MarsSeed [1] filed a deletion request for java-gcj-compat [2]: Dead package from 2018. Source unavailable. And this does not seem to actually have ever provided the 'java- runtime' and the 'java-environment'. It was meant to be an open-source alternative but not a drop-in replacement. It has long been discontinued by upstream. Nowadays the Java runtime and SDK are open-source. [1] https://aur.archlinux.org/account/MarsSeed/ [2] https://aur.archlinux.org/pkgbase/java-gcj-compat/