Assembly Line

JDK

JDK main-line development https://openjdk.org/projects/jdk

JDK is an open-source programming language project on GitHub under the GPL-2.0 license (strong copyleft), with 23k stars. It is built with LLVM project. Its last push was today.

Stars
23k
License
GPL-2.0
Activity
Active

Code on GitHub

Judgement

What it is
Developer tool
What it does
The main-line development repository of OpenJDK, the reference implementation of the Java platform and JVM.
Adopt it when
You work on the JDK itself; most teams should install a built distribution such as Temurin.
Watch out
Main-line code is unreleased; production use should be on a supported LTS build.
Ready for
Production-ready
Runs as
Command line
Built with
Java and C++
How established
Established: started 8 years ago, no tagged release yet.
What the license allows
Use inside your business is unrestricted, but anything you distribute that includes it must be released under the same license.

Judged on 2026-11-03 from the project's README and GitHub data. The license and age lines are worked out directly.

Built from

LLVM project

Follow it down: JDK → LLVM project → runs on a microchip

How compilers were built, back to punched paper tape

Built on JDK: 151 projects

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    Framework or platform Production-ready A Chinese enterprise Java team wants to cut repetitive CRUD and workflow work.

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    ★ 40k GPL-3.0 Java Active, pushed today
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    ★ 32k Apache-2.0 Java Active, pushed today
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    Complete system Production-ready You need Airflow-class orchestration but want YAML flows, any language, and a UI non-Python people can use.

    ★ 30k Apache-2.0 Java Active, pushed today
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    ★ 30k Apache-2.0 Java Active, pushed 4 days ago
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    libGDX libgdx

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  12. 12
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    ★ 25k Apache-2.0 Java Active, pushed today
  13. 13
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  14. 14
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    ★ 17k Apache-2.0 Java Active, pushed today
  15. 15
    Zipkin openzipkin

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    ★ 17k Apache-2.0 Java Active, pushed 3 months ago
  16. 16
    Neo4j neo4j

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    ★ 17k GPL-3.0 Java Active, pushed 11 days ago
  17. 17
    TigerBeetle tigerbeetle

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  19. 19
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Open-source alternatives to JDK

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    Developer tool Production-ready You build Android apps or JVM services and want a more concise, null-safe alternative to Java.

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Stars, license and activity come from GitHub and refresh on a rolling hourly schedule. The project's own description is quoted as written.