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Java repos to contribute to

OpenSrc lists 141 Java repositories with open issues for new contributors, and 71 of them are first-PR friendly. Between them they have 2,377 open good first issues and 2,122 help-wanted issues. The median welcome score is 73/100, and the best-scored right now are DependencyTrack/dependency-track, jenkinsci/jenkins and elastic/elasticsearch. Most are about Databases, Backend & APIs and Machine Learning & AI.

141 repos by best score

Filter these in the directory

DependencyTrack/dependency-track
Dependency-Track is an intelligent Component Analysis platform that allows organizations to identify and…
33good first issues+40 help wanted
- Java
- Field: Security
- Stars:4.2K
- committed 10h ago
- Apache-2.0
- CONTRIBUTING
- replies in ~16h
Score94 out of 100 contributor score, very welcomingFirst-PR friendly
jenkinsci/jenkins
Jenkins automation server
13good first issues+3 help wanted
- Java
- Field: DevOps
- Stars:26.6K
- committed 2h ago
- MIT
- CONTRIBUTING
- replies in ~16h
Score93 out of 100 contributor score, very welcomingFirst-PR friendly
elastic/elasticsearch
Free and Open Source, Distributed, RESTful Search Engine
21good first issues+75 help wanted
- Java
- Stars:78.1K
- committed just now
- CONTRIBUTING
- replies in ~1m
Score92 out of 100 contributor score, very welcomingFirst-PR friendly
cryptomator/cryptomator
Cryptomator for Windows, macOS, and Linux: Secure client-side encryption for your cloud storage, ensuring…
14good first issues
- Java
- Field: Security
- Field: DevOps
- Stars:16.2K
- committed 1d ago
- GPL-3.0
- CONTRIBUTING
- replies in ~27h
Score91 out of 100 contributor score, very welcomingFirst-PR friendly
trinodb/trino
Official repository of Trino, the distributed SQL query engine for big data, formerly known as PrestoSQL…
41good first issues
- Java
- Field: Databases
- Field: Data Science
- Stars:13.3K
- committed 2h ago
- Apache-2.0
- CONTRIBUTING
- replies in ~1h
Score89 out of 100 contributor score, very welcomingFirst-PR friendly
TeamNewPipe/NewPipe
A libre lightweight streaming front-end for Android.
49good first issues+39 help wanted
- Java
- Field: Mobile
- Field: Web Frontend
- Stars:39.8K
- committed 3d ago
- GPL-3.0
- CONTRIBUTING
- replies in ~26h
Score88 out of 100 contributor score, very welcomingFirst-PR friendly
OpenAPITools/openapi-generator
OpenAPI Generator allows generation of API client libraries (SDK generation), server stubs, documentation and…
3good first issues+52 help wanted
- Java
- Field: Backend
- Stars:26.8K
- committed 3h ago
- Apache-2.0
- CONTRIBUTING
- replies in ~23h
Score88 out of 100 contributor score, very welcomingFirst-PR friendly
quarkusio/quarkus
Quarkus: Supersonic Subatomic Java.
19good first issues+5 help wanted
- Java
- Field: DevOps
- Stars:15.9K
- committed just now
- Apache-2.0
- CONTRIBUTING
- replies in ~15h
Score88 out of 100 contributor score, very welcomingFirst-PR friendly
apache/pulsar
Apache Pulsar - distributed pub-sub messaging system
11good first issues+59 help wanted
- Java
- Stars:15.3K
- committed 1h ago
- Apache-2.0
- CONTRIBUTING
- replies in ~2d
Score87 out of 100 contributor score, very welcomingFirst-PR friendly
uyuni-project/uyuni
Open-source systems management and configuration platform
39good first issues+3 help wanted
- Java
- Field: OS
- Field: Databases
- Stars:587
- committed just now
- GPL-2.0
- CONTRIBUTING
- replies in ~2d
Score87 out of 100 contributor score, very welcomingFirst-PR friendly
kestra-io/kestra
Event Driven Orchestration & Scheduling Platform for Mission Critical Applications
46good first issues
- Java
- Field: DevOps
- Field: Data Science
- Stars:28.5K
- committed just now
- Apache-2.0
- CONTRIBUTING
- replies in ~14h
Score86 out of 100 contributor score, very welcomingFirst-PR friendly
eclipse-openj9/openj9
Eclipse OpenJ9: A Java Virtual Machine for OpenJDK that's optimized for small footprint, fast start-up, and…
17good first issues+53 help wanted
- Java
- Field: Compilers
- Field: Networking
- Stars:3.5K
- committed 4d ago
- CONTRIBUTING
- replies in ~2h
Score86 out of 100 contributor score, very welcomingFirst-PR friendly
libgdx/libgdx
Desktop/Android/HTML5/iOS Java game development framework
9good first issues+3 help wanted
- Java
- Field: Game Dev
- Field: Mobile
- Stars:25.4K
- committed 5d ago
- Apache-2.0
- CONTRIBUTING
- replies in ~9h
Score85 out of 100 contributor score, very welcomingFirst-PR friendly
terrakube-io/terrakube
Open source IaC Automation and Collaboration Software.
6good first issues+16 help wanted
- Java
- Field: DevOps
- Stars:966
- committed 3d ago
- Apache-2.0
- CONTRIBUTING
- replies in ~42m
Score85 out of 100 contributor score, very welcomingFirst-PR friendly
opensearch-project/security
🔐 Secure your cluster with TLS, numerous authentication backends, data masking, audit logging as well as…
15good first issues+37 help wanted
- Java
- Field: Security
- Field: Backend
- Stars:253
- committed 6h ago
- Apache-2.0
- CONTRIBUTING
- replies in ~2d
Score84 out of 100 contributor score, very welcomingFirst-PR friendly
Stirling-Tools/Stirling-PDF
#1 PDF Application on GitHub that lets you edit PDFs on any device anywhere
4good first issues
- Java
- Field: DevOps
- Field: Web Frontend
- Stars:93.2K
- committed just now
- CONTRIBUTING
- replies in ~9h
Score83 out of 100 contributor score, very welcomingFirst-PR friendly
logisim-evolution/logisim-evolution
Digital logic design tool and simulator
10good first issues+44 help wanted
- Java
- Stars:7.7K
- committed 1h ago
- GPL-3.0
- CONTRIBUTING
- replies in ~15h
Score83 out of 100 contributor score, very welcomingFirst-PR friendly
line/armeria
Your go-to microservice framework for any situation, from the creator of Netty et al. You can build any type…
6good first issues
- Java
- Field: Backend
- Field: Networking
- Stars:5.1K
- committed 1d ago
- Apache-2.0
- CONTRIBUTING
- replies in ~6h
Score83 out of 100 contributor score, very welcomingFirst-PR friendly
zaproxy/zaproxy
The ZAP by Checkmarx Core project
11good first issues+2 help wanted
- Java
- Field: Security
- Stars:15.8K
- committed 5d ago
- Apache-2.0
- CONTRIBUTING
- replies in ~10h
Score82 out of 100 contributor score, very welcomingFirst-PR friendly
opensearch-project/OpenSearch
🔎 Open source distributed and RESTful search engine.
68good first issues+15 help wanted
- Java
- Field: Data Science
- Stars:13.8K
- committed just now
- Apache-2.0
- CONTRIBUTING
Score81 out of 100 contributor score, very welcomingFirst-PR friendly
Graylog2/graylog2-server
Free and open log management
12good first issues
- Java
- Field: Observability
- Field: Security
- Stars:8.2K
- committed just now
- CONTRIBUTING
Score81 out of 100 contributor score, very welcomingFirst-PR friendly
SkriptLang/Skript
Skript is a Paper plugin which allows server admins to customize their server easily, but without the hassle…
30good first issues+3 help wanted
- Java
- Stars:1.3K
- committed 4w ago
- GPL-3.0
- CONTRIBUTING
- replies in ~24m
Score81 out of 100 contributor score, very welcomingFirst-PR friendly
DIGI-UW/OpenELIS-Global-2
OpenELIS Global — open-source Laboratory Information System (LIS/LIMS) for clinical and public-health labs in…
25good first issues+2 help wanted
- Java
- Field: Web Frontend
- Field: DevOps
- Stars:262
- committed just now
- MPL-2.0
- CONTRIBUTING
Score81 out of 100 contributor score, very welcomingFirst-PR friendly
MovingBlocks/Terasology
Terasology - open source voxel world
35good first issues
- Java
- Field: Game Dev
- Field: Graphics
- Stars:3.9K
- committed 2h ago
- Apache-2.0
- CONTRIBUTING
- replies in ~30d
Score80 out of 100 contributor score, very welcoming
SasanLabs/VulnerableApp
OWASP VulnerableApp Project: Break it. Scan it. Reproduce it. Benchmark against it. Improve it.
71good first issues+23 help wanted
- Java
- Field: Security
- Field: Web Frontend
- Stars:467
- committed 1h ago
- Apache-2.0
- CONTRIBUTING
Score80 out of 100 contributor score, very welcomingFirst-PR friendly
labsai/EDDI
Config-driven engine that turns JSON into production-grade AI agents. Multi-agent orchestration, 12+ LLM…
10good first issues+14 help wanted
- Java
- Field: Machine Learning
- Field: DevOps
- Stars:380
- committed just now
- Apache-2.0
- CONTRIBUTING
Score80 out of 100 contributor score, very welcomingFirst-PR friendly
PGMDev/PGM
The original PvP Game Manager for Minecraft
13good first issues+6 help wanted
- Java
- Field: Game Dev
- Stars:208
- committed 1d ago
- AGPL-3.0
- CONTRIBUTING
Score80 out of 100 contributor score, very welcomingFirst-PR friendly
apache/incubator-seata
:fire: Seata is an easy-to-use, high-performance, open source distributed transaction solution.
18good first issues
- Java
- Field: Backend
- Stars:26K
- committed 1d ago
- Apache-2.0
- CONTRIBUTING
Score79 out of 100 contributor score, very welcomingFirst-PR friendly
bazelbuild/bazel
a fast, scalable, multi-language and extensible build system
5good first issues+259 help wanted
- Java
- Stars:25.9K
- committed just now
- Apache-2.0
- CONTRIBUTING
Score79 out of 100 contributor score, very welcomingFirst-PR friendly
questdb/questdb
QuestDB is a high performance, open-source, time-series database
19good first issues+10 help wanted
- Java
- Field: Databases
- Field: Data Science
- Stars:17.4K
- committed 14h ago
- Apache-2.0
- CONTRIBUTING
- replies in ~30d
Score79 out of 100 contributor score, very welcoming

Showing 30 of 141 repos

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