Read Eval Print Loop

Updated: September 28, 2024

REPL is an interactive shell for evaluating Nix expressions.

REPL can load in Nixpkgs and Flakes. And you can then evaluate Nix expressions.
It is great for determining if a feature is working or not, that is, searchable.

nix repl

:?                # help
:a                # add attrs from result set to scope
:b                # build
:bl               # build deriv, create GC roots in working dir
:e                # edit
:l                # load
:lf               # load flake
:r                # reload
:sh               # build deps of deriv, then start nix-shell
:t                # describe result of eval
:u                # build deriv, then start nix-shell
:q                # quit

:doc              # show doc of a builtin funtion
:log              # show logs for a deriv