Comment by mikepurvis

As someone 8 months into a major Nix packaging effort (1200 package definitions, mostly auto-generated), this is 1000% the most significant issue. Reading the pills can get you the first little bit, like the difference between derivation and mkDerivation, but so much later stuff is just completely undiscoverable and inconsistent, like the fact that overrideAttrs may subtly not do what you want if it's a Python package since you have to use overridePythonAttrs instead, but the corresponding function for other builders (eg overrideBazelAttrs) doesn't exist.