SBT should work fine with jdk-1.8*.
Thanks for reporting, fixed in sbt-0.13.11 commit cc12259f2c6c10bfdb780156b1f0e31008749f1e Author: Mark Wright <gienah@gentoo.org> Date: Wed Feb 24 00:44:10 2016 +1100 dev-java/sbt: Bump to 0.13.11, allow building with jdk 1.8. Thanks to Christian Strahl for the bump request 562904 and Pavel Kozlov for reporting 560810 requesting allowing building with jdk 1.8. Gentoo-Bug: https://bugs.gentoo.org/show_bug.cgi?id=562904 Gentoo-Bug: https://bugs.gentoo.org/show_bug.cgi?id=560810