Mix release became the offical way to release an Elixir project some years ago. Distillery had been the previous one.
Here are the steps needed to move across:
1. Move any config that uses environment variables into runtime exs.
2. Add a release section in your mix.exs
3. If you were using rel/config.exs to copy files into the release add this to a custom function in the mix.exs step
4. Remove distillery from your mix.exs and clean up the lock file.
5. Adjust your build process to call mix release instead of distillery.
This requires a lot of careful testing!
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