| First, and most important, Jetty 9.x is now at End of Community Support. See the announcement at https://github.com/eclipse/jetty.project/issues/7958 we should be using Jetty 10+ now. For Logback, you cannot use Logback 1.3.x on Jetty 9.x That's because it requires Servlet 4.0.1, which is available on Jetty 10+ (not Jetty 9) For Jetty 9.x you should stick with Logback 1.2.x, but that also means you are stuck with all of the Hanging / Blocked Thread / Async / 100% CPU bugs that logback hasn't fixed in Logback 1.2.x (many were fixed in Logback 1.3.x, and a lot more were fixed in Logback 1.4.x). The breakdown of Logback to Servlet to Jetty
| Logback |
Servlet |
Namespace |
Jetty |
| 1.2.x |
Servlet 3.1.x |
javax.servlet |
Jetty 9.x |
| 1.3.x |
Servlet 4.0.x |
javax.servlet |
Jetty 10.x |
| 1.4.x |
Servlet 5.0.x |
jakarta.servlet |
Jetty 11.x |
|