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Examples

• Set the nixpkgs flake identifier to a specific branch of Nixpkgs:

  # nix registry add nixpkgs github:NixOS/nixpkgs/nixos-20.03
  

• Pin nixpkgs to a specific revision:

  # nix registry add nixpkgs github:NixOS/nixpkgs/925b70cd964ceaedee26fde9b19cc4c4f081196a
  

• Add an entry that redirects a specific branch of nixpkgs to another fork:

  # nix registry add nixpkgs/nixos-20.03 ~/Dev/nixpkgs
  

• Add nixpkgs pointing to github:nixos/nixpkgs to your custom flake registry:

  nix registry add --registry ./custom-flake-registry.json nixpkgs github:nixos/nixpkgs
  

Description

This command adds an entry to the user registry that maps flake reference from-url to flake reference to-url, where from-url must be a shorthand like 'nixpkgs' or 'nixpkgs/nixos-20.03'. If an entry for from-url already exists, it is overwritten.

Entries can be removed using nix registry remove.

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