The Good Research Code Handbook (goodresearch.dev)

This is really well done! A summary of the best practices for organizing research code, with lots of hands-on examples (Python).

Here is a copy-paste of the TOC:

   LESSONS:
   - Set up your project
   - Keep things tidy
   - Write decoupled code
   - Test your code
   - Document your code
   - Document your project
   - Make it social
   - Sample project