# nix repl > Start an interactive environment for evaluating Nix expressions. > See for a description of the Nix expression language. > More information: . - Start an interactive environment for evaluating Nix expressions: `nix repl` - Load all packages from a flake (e.g. `nixpkgs`) into scope: `:lf {{nixpkgs}}` - Build a package from an expression: `:b {{expression}}` - Start a shell with package from the expression available: `:u {{expression}}` - Start a shell with dependencies of the package from the expression available: `:s {{expression}}`