[benreesman]

So a dev shell as consumed by a flake is typically just a derivation. And typically the most important thing in that derivation is ‘buildInputs’, which is just a list of ‘pkgs.thingIWant’. It’s not uncommon to hook other “phases” of the derivation, which are (oversimplified) just little shell scripts that run in some order (‘configurePhase’ before ‘installPhase’) and typically expressed using the nifty “” syntax. For example if Nix is like stuffing paths into a Makefile that you want to use in your dev shell, you might put that in installPhase. Protip: a Nix “package” (derivation) evaluated in a string context (foo = “${pkgs.gcc}”;) gives you a path to where the thing lives in /nix/store.