these 2 derivations will be built:
  /nix/store/hbdnb4ydv11gk20a7p5p5yp55f56q2yr-devshell-dir.drv
  /nix/store/rbsxzvwjkkdj92a9ns665vaym1588fhk-devshell.drv
this path will be fetched (222.1 MiB download, 634.9 MiB unpacked):
  /nix/store/9mckxfn8npw4mrrkyp2m0vp8y76qp0n4-dart-3.13.0