Bug Fixes

• Fix LoggerFactoryLogger metadata regression for non-semantic logs - PR #706 (trace correlation) accidentally gated ActorPath, LogSource, Timestamp, and Thread emission on _hasSemanticProperties, which was false for plain-string logs. Non-semantic logs lost all structured metadata, breaking downstream consumers such as Datadog pipelines and custom ConsoleFormatters. All log paths now emit the full set of Akka metadata as structured attributes regardless of whether the message uses named placeholders.

Breaking Changes

• Convert Akka.Hosting.TestKit to xUnit 3 - Akka.Hosting.TestKit now targets xUnit v3. Users who need to remain on xUnit v2 can switch to the new Akka.Hosting.TestKit.Xunit2 package, which preserves the previous xUnit v2-based TestKit API.

Updates

• Bump Akka version from 1.5.63 to 1.5.64

1.5.63 March 24th 2026

Bug Fixes

• Fix ActorRegistry.TryGet caching stale IActorRef values - ActorRegistry.TryGet was caching the internal IActorRef on first call.

Updates

• Bump Akka version from 1.5.62 to 1.5.63

1.5.62 March 4th 2026

Updates

• Bump Akka version from 1.5.61 to 1.5.62

1.5.61 February 26th 2026

Updates

• Bump Akka version from 1.5.60 to 1.5.61

1.5.60 February 10th 2026

New Features

• Add OpenTelemetry trace correlation support for LoggerFactoryLogger - enables proper trace correlation for logs emitted from actor code. Solves the problem that Activity.Current doesn't flow across actor mailbox boundaries because it uses AsyncLocal<T>. When using Akka.NET 1.5.59+, LogEvent.ActivityContext captures trace context at log creation time and flows it through to OpenTelemetry LogRecords via the new AkkaTraceContextProcessor. Register with options.AddAkkaTraceCorrelation() in your OpenTelemetry logging configuration.
• Add WithContext() integration tests for MEL logger - confirmed that Akka.NET 1.5.60's WithContext() logging context enrichment works automatically with LoggerFactoryLogger. Context properties set via the core WithContext() API flow through to Microsoft.Extensions.Logging state dictionaries via TryGetProperties() without any code changes needed.

Bug Fixes

• Fix WithDefaultLogMessageFormatter<T>() rejecting built-in formatters - SemanticLogMessageFormatter and DefaultLogMessageFormatter have private constructors (they use singleton Instance properties), but the validation only accepted public parameterless constructors. These built-in types are now correctly accepted.

Deprecations

• WithDefaultLogMessageFormatter<T>() is now marked [Obsolete] — SemanticLogMessageFormatter is the default as of Akka.NET 1.5.58 and no longer needs to be set explicitly. The method still works for custom ILogMessageFormatter implementations.

Updates

• Bump Akka version from 1.5.59 to 1.5.60

1.5.60-beta1 January 29th 2026

Beta Release

This is a beta release for testing the OpenTelemetry trace correlation feature that was merged after 1.5.59.

New Features

• Add OpenTelemetry trace correlation support for LoggerFactoryLogger - enables proper trace correlation for logs emitted from actor code. Solves the problem that Activity.Current doesn't flow across actor mailbox boundaries because it uses AsyncLocal<T>. When using Akka.NET 1.5.59+, LogEvent.ActivityContext captures trace context at log creation time and flows it through to OpenTelemetry LogRecords via the new AkkaTraceContextProcessor. Register with options.AddAkkaTraceCorrelation() in your OpenTelemetry logging configuration.

1.5.59 January 2026

New Features

• Add OpenTelemetry trace correlation support for LoggerFactoryLogger - enables proper trace correlation for logs emitted from actor code. Solves the problem that Activity.Current doesn't flow across actor mailbox boundaries because it uses AsyncLocal<T>. When using Akka.NET 1.5.59+, LogEvent.ActivityContext captures trace context at log creation time and flows it through to OpenTelemetry LogRecords via the new AkkaTraceContextProcessor. Register with options.AddAkkaTraceCorrelation() in your OpenTelemetry logging configuration.

Bug Fixes

• Fix semantic logging not capturing named placeholders as structured properties - resolved issue #701 where named placeholders like {Event} in log messages were not captured as searchable structured properties. Made all LoggerConfigBuilder properties optional and refactored message formatting code.
• Fix TestKit startup timeout race condition - resolved race condition in TestKit.InitializeAsync() where CancellationTokenSource.Register() threw exceptions on the timer thread, causing unhandled exceptions that crashed the test host process. Also increased default startup timeout from 10s to 30s for CI environments.

Updates

• Bump Akka version from 1.5.58 to 1.5.59
• Added OpenTelemetry package dependency (1.9.0+) for trace correlation support

1.5.58 January 9th 2026

Updates

• Bump Akka version from 1.5.57 to 1.5.58

1.5.57 December 16th 2025

New Features

• Add semantic logging support for Akka.NET 1.5.56+ - enables Microsoft.Extensions.Logging to receive properly structured state dictionaries instead of pre-formatted strings. When using Akka.NET 1.5.56+, log messages now include structured properties from the semantic logging API along with Akka metadata (ActorPath, Timestamp, Thread, LogSource). Fully backwards compatible with older Akka.NET versions.

Updates

• Bump Akka version from 1.5.55 to 1.5.57

1.5.55.1 October 27th 2025

Enhancements

• Expose options in journal and snapshot builders - resolved issue #690 by adding Options property to AkkaPersistenceJournalBuilder and AkkaPersistenceSnapshotBuilder. Extension methods can now access configuration details without requiring options as explicit parameters, eliminating redundant option passing for connectivity health checks and other plugin-specific features

1.5.55 October 26th 2025

New Features

• Support custom health check registrations on Journal and Snapshot Builders - added API to support custom health check registrations for Akka.Persistence plugins, related to issue #678
• Add support for custom certificate validation callbacks - integrated the new CertificateValidationCallback feature from Akka.NET v1.5.55, allowing users to provide custom certificate validation logic for SSL/TLS connections. Enables advanced scenarios including certificate pinning, subject/issuer matching, custom business validation rules, and advanced mTLS scenarios

Enhancements

• Add customizable tags parameter to health check methods - resolved issue #679 by adding new overload allowing custom tags for health checks while maintaining backward compatibility
• Made it easier to customize failureState and tags for all health checks - simplified health check configuration API for all health checks

Updates

• Bump Akka version from 1.5.53 to 1.5.55

1.5.55-beta1 October 26th 2025

New Features

• Support custom health check registrations on Journal and Snapshot Builders - added API to support custom health check registrations for Akka.Persistence plugins, related to issue #678

Enhancements

• Add customizable tags parameter to health check methods - resolved issue #679 by adding new overload allowing custom tags for health checks while maintaining backward compatibility
• Made it easier to customize failureState and tags for all health checks - simplified health check configuration API for all health checks

Updates

• Bump Akka version from 1.5.53 to 1.5.55

1.5.53 October 14th 2025

Bug Fixes

• Fix event adapter callback API not invoking adapters at runtime - resolved critical bug where event adapters configured via the callback API were not being invoked at runtime. This fix is especially important for users who have migrated to the callback pattern following the deprecation of JournalOptions.Adapters property. The issue was caused by unnecessary fallback configuration that interfered with adapter registration during HOCON merging.

Updates

• Add SSL/TLS configuration settings from Akka.NET 1.5.52 and 1.5.53 - updated SSL/TLS configuration options to support new features and settings introduced in Akka.NET versions 1.5.52 and 1.5.53
• Bump Akka version from 1.5.52 to 1.5.53

1.5.52 October 9th 2025

API Changes

• Deprecate JournalOptions.Adapters property in favor of callback API - resolved issue #665 by deprecating the JournalOptions.Adapters property. Users should migrate to the unified callback pattern: builder.WithJournal(options, journal => journal.AddWriteEventAdapter<T>(...)). The deprecated property will be removed in v1.6.0.

Updates

• Bump Akka version from 1.5.51 to 1.5.52

1.5.51.1 October 2nd 2025

Bug Fixes

• Fix journal health check registration without event adapters - resolved issue #666 where journal health checks were not being registered when using .WithHealthCheck() without adding event adapters

1.5.51 October 1st 2025

New Features

• Added Akka.Persistence health checks - health check support for Akka.Persistence journal and snapshot stores with unified configuration API
• Added dependency-injected health checks - WithHealthCheck<T>() generic methods for DI-resolved health checks

Updates

• Bump Akka version from 1.5.50 to 1.5.51