nix-pin-deps: GC-anchor a Nix build's dependencies -------------------------------------------------- When a Nix build fails for lack of disk space and a `nix-collect-garbage` is needed to make disk space available, `nix-collect-garbage` will unhelpfully delete the successfully-built dependencies of the derivation that failed because they are are not yet gc-anchored, because the build failed. This tool solves this problem: `nix-pin-deps /nix/store/...-foo.drv foo-deps` will create gc-anchors in foo-deps/ for all of the dependencies of foo.drv that exist in the nix store, keeping partial build progress safe from `nix-collect-garbage`.