Seems like a reasonably standard Rails app, and they are kind enough to already have a Dockerfile, compose file, and instructions for it: https://github.com/maybe-finance/maybe/blob/v0.5.0/docs/host...

Ironically, as documentation for humans these files are good; as a separate signal that Cursor wrote a finance tracking app is also helpful https://github.com/maybe-finance/maybe/blob/v0.5.0/.cursor/r...