Specifically we (SimRe/EPP/Oomph) have a serious problem that Temurin has not been able to produce a Windows Aarch64 Java 25 JDK for long time. It's blocked by TCK tests apparently: https://github.com/adoptium/aqa-tests/issues/6623 This prevents JustJ from building JRE's for that version and architecture. It's an ongoing concern in the general community as raised also in this issue: https://github.com/adoptium/adoptium-support/issues/1402 In this comment on that issue https://github.com/adoptium/adoptium-support/issues/1402#issuecomment-4700355336 there is the assertion that > the MSFT Build of OpenJDK is licensed no differently to Eclipse Temurin binaries I imagine the JDK has the same license terms as OpenJDK. JustJ has approval for using OpenJDK: > Originally approval was limited to the latest release available via https://jdk.java.net/, but now releases available via https://adoptium.net/ are also approved. This has the major advantage that Long Term Support (LTS) versions are now available. I did verify that a link to a Microsoft Java 25.0.3 JDK for Windows Aarch64 is indeed a drop-in replacement for the missing Temurin link. As such I would like to request permission for JustJ to temporarily use a Microsoft JDK while the corresponding Termurin JDK is unavailable.