A workaround for me was to keep the source code, start again from the beginning from the first step and then paste the source code. But maybe there is a simpler way?
Hey @amoilanen, unfortunately that’s currently the only way to “upgrade” a buildpack yourself.
Let me know if you’d like me to upgrade any of your old repos for you.
EDIT on 2026-01-06:
We now support updating language version through the CLI.