Please suggest CI service that can run Java/Scala builds with tests on non-x86 architectures: ARM, PowerPC etc. Maven (or Sbt) integration is required. Free option for OSS projects (like in Travis-CI or Shippable) is highly desirable.
Service or software? For software i've written something that is cross platform.
http://linci.tp23.org/ is written basically in bash. Its reuses existing Linux tools to cobble together a CI server.
ssh for remoting,
tsp for task scheduling,
cron for timers,
awk to define jobs and the CLI to execute them.
mailx for notifications.
I run it on x86 and raspberry pi (ARM), I think it will run on anything for which you can find a Debian based Linux distro. Linux only.
Plugins are sets of env variables: you define an environment for a build e.g. you could define
java9 with different
MAVEN_HOME and to exec maven linci can call maven's cli. It does not need a plugin for each tool provided the tool has a CLI.
UI is cli/terminal, with bash_completion.
vcs triggers, i.e. run build on submit, use the vvcs buidlint hooks, git hooks, svn perforce triggers and bzr python hook.
Webhooks use a nodejs server, but would be trivial to write webhooks on a different platform.