Store path

The directory used by Nix to store store paths (including derivations).

From here, you can verify that both the programs are indeed in $PATH as indicated by the “bin” directory in their respective store paths:

Note that this is the same path used by both nix build and nix shell. Each specific package is uniquely identified by their Store path; changing any part of its build recipe (including dependencies), changes that path. Hence, nix is reproducible.

These symlinks, ultimately, point to the package Store path outputs under the Nix Store, viz.:

What is a Nix “package”? Technically, a Nix package is a special Store path built using instructions from a Derivation, both of which reside in the Nix Store. To see what is contained by the cowsay package, look inside its Store path. To get the store path for a package (here, cowsay), run nix build as follows:

[!info] Nix Store & Store Paths /nix/store is a special directory representing the Nix Store. The paths inside /nix/store are known as Store path. Nix fundamentally is, in large part, about manipulating these store paths in a pure and reproducible fashion; Derivation are “recipes” that does this manipulation, and they too live in the Nix Store.