Where might implementation guides live?

[crertel]

Problem

As a (semi-hypothetical) hopeful contributor new to the codebase, I would like to be able to add features (or work on them).

Unfortunately, learning where to make changes requires talking to people or reading a lot of code:

• HACKING.md points at building.md, which is great but doesn't really give a rough map.
• CONTRIBUTING.md is good for basic workflows, but doesn't really provide

Proposal

Under the maintainers directory, we have a file (HITCHHIKERS_GUIDE.md or somesuch) that gives rough locations for things that people might want to hack on ("Want to add a primop? Go here and add it, and got here and add tests.", "Want to debug how a command-line flag is handled? Go here"), etc.

Does that seem doable? Sort of a foraging guide for contributors.

Checklist

• checked latest Determinate Nix manual (source)
• checked open bug issues and pull requests for possible duplicates