By default haskell.nix cabalProject functions run cabal configure with --enable-tests and --enable-benchmarks. This is good when you are working on a project as it means your tests and benchmarks are in the package `components`. The `tools` functions (and `shellFor` `tools` arg) return `components.exes.${toolName}` and while it is possible to access the other components via the `project` and `package` properties of tool component. In some cases the benchmarks and tests can have problematic constraints that cause problems building other components. Disabling the tests and benchmarks by default when building `tools` should reduce the these issues.