mediawiki/tools/train-dev lacks CI configuration, we should add some :)
https://gerrit.wikimedia.org/g/mediawiki/tools/train-dev/
https://gerrit.wikimedia.org/r/q/project:mediawiki/tools/train-dev
That seems to require booting a VM, Timo recently crafted a job that relies on QEmu and that might be an inspiration T250808
For shell scripts, we can add the shellcheck linter. SRE is adding it to operations/puppet ( T254480 ) and we could use a generic image/script for CI T148494
Conclusion
Starting with just shellcheck and flake8.