nix-instantiate instantiate store expressions from Nix expressions nix-instantiate --parse-only --eval-only files The command nix-instantiate generates (low-level) store expressions from (high-level) Nix expressions. It loads and evaluates the Nix expressions in each of files. Each top-level expression should evaluate to a derivation, a list of derivations, or a set of derivations. The paths of the resulting store expressions are printed on standard output. This command is generally used for testing Nix expression before they are used with nix-env. --parse-only Just parse the input files, and print their abstract syntax trees on standard output in ATerm format. --eval-only Just parse and evaluate the input files, and print the resulting values on standard output. No instantiation of store expressions takes place. $ nix-instantiate gcc.nix (instantiate) /nix/store/468abdcb93aa22bb721142615b97698b-d-gcc-3.3.2.store $ nix-store -r $(nix-instantiate gcc.nix) (build) $ nix-store -r $(nix-instantiate gcc.nix) (print output path) /nix/store/9afa718cddfdfe94b5b9303d0430ceb1-gcc-3.3.2 $ ls -l /nix/store/9afa718cddfdfe94b5b9303d0430ceb1-gcc-3.3.2 dr-xr-xr-x 2 eelco users 360 2003-12-01 16:12 bin dr-xr-xr-x 3 eelco users 72 2003-12-01 16:12 include ...