ReactiveX/RxJava

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RxJava – Reactive Extensions for the JVM – a library for composing asynchronous and event-based programs using observable sequences for the Java VM.

Stars: 48.2k
Forks: 7.6k
Open beginner issues: 0
Indexed issues: 11
Avg merge: 39m
Merged PRs (30d): 11

Dominant language: Java
License: Apache-2.0
Last GitHub push: Sep 17, 2026
Latest indexed: Sep 19, 2026
Contributing guide: Contributing guide
Code of conduct: No code of conduct
Beginner labels: No beginner labels indexed

Beginner friendly Everything

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11 issues indexed so far

4.x: Streamable operator checklist Open

4.x AI Enhancement Streamable

Difficulty 4/5 3-5 days Newbie friendliness 45/100

ReactiveX/RxJava#8299 · Opened Aug 27, 2026
4.x: FlowableBufferTest > longTimeAction() FAILED Open

4.x Test-Failures

ReactiveX/RxJava#8280 · 1 assignee · Opened Aug 10, 2026
4.x: Java target version clarification Open

4.x Discussion

Difficulty 5/5 Over a week Newbie friendliness 25/100

ReactiveX/RxJava#8089 · Opened Mar 30, 2026
4.x: Separate `TestHelper.race` uses so they can run `@Isolated` Open

4.x PR welcome Test Test-Failures

Difficulty 4/5 3-5 days Newbie friendliness 45/100

ReactiveX/RxJava#8075 · 4 comments · Opened Mar 25, 2026
Fragile window abandonment during concatMap operations; silent data loss Open

3.x 4.x Investigating

Difficulty 4/5 3-5 days Newbie friendliness 38/100

ReactiveX/RxJava#7956 · 2 comments · 1 reaction · Opened Jan 30, 2026
4.x: Cache/Replay operators to be more GC friendly Open

4.x Enhancement

Difficulty 4/5 3-5 days Newbie friendliness 45/100

ReactiveX/RxJava#7912 · 3 comments · Opened Oct 2, 2025
Feature Request: Add `Observable.usingWhen()` for resources generated by a `Publisher` Open

4.x Feature-Request

Difficulty 5/5 Over a week Newbie friendliness 30/100

ReactiveX/RxJava#7548 · 3 comments · Opened Mar 25, 2023
Feature Request: Add unfold construct to Flowable/Observable Open

4.x Feature-Request

Difficulty 5/5 Over a week Newbie friendliness 35/100

ReactiveX/RxJava#7422 · 17 comments · Opened May 26, 2022
4.x: parallel performs poorly with 10+ parallelism Open

4.x Performance

ReactiveX/RxJava#6931 · 3 comments · 2 reactions · 1 assignee · Opened Mar 11, 2020
Update wiki to reflect 4.x (tracking issue) Open

4.x Discussion Documentation PR welcome

Difficulty 5/5 Over a week Newbie friendliness 28/100

ReactiveX/RxJava#6132 · 23 comments · Opened Aug 3, 2018
4.x: Flowable missing or incorrect marbles (tracking issue) Open

4.x Documentation PR welcome

Difficulty 5/5 Over a week Newbie friendliness 25/100

ReactiveX/RxJava#5813 · 5 comments · Opened Jan 17, 2018

ReactiveX/RxJava

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