1.5.58 January 8th, 2026

Akka.NET v1.5.58 is a maintenance release with important bug fixes and performance improvements.

.NET 10 Compatibility Fix

• Fix .NET 10 CLR shutdown hook breaking change - Resolves an issue where the CLR shutdown hook behavior changed in .NET 10, ensuring graceful actor system termination works correctly.

Bug Fixes

• Fix TcpListener to not stop accepting connections on transient accept errors - The TcpListener now properly handles transient socket accept errors without stopping to accept further connections.
• Fix race condition in cluster sharding when entity constructor fails - Resolves a race condition that could occur when an entity actor's constructor throws an exception.
• Fix race condition in QueueSink causing async enumerable timeout - Fixes a race condition in QueueSink that could cause timeouts when using async enumerables.
• Make RemotingTerminator non-FSM to avoid racy FSM log init - Fixes potential race conditions during actor system shutdown logging.

Performance Improvements

• LogMessage GetProperties without FrozenDictionary - Improves semantic logging performance by avoiding FrozenDictionary allocations in hot paths.
• Skip parsing PropertyNames when empty Parameters - Additional logging optimization that skips unnecessary parsing when log messages have no parameters.

New Features

• Akka.TestKit: configurable expect-no-message-default value - Fixes issue #6675. You can now configure the default timeout for ExpectNoMsg() via HOCON:

  akka.test.expect-no-message-default = 100ms
  

6 contributors since release 1.5.57

| COMMITS | LOC+ | LOC- | AUTHOR | |---------|------|------|---------------------| | 7 | 158 | 36 | Aaron Stannard | | 2 | 483 | 55 | Gregorius Soedharmo | | 2 | 11 | 41 | Rolf Kristensen | | 1 | 100 | 22 | Yaroslav Paslavskiy | | 1 | 37 | 53 | Jarkko Pöyry | | 1 | 11 | 2 | Petri Kero |

Changes:

• c51ab05820fa4e292106715b979fded4ed6dd2a2 Add release notes for Akka.NET v1.5.58 (#7985)
• 45e7f45871ae7a33ce0ce258fb45fead1a6557f0 Update API approval list
• cca19865c611ffe10704a9b4dee1df03bda0d2a8 LogMessage GetProperties without FrozenDictionary (#7968)
• b22808e3baa19f376c982d0f9655027ac1c9fc39 Akka.TestKit: configurable expect-no-message-default value #6675 (#7006)
• efd3f0da8c42e05bee050a7b9854289075fde8ed Fix .NET 10 CLR shutdown hook breaking change (#7964)
• 8027265086d36c9737a86f499201b377bc61061e Make RemotingTerminator non-FSM to avoid racy FSM log init. (#7967)
• 0e8480e18f836a5b705cc8dd7fe6bc23ee6c9880 Fix timing race in BackpressureTimeout_must_succeed_if_subscriber_demand_arrives test (#7972)
• 8aad0c3c9d45819ed6067bfa748151181ff72751 Fix race condition in QueueSink causing async enumerable timeout (#7973)
• feb1102edf71b694df9bd3b4f08e0fd063a8e265 Fix race condition in multi-producer sharding delivery test (#7975)
• 25cef789d726dc8cd012a85c0b5fcbef9d26b236 Fix WithinAsync timeout not propagating to EventFilter across async boundaries (#7977)