event-listener

Notify async tasks or threads

5.4.2 498M downloads/mo #226 most downloaded on crates.io smol-rs/event-listener

What this package is like to depend on

Last release 27 days ago

27 Jul 2026

Ships unpredictably

gaps range from 1 weeks to 12 months

Nearly every release is documented

notes for 35 of 35 stable releases

Nothing withdrawn

no release was ever pulled

6 years old

35 releases · first in 2020

1 release in the last 12 months

see the full history below

Release timeline

35 releases · May 2020 to Jul 2026

2021 2022 2023 2024 2025 2026

Release Pre-release

Releases

latest 35

5.4.2 27 Jul 2026
Release notes
- Add spinlock implementation to intrusive.rs.
- Remove slab-based implementation of event-listener. #109
- Fix unbounded Send/Sync implementations on StackSlot. #163
- Misc. internal improvements.
Open source →
Release notes
- Add spinlock implementation to intrusive.rs.
- Remove slab-based implementation of event-listener. #109
- Fix unbounded Send/Sync implementations on StackSlot. #163
- Misc. internal improvements.
Open source →
5.4.1 03 Aug 2025
Release notes
- Fix a copy-paste error in wait_timeout docs (#152)
Open source →
Release notes
- Fix a copy-paste error in wait_timeout docs (#152)
Open source →
5.4.0 08 Jan 2025
Release notes
- Add a no_std implementation based on the critical-section crate, enabled
  via the feature of the same name. (#148)
Open source →
Release notes
- Add a no_std implementation based on the critical-section crate, enabled via the feature of the same name. (#148)
Open source →
5.3.1 29 May 2024
Release notes
- Disable some optimizations that, in rare conditions, can cause race conditions
  causing notifications to be dropped. (#139)
- Ensure the portable-atomic feature is set properly. (#134)
- Update portable-atomic-util to v0.2.0. (#132)
- Document the std feature. (#134)
Open source →
Release notes
- Disable some optimizations that, in rare conditions, can cause race conditions causing notifications to be dropped. (#139)
- Ensure the portable-atomic feature is set properly. (#134)
- Update portable-atomic-util to v0.2.0. (#132)
- Document the std feature. (#134)
Open source →
5.3.0 05 Apr 2024
Release notes
- Add a loom implementation. This feature is unstable and is not semver-supported. (#126)
- Make the panic message for polling the EventListener after it has completed more clear. (#125)
Open source →
Release notes
- Add a loom implementation. This feature is unstable and is not semver-supported. (#126)
- Make the panic message for polling the EventListener after it has completed more clear. (#125)
Open source →
5.2.0 29 Feb 2024
Release notes
- Make StackSlot Sync. (#121)
Open source →
Release notes
- Make StackSlot Sync. (#121)
Open source →
5.1.0 18 Feb 2024
Release notes
- Make StackSlot Send. (#119)
Open source →
Release notes
- Make StackSlot Send. (#119)
Open source →
5.0.0 05 Feb 2024
Release notes
- Breaking: Rework the API to afford better usage. (#105)
  - The heap-based API of the v2.x line is back.
  - However, there is a stack-based API as an alternative.
- Add a way to get the total number of listeners. (#114)
Open source →
Release notes
- Breaking: Rework the API to afford better usage. (#105)
  - The heap-based API of the v2.x line is back.
  - However, there is a stack-based API as an alternative.
- Add a way to get the total number of listeners. (#114)
Open source →
4.0.3 06 Jan 2024
Release notes
- Relax MSRV to 1.60. (#110)
Open source →
Release notes
- Relax MSRV to 1.60. (#110)
Open source →
4.0.2 01 Jan 2024
Release notes
- Avoid spinning in wait_deadline. (#107)
Open source →
Release notes
- Avoid spinning in wait_deadline. (#107)
Open source →
4.0.1 19 Dec 2023
Release notes
- Fix a use-after-move error after an EventListener is assigned to listen to another Event. (#101)
Open source →
4.0.0 19 Nov 2023
Release notes
- Breaking: Fix a footgun in the EventListener type. EventListener::new() now no longer takes an &Event as an argument, and EventListener::listen() takes the &Event as an argument. Hopefully this should prevent .awaiting on a listener without making sure it's listening first. (#94)
Open source →
3.1.0 13 Nov 2023
Release notes
- Implement UnwindSafe and RefUnwindSafe for EventListener. This was unintentionally removed in version 3 (#96).
Open source →
3.0.1 29 Oct 2023
Release notes
- Emphasize that listen() must be called on EventListener in documentation. (#90)
- Write useful output in fmt::Debug implementations. (#86)
Open source →
3.0.0 10 Sep 2023
Release notes
- Use the parking crate instead of threading APIs (#27)
- Bump MSRV to 1.59 (#71)
- Breaking: Make this crate no_std-compatible on default-features = false. (#34)
- Create a new event-listener-strategy crate for abstracting over blocking/non-blocking operations. (#49)
- Breaking: Change the EventListener API to be !Unpin. (#51)
- Enable a feature for the portable-atomic crate. (#53)
- Breaking: Add a Notification trait which is used to enable tagged events. (#52)
- Add an is_notified() method to Event. (#48)
- Breaking: Make it so notify() returns the number of listeners notified. (#57)
Open source →
2.5.3 27 Jul 2022
Release notes
- Fix fence on x86 and miri.
Open source →
2.5.2 22 Jan 2022
Release notes
- Fix stacked borrows violation when -Zmiri-tag-raw-pointers is enabled. (#24)
Open source →
2.5.1 22 Sep 2020
Release notes
- Replace spinlock with a mutex.
Open source →
2.5.0 22 Sep 2020
Release notes
- Add EventListener::discard().
Open source →
2.4.0 20 Aug 2020
Release notes
- Event::new() is now a const fn.
Open source →
2.3.3 07 Aug 2020
Release notes
- Fix a bug in List::insert() that was causing deadlocks.
Open source →
2.3.2 05 Aug 2020
Release notes
- Optimization: use a simple spinlock and cache an Entry for less allocation.
Open source →
2.3.1 05 Aug 2020
Release notes
- Optimization: don't initialize Inner when notifying Event.
Open source →
2.3.0 31 Jul 2020
Release notes
- Implement UnwindSafe/RefUnwindSafe for Event/EventListener.
Open source →
2.2.1 24 Jul 2020
Release notes
- Always keep the last waker in EventListener::poll().
Open source →
2.2.0 02 Jul 2020
Release notes
- Add EventListener::same_event().
Open source →
2.1.0 02 Jul 2020
Release notes
- Add EventListener::listens_to().
Open source →
2.0.1 24 Jun 2020
Release notes
- Replace usize::MAX with std::usize::MAX.
Open source →
2.0.0 27 May 2020
Release notes
- Remove Event::notify_one() and Event::notify_all().
- Add Event::notify_relaxed() and Event::notify_additional_relaxed().
- Dropped notified EventListener now notifies one or one additional listener.
Open source →
1.2.0 25 May 2020
Release notes
- Add Event::notify_additional().
Open source →
1.1.2 25 May 2020
Release notes
- Change a Relaxed load to Acquire load.
Open source →
1.1.1 25 May 2020
Release notes
- Fix a bug in EventListener::wait_timeout().
Open source →
1.1.0 24 May 2020
Release notes
- Add EventListener::notify().
Open source →
1.0.1 20 May 2020
Release notes
- Reduce the complexity of notify_all() from O(n) to amortized O(1).
- Fix a bug where entries were notified in wrong order.
- Add tests.
Open source →
1.0.0 16 May 2020
Release notes
- Initial version.
Open source →

event-listener

What this package is like to depend on

Release timeline

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