Searching packages

There are numerous approaches available for searching substrings within both package names and package descriptions in nixpkgs.

Using search.nixos.org website

There is a web service to search with

channel branches

• Nix packages at search.nixos.org/packages
• NixOS options at search.nixos.org/options

flakes

• packages at search.nixos.org/flakes?type=packages
• options at search.nixos.org/flakes?type=options

pros

• easy to use
• allows filters
• nice GUI in browser
• browser extensions possible (like @nixpgs as search engine in Firefox)

cons

• always requires Internet connection

Using the nix search command

While this command requires flakes, you can use it to search for a package. It may be slow the first time, but further runs will use cached results.

nix search nixpkgs firefox

pros

• fast
• possible offline usage

cons

• requires disk space for caching
• quite long command

Using the nix-env command

It's possible to search for a package using nix-env -qaP

pros

• works offline

cons

• it's very slow and requires a lot of memory

Using the nix repl environment

With the read–eval–print loop (REPL) of nix you can browse packages interactively.

Starting the nix repl

nix repl

Welcome to Nix 2.18.2. Type :? for help.

nix-repl>

Loading the repository for nixpkgs

nix-repl>

nix-repl> :load <nixpkgs>
Added 21181 variables.

Type the first letters of a package

nix-repl> neo

Press Tab ↹ key for auto completion

Reverse search: searching which package provides a file

There are third party programs that make it easier to determine which package you need to install in order to obtain a specific file or program.

These are most commonly used, and require you to create an index on your computer before you can search for a package:

• nix-community/nix-index
• replit/rippkgs

These are online tools which search an index someone else keeps up to date:

• peterldowns/nix-search-cli: nix-search -p theBinaryIWantToInstall to search the search.nixos.org elasticsearch index.