Haven't tried using with IDA. Documentation says Qt version needs to match your IDA's Qt, so include both qt4 and qt5 variants as basic coverage.

Not sure how to include these (cc #27604) but created a derivation for running the "snowman-tests" test suite to check the build Snowman:

Commit
Branch

If nothing else they're available in case anyone is interested :). LMK if it makes sense to include those in this PR otherwise I'll wait on discussion in #27604.

Not sure how to include these (cc #27604)

Awesome!

Basically you have a withTests :: AttrsOf Derivation -> Derivation -> Derivation which takes an attrset of tests (name to derivation to run) and the actual derivation and outputs a derivation that depends on all tests to build.
If you do something like

{ pkgs, lib … }:
let
  # stub, FIXME(Profpatsch)
  withTests = flip lib.const;

  snowman = …;

  tests = {
    snowman-testsuite = pkgs.callPackage ./tests.nix { inherit snowman; };
  };

in withTests tests snowman

I will pick it up once the tests get merged.