The reliable, generic, fast and flexible logging framework for Java.
The reliable, generic, fast and flexible logging framework for Java.
Thank you for your interest in logback, the reliable, generic, fast and flexible logging library for Java.
The Logback documentation can be found on the project web-site.
The 1.6.x series is a direct descendant of and a drop-in replacement for the 1.5.x series which is a direct descendant of and a drop-in replacement for the 1.4.x series. The 1.6.x differs from the 1.4.x series by the relocation of the logback-access module which was moved to its own separate github repository.
Here is a summary of 1.5.x dependencies:
Logback version github branch SLF4J version JDK at runtime JDK during build Enterprise Edition (optional) 1.6.x master 2.0.x 11 17 Jakarta EE (jakarta.* namespace)Version 1.6.x requires Java 17 to compile and build.
More details on building logback is documented at:
https://logback.qos.ch/setup.html#ide
In case of problems please do not hesitate to post on github discussions forum. Please do not directly e-mail logback developers.
For urgent issues do not hesitate to champion a release. In principle, most championed issues are solved within 3 business days followed up by a release.
If you are interested in improving logback, that is great! The logback community looks forward to your contribution. Please follow this process:
Fork qos-ch/logback. Ideally, create a new branch from your fork for your contribution to make it easier to merge your changes back.
Make the effort to explain the aim of your proposed change.
Make your changes on the branch you hopefully created in Step 2. Be sure that your code passes existing unit tests.
Please add unit tests for your work if appropriate. It usually is.
Push your changes to your fork/branch in GitHub. Don't push it to your master! If you do it will make it harder to submit new changes later.
Submit a pull request to logback from your commit page on GitHub. All commits must have signed off by the contributor attesting to Developer Certificate of Origin (DCO). Commits without sign off will be automatically rejected by the DCO GitHub check application.
Do not forget to explain your proposed changes.
Upgrade Logback 1.6.3 fail to start spring boot application
Regression: ${...} property substitution no longer works for scan attribute in Logback 1.5.27+ (works in 1.5.21)
Please backport remaining 2026 security fixes to the 1.3.x series (precedent: 1.3.16 / CVE-2025-11226)
Security report submitted via email on 2026-06-30 — awaiting acknowledgment
fix CVE-2026-1225 to 1.3.x branch
Add support for OTLP
Logback can no longer monitor not-yet-existing included property files
All threads blocked
<condition> placed inside <if> is silently ignored, produces misleading "Janino not found" error