Monix: Version 2.0-RC10 Released

This release adds some useful extension methods for Scheduler and Callback, while optimizing and making safer some Task operations, like gatherUnordered, ‘chooseFirstOfList’ and create. On Observable it also changes how onOverflow behaves when specified in an OverflowStrategy. This will be a breaking, but easy to fix change.

Release RC10 is the last release before 2.0, scheduled for September 1st (promise, cross my heart and hope to …).

BUG WARNING: this release contains a critical bug issue. Upgrade to the latest version as soon as possible.

See the published API Documentation.


  • Issue #200: Add an executeNow extension method for Scheduler, taking a by-name callback, as initializing Runnable instances is too annoying
  • Issue #201: Fixes and optimizes Task.gatherUnordered - as an edge-case, it wasn’t stack safe and it has been optimized to be more efficient
  • Issue #202: Added asyncOnSuccess and asyncOnError as extension methods for Callback and made Task.create safe by forcing an asynchronous boundary when calling the callback (onSuccess/onError); also optimizes Task.chooseFirstOfList and TestScheduler
  • Issue #203: Changed the onOverflow function signature for OverflowStrategy types supporting it - it can now return an Option and if it returns None, then we don’t signal any messages downstream, thus making it easier to just log that overflow happened without extra tricks