Author: Bob Jacobsen
Keywords: JMRI technical code road map

# JMRI: Technology Road Map

This page is the road map for JMRI's future development, including changes to our use of Java technologies. It is maintained and updated through continuing discussion on the jmri-developers mailing list.

There's also a page containing the history, particularly the saga of how we moved forward to Java 1.6 and Java 8 across a series of platform-related changes.

## JMRI Releases

This section describes the history and (notional) plans for JMRI releases in the future.

Release | Description | Date | JRE | JDK
3.11.* | Development series |  | 1.6 | 8
4.0 | Production version, culmination of 3.11.* series | July 2015 | 8 | 8
4.2 | Production version, culmination of 4.1.* series | December 2015 | 8 | 8
... | ... | ... | 8 | 8
4.22 | Production version, culmination of Fall 2020 series | February 2021 | 8 | 8
4.24 | Production version, culmination of Spring 2021 series | July 2021 | 8 | 8
4.26 | Production version, culmination of Fall 2021 series | January 2022 | 8 | 8
5.0 | Production version, culmination of Spring 2022 series | June 2022 | 11 | 11
5.2 | Production version, culmination of Fall 2022 series | Jan 2023 | 11 | 11
5.4 | Production version, culmination of Spring 2023 series | June 2023 | 11 | 11
5.6 | Production version, culmination of Fall 2023 series | Jan 2024 | 11 | 11
5.8 | Production version, culmination of Spring 2024 series | June 2024 | 11 | 11
5.10 | Production version, culmination of Fall 2024 series | Jan 2025 | 11 required 17 recommended | 11 or later
5.12 | Production version, culmination of Spring 2025 series | June 2025 | 11 required 17 recommended | 11 or later
(Intended) 5.14 | Production version, culmination of Fall 2025 series | December 2025 | 11 required 17 recommended | 11 or later
(Intended) 5.16 | Production version, culmination of Spring 2026 series | June 2026 | 11 required 21 recommended | 11 or later
(Intended) 5.18 | Production version, culmination of Fall 2026 series | December 2026 | 11 required 21 recommended | 11 or later

### Java and JMRI

The 4.1.* series of test releases in Fall 2015 started the requirement for Java 8. This continued through the following release series. Java 8 continued to be the requirement through the Fall of 2021.

The next long-term-support (LTS) Java release after Java 8 is Java 11 from Fall of 2018. Oracle has aligned their Java and the OpenJDK from that point

In Spring 2022 the Java version required by JMRI moved forward, making JMRI 4.27.1 the last JMRI version running on Java 8.
Newer development releases 4.99.x culminated in the June 2022 production releases requiring Java 11 and therefore being called JMRI 5.0.

Java 11's free support by Oracle ended in September 2023.

Java 17 in 2021 was the LTS release after Java 11. Java 17's free support from Oracle runs through September 2026; after that, there won't be security updates and bug fixes to Java 17.

Starting with the JMRI 5.9.* development series, Java 11 is still supported by JMRI but Java 17 is recommended. We recommend Java 17 to move the user installations forward for eventual future migration, because Java 17 is still getting security updates, and because it's easier to install Java 17 on some OSs.

Java 21 in 2023 was the LTS release after Java 17.

After validation testing, we started recommending Java 21 for use with JMRI 5.15.1 in December 2025. That JMRI release will continue to be compatible with Java 11.

Following Java 21, the next Java LTS release was Java 25 in September 2025. Work on validating that for use with JMRI is proceeding.

For more information on compatibility, see the compatibility discussion.

#### Java Release and Operating System Support

More information on Java releases and the operating systems that support them can be found here.

Java installers are now available from multiple sources. Our Java installer page lists a number of them.