1.5.48 August 21st, 2025

Akka.NET v1.5.48 is a minor patch containing stability improvement to Akka.TestKit.

• TestKit: Fix deadlock during parallel test execution

2 contributors since release 1.5.47

To see the full set of changes in Akka.NET v1.5.48, click here

Changes:

• 1f4c6d2 Update RELEASE_NOTES.md for 1.5.48 release (#7788)
• 0bfe2fc Port #7772 - TestKit: synchronous TestActor start (#7787) [ #7770 ]
• 1f14b74 Convert Akka.Cluster.Sharding.Tests.MultiNode to async (#7758)
• 31adf92 Convert Akka.Cluster.Tests.MultiNode specs to async (#7755)
• 89e6405 Convert Akka.Cluster.Tools multi-node tests to async (#7757)
• f422b79 Update RELEASE_NOTES.md for 1.5.48 nightly (#7760)
• 43f3e52 Convert Akka.Remote.Tests.MultiNode specs to async (#7756)

This list of changes was auto generated.

1.5.47 August 12th, 2025

Akka.NET v1.5.47 is a minor patch containing several stability improvements to Akka.TestKit.

• TestKit: Replace Thread.Sleep with SpinWait
• TestKit: Fix excessive AggregateException nesting when cancelling ExpectMessageAsync
• TestKit: Add async overload to multi-node TestConductor API
• Core: Move ByteBuffer alias to global using

4 contributors since release 1.5.46

To see the full set of changes in Akka.NET v1.5.47, click here

Changes:

• 83e4bcc Update RELEASE_NOTES.md for 1.5.47 release (#7759)
• eef6fe5 Convert SBR multi-node tests to async (#7754)
• 599e13b Convert ClusterRoundRobinSpec to async (#7752)
• 79ec342 move ByteBuffer alias to a global using (#7681)
• f1962c6 Add async overloads to multi-node TestConductor APIs (#7750) [ #4146 ]
• 673f56f Fix excessive exception nesting when cancelling ExpectMsgAsync (#7747) [ #7743 ]
• 28a80b5 Bump actions/checkout from 4 to 5 (#7751)
• f9a1835 Update RELEASE_NOTES.md for 1.5.47 nightly build (#7749)
• a7955cb Fix race condition in AllEventsSpec by using async/await (#7748) [ #7711 ]
• 1c44ee3 add worktrees to .gitignore (#7746)

1.5.46 July 17th, 2025

Akka.NET v1.5.46 is a minor patch containing a fix for the Akka.IO.Dns extension.

• Core: Resolve ManagerClass type from IDnsProvider

3 contributors since release 1.5.45

To see the full set of changes in Akka.NET v1.5.46, click here

Changes:

• dbca4de Update RELEASE_NOTES.md for 1.5.46 release (#7733)
• 000d75b DnsExt: Resolve ManagerClass Type from IDnsProvider (#7727)
• c10cfc1 docs: added Akka.Cluster SBR video to docs (#7725)
• 3994208 Exclude Akka.Cluster.Cpu.Benchmark from nuget pack (#7724)

This list of changes was auto generated.

1.5.45 July 7th, 2025

Akka.NET v1.5.45 is a minor patch containing bug fixes for Core Akka and Akka.Cluster.Sharding plugin.

• Core: Code modernization, use deconstructor for variable swapping
• Sharding: Fix unclean ShardingConsumerControllerImpl shutdown
• Core: Convert Failure to Exception for Ask<object>
• Core: Fix Settings.InjectTopLevelFallback race condition
• Sharding: Make remembered entities honor supervision strategy decisions

Supervision Strategy For Sharding Remembered Entities

• We've added a SupervisorStrategy property to ClusterShardingSettings. You can use any type of SupervisionStrategy, but it is recommended that you inherit ShardSupervisionStrategy if you're making your own custom supervision strategy.
• Remembered shard entities will now honor SupervisionStrategy decisions and stops remembered entities if the SupervisionStrategy.Decider returned a Directive.Stop or if there is a maximum restart retry limitation.

4 contributors since release 1.5.44

To see the full set of changes in Akka.NET v1.5.45, click here

Changes:

• 8f294a9 Update RELEASE_NOTES for 1.5.45 release (#7723)
• ddbfa77 Update RELEASE_NOTES.md for 1.5.45 release (#7722)
• ec8a419 Stop failing remembered entity if supervisor strategy failed (#7720)
• 857801c Fix Settings.InjectTopLevelFallback race condition (#7721)
• 65ba0f4 Cleanup Jetbrains Rider analyzer warnings (#7719)
• 752e73a convert Failure to exception when using Ask (#7286)
• a789dd7 [DOCS] Improve DistributedPubSub XML-DOC (#7718)
• 16ce2d3 Cleanup unreachable code and XML-DOC warnings (#7715)
• b49b47b Fix unclean ShardingConsumerControllerImpl shutdown (#7714)
• 706d95d swap using deconstruction (#7658)
See More

• 01c3a71 enable TreatWarningsAsErrors (#7708)
• d8f4ddc [F#] Refactor double underscore to single (#7705)
• 2c7cd4d Cleanup Akka.Streams build warnings (#7707)
• 393e2f5 Clean build warnings (#7703)

This list of changes was auto generated.

1.5.44 June 19th, 2025

Akka.NET v1.5.44 is a minor patch that contains a bug fix to the Akka.Persistence plugin.

• Persistence: Make sure that EventSourced timer is canceled when persistent actor is stopped

3 contributors since release 1.5.43

To see the full set of changes in Akka.NET v1.5.44, click here.

Changes:

• 3dce08d Update RELEASE_NOTES.md for 1.5.44 release (#7706)
• f574570 [DOCS] Fix sharding query documentation (#7704)
• 1b38074 [FSharp] Clean build warnings (#7702)
• ee038ad Cleanup build warnings (#7701)
• 8fe603f Cleanup build warnings (#7700)
• bf6da82 Clean build warnings (#7699)
• 5f3656b Clean build warnings (#7698)
• 432b0e4 Clean build warnings (#7697)
• 6e479e2 Cleanup ClusterSingletonApiSpec build warnings (#7695)
• 727fab3 Clean build warnings (#7694)

1.5.43 June 10th, 2025

Akka.NET v1.5.43 contains several bug fixes and also adds new quality of life features.

• Cluster.Tools: Fix PublishWithAck response message type
• Sharding: Allows sharding delivery consumer to passivate self
• TestKit: Fix CallingThreadDispatcher async context switching
• Persistence.Query: Add non-generic ReadJournalFor API method
• Core: Simplify null checks
• Core: Propagate CoordinatedShutdown reason to application exit code
• Core: Bump AkkaAnalyzerVersion to 0.3.3
• Core: Improve IScheduledTellMsg DeadLetter log message

New Akka.Analyzer Rules

We've added three new Akka.Analyzer rules, AK2003, AK2004, and AK2005. All of them addresses the same Akka anti-pattern where a void async delegate is being passed into the ReceiveActor.Receive<T>() (AK2003), IDslActor.Receive<T>() (AK2004), and ReceivePersistentActor.Command<T>() (AK2005) message handlers.

Here are the documentation for each new rules:

• AK2003 documentation
• AK2004 documentation
• AK2005 documentation

4 contributors since release 1.5.42

To see the full set of changes in Akka.NET v1.5.43, click here.

What's Changed

• DOCS: Fix PublishWithAck documentation by @Arkatufus in #7671
• Fix PublishWithAck response message type by @Arkatufus in #7673
• Allow sharding delivery consumer to passivate self by @Arkatufus in #7670
• Unset ActorCellKeepingSynchronizationContext in CallingThreadDispatcher by @schdooz in #7674
• [Query] Add non-generic ReadJournalFor API by @Arkatufus in #7679
• Add AK2003/AK2004/AK2005 documentation by @Arkatufus in #7682
• Add FilterOnFallbackPort documentation by @Arkatufus in #7683
• simplify some null checks by @SimonCropp in #7659
• Propagate CoordinatedShutdown reason to application exit code by @Arkatufus in #7684
• Bump AkkaAnalyzerVersion to 0.3.3 by @Arkatufus in #7685
• Improve ScheduledTellMsg logging by @Arkatufus in #7686
• Update RELEASE_NOTES.md for 1.5.43 release by @Arkatufus in #7687

New Contributors

• @schdooz made their first contribution in #7674

Full Changelog: 1.5.42...1.5.43

1.5.42 May 21st, 2025

Akka.NET v1.5.42 contains several bug fixes and also adds new quality of life features to Akka.IO.Tcp, Akka.Persistence, Akka.Pattern, and Akka.Cluster.Tools.DistributedPubSub.

• IO.Tcp: Cleanup API
• IO.Tcp: Fix TcpListener connection queue problem
• Persistence: Allow user to use supervision strategy on journal and snapshot store
• Core: Add cancellation token to CircuitBreaker API to signal timed out operations
• Persistence: Change all CircuitBreaker protected method API to use cancellation token
• Core: Leverage Exception...when pattern
• IO.Tcp: Add TcpListenerStatistics and subscription methods
• Cluster.Tools: Modernize DistributedPubSub code
• Cluster.Tools: Optimize DistributedPubSub memory allocation
• Cluster.Tools: Improve DistributedPubSub DeadLetter log message
• Core: Refactor immutable collection builders to use simpler CreateBuilder pattern
• IO.Tcp: Redesign TcpConnection
• Cluster.Tools: Add PublishWithAck feature to DistributedPubSub

Akka.Pattern.CircuitBreaker

Backward compatible API changes:

• New .WithCircuitBreaker() APIs were added that changes the protected function delegate to accept a new CancellationToken argument.
• Old .WithCircuitBreaker() APIs were marked as obsolete.

Akka.Cluster.Tools.DistributedPubSub

The documentation for the new PublishWithAck feature can be read here

Backward compatible API changes:

• There is a new DistributedPubSubSettings constructor that leverages the new PublishWithAck feature. The old constructor is marked as obsolete.

Akka.Persistence

The documentation for the new supervision strategy for journal and snapshot-store feature can be read here

Breaking API changes:

Due to changes in CircuitBreaker.WithCircuitBreaker() APIs, several Akka.Persistence journal and snapshot-store were changed in a breaking manner. You will need to consider these changes if you have your own specific Akka.Persistence plugin implementation and needed to upgrade to this version of Akka.

• AsyncWriteJournal
  • DeleteMessagesToAsync()
  • ReadHighestSequenceNrAsync()
  • WriteMessagesAsync
• SnapshotStore
  • Both DeleteAsync() methods
  • LoadAsync()
  • SaveAsync()

Akka.IO.Tcp

The Akka.IO.Tcp has been redesigned to improve its reliability, visibility, and performance. This, unfortunately, requires some breaking changes to be introduced into the code base.

New features:

• The TcpListener actor now accepts a new SubscribeToTcpListenerStats message. Subscribers will receive regular TcpListenerStatistics metrics report from the TcpListener.
• The new UnsubscribeFromTcpListenerStats message can be used to unsubscribe from the TcpListener

Backward compatible changes:

• The Akka.IO.Tcp.Bind command now contain a new settable TcpSettings property.
• The Akka.IO.Tcp.Connect command now contain a new settable TcpSettings property.
• The Akka.IO.TcpSettings class have several of its unused properties deprecated and/or changed:
  • The ReceivedMessageSizeLimit property has been deprecated, replaced with the new MaxFrameSizeBytes property.
  • New ReceiveBufferSize property added.
  • New SendBufferSize property added.

Breaking API changes:

• Akka.IO.Tcp.Instance static field has been removed.
• Akka.IO.TcpExt.BufferPool static property has been removed.

To see the full set of changes in Akka.NET v1.5.42, click here.

5 contributors since release 1.5.41

What's Changed

• Akka.Benchmark: harden TcpOperationsBenchmark by @Aaronontheweb in #7620
• Akka.IO.Tcp: cleaning up TBDs and API junk by @Aaronontheweb in #7621
• Akka.IO: fix TcpListener connection queue problem by @Aaronontheweb in #7623
• Feature/7582 by @Danthar in #7595
• Convert flaky SelectAsync test to [Fact] for CI validation by @CodingPythonMan in #7625
• Introduce CancellationToken to WithCircuitBreaker by @Arkatufus in #7624
• leverage exception when by @SimonCropp in #7614
• Akka.IO: added TcpListenerStatistics and subscription methods by @Aaronontheweb in #7633
• Try Incrementalist 1.1.0-beta1 by @Aaronontheweb in #7635
• Remove unused Build stage from REAME.md by @Aaronontheweb in #7636
• Akka.IO Benchmarks: cache outbound Tcp.Write by @Aaronontheweb in #7638
• Modernize DistributedPubSub code by @Arkatufus in #7640
• docs: add real Akka.Discovery and Akka.Management documentation to the website by @Aaronontheweb in #7641
• Akka.Actor: remove TBDs by @Aaronontheweb in #7643
• Akka.Benchmarks: adding ActorPath.GetHashCode benchmarks by @Aaronontheweb in #7645
• Optimize DistributedPubSub memory allocation by @Arkatufus in #7642
• DistributedPubSub: clearer logging when DeadLetter publishing due to no subscribers by @Aaronontheweb in #7646
• Akka.Benchmarks: run real duplex messaging over Akka.IO.Tcp by @Aaronontheweb in #7651
• Akka.IO: validate we don't lose data when processing Tcp.Received by @Aaronontheweb in #7648
• remove redundant field initialization in ImmutableDictionaryKeepOrder by @SimonCropp in #7655
• remove TestValue output by @SimonCropp in #7653
• use simpler CreateBuilder API for immutabled collection builders by @SimonCropp in #7656
• Akka.IO: redesign TcpConnection by @Aaronontheweb in #7637
• Add wait-for-subscribers feature by @Arkatufus in #7652
• Add PublishWithAck documentation by @Arkatufus in #7665
• Update RELEASE_NOTES.md for 1.5.42 release by @Arkatufus in #7668

Full Changelog: 1.5.41...1.5.42

1.5.41 May 6th, 2025

Akka.NET v1.5.41 contains several bug fixes and also adds new quality of life features to Akka.TestKit and Akka.Streams.

• TestKit: Ensure that EventFilter respects WithinAsync timeout blocks
• TestKit: Add support to XUnit 3 to Akka.TestKit.Xunit
• TestKit: Improve ExpectNextNAsync() error message clarity
• Remoting: Mark IDaemonMsg with public interface marker
• Streams: Fix cancelled sinks are blocking other BroadcastHub consumers
• Streams: Allow GroupBy to use infinite output sub-streams
• Analyzers: Bump Akka.Analyzers from 0.3.1 to 0.3.2

XUnit V3 Support

We've added XUnit v3 support to Akka.TestKit.Xunit, please use this package if you're planning on using and/or migrating to the latest XUnit 3 platform.

Note that due to XUnit v3 limitation, please make sure that you're following these minimum requirements:

• Use net472 and above if you're targeting .NET Framework.
• Use net8.0 and above if you're targeting .NET Core.
• Reference the xunit.v3.* packages v2.0.2 and above.
• Reference the xunit.runner.visualstudio package v3.1.0 and above.

Akka.Streams GroupBy API improvement

Akka.Streams GroupBy stage can now, and now by default, create an unlimited number of sub-streams. Simply omit the maxSubstreams parameter or change the maxSubstreams parameter to a negative value to enable this feature.

4 contributors since release 1.5.40

To see the full set of changes in Akka.NET v1.5.40, click here.

Changes:

• 50478bf Update RELEASE_NOTES.md for 1.5.41 release (#7619)
• 976fa28 Akka.Benchmarks: categorize and cleanup core Akka benchmarks (#7618)
• ea68408 Fix 7578 (#7615)
• 98ebc72 Improve ExpectNextNAsync error message clarity (#7616)
• cdd1436 Add xunit.v3 implementation (#7612)
• db93be5 remove redundant catch (#7613)
• f901977 Bump Akka.Analyzer from 0.3.1 to 0.3.2 (#7609)
• 409cb2c Set package website to https://getakka.net/ (#7610)
• e25de09 Fix Akka.Persistence.Custom bug (#7608)
• 2eb59c5 [Streams] Allow GroupBy with infinite output substreams (#7607)

1.5.40 March 24th, 2025

• Remote: Endpoint actor cleanup
• Streams: Implement nullability in Buffer
• Streams: Refactor SelectAsyncUnordered ContinueWith to local function
• Core: Cleanup build warnings
• Streams: Make SelectAsync check equality by reference instead of by struct value
• Query.InMemory: Properly unwrap tagged messages in all queries
• Resolve Akka.Delivery and Akka.Cluster.Sharding.Delivery issues
• Persistence: Remove Akka.Persistence.Sql.Common and Akka.Persistence.Query.Sql packages
• Persistence: Remove Akka.Persistence.Sqlite

2 contributors since release 1.5.39

To see the full set of changes in Akka.NET v1.5.40, click here.

Changes:

• 8ab24c1 Update 1.5.40 release notes (#7576)
• f56ebb3 Build Warnings: Miscellanous (#7575)
• 15e5d8b fixed TestKit build warnings (#7572)
• 4471d6a fixed all ClusterSingletonManager.DefaultConfig() build warnings (#7571)
• 1f9a678 Akka.DistributedData.Tests: resolved all build warnings (#7570)
• 8ccc78e Akka.Remote: fixed all build warnings (#7567)
• b2661ac Akka.Cluster: Fix AK1004 warnings (#7279)
• 09e7e50 Akka.Tests: fixed build warnings (#7569)
• be32427 Akka.TestKit.Tests: fix build warnings (#7568)
• 2564c51 harden QueueSinkSpec (#7566)

1.5.39 March 14th, 2025

Akka.NET v1.5.39 contains a mission-critical bugfix for most Akka.Streams users.

• Akka.Cluster.Sharding: recursively unpack ShardingEnvelope contents inside IMessageExtract.EntityMessage - fixed a small edge case bug that could cause the ShardingEnvelope to be delivered to actors rather than the content inside the envelope.
• Akka.Util: improve Result<T> - small set of API changes here aimed at making Akka.Streams easier to reason about.
• Akka.Streams: Fixed race conditions + unsafe struct assignment in SelectAsync - this is a bug that's popped up in Akka.Persistence.Sql, Akka.Streams.Kafka, and many other places where SelectAsync is used: #7518

3 contributors since release 1.5.38

To see the full set of changes in Akka.NET v1.5.39, click here.

Changes:

• b1973cb Added v1.5.39 release notes (#7525)
• 02c8a24 Update target frameworks from net7.0/netcoreapp3.1 to net8.0 (#7523)
• 253973e Fixed race conditions + unsafe struct assignment in SelectAsync (#7521) [ #7518 ]
• 10b8223 Akka.Util: improve Result<T> (#7520)
• 6a5c7c0 Update persistence-testing.md docs (#7516)
• 3ca3682 Add SelectAsync regression test for Akka.Persistence.Sql (#7515)
• e25af24 Added "Why Learn Akka.NET?" video to homepage (#7511)
• 5957510 Update RELEASE_NOTES.md
• 2784f34 Have ShardingAdapter recursively call the underlying IMessageExtractor (#7474) [ #7470 ]

This list of changes was auto generated.