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ncps

Use the ncps proxy cache to serve the nix store between machines in your network

Utility

ncps is a high-performance proxy server that accelerates Nix dependency retrieval across your local network by caching and serving packages locally.

Usage

inventory.instances = {
  ncps = {
    roles.server.machines."my-nas".settings = {
      cache.dataPath = "/srv/nas/var/lib/ncps";

        upstream = {
            caches = [
            "https://cache.nixos.org"
            "https://nix-community.cachix.org"
            "https://nixpkgs-unfree.cachix.org"
            "https://nix-gaming.cachix.org"
            "https://cuda-maintainers.cachix.org"
          ];

          publicKeys = [
            "cache.nixos.org-1:6NCHdD59X431o0gWypbMrAURkbJ16ZPMQFGspcDShjY="
            "nix-community.cachix.org-1:mB9FSh9qf2dCimDSUo8Zy7bkq5CX+/rkCWyvRCYg3Fs="
            "nixpkgs-unfree.cachix.org-1:hqvoInulhbV4nJ9yJOEr+4wxhDV4xq2d1DK7S6Nj6rs="
            "nix-gaming.cachix.org-1:nbjlureqMbRAxR1gJ/f3hxemL9svXaZF/Ees8vCUUs4="
            "cuda-maintainers.cachix.org-1:0dq3bujKpuEPMCX6U4WylrUDZ9JyUG0VpVZa7CNfq5E="
          ];
      };
    }
    roles.client.machines."client".settings = {};
  };
};

Here my-nas is configured as the ncps proxy-cache, intercepting all substitution requests from client, searches binary caches for the requested package and download and serves it if found.

The advantage of this setup over a traditional binary cache is that all retrieved packages are stored on my-nas, ready to serve other machines in your clan.

Roles

The ncps service has the following roles:

  • client
  • server

The client role has no configuration

Options for the server role

caches

Binary caches to add as upstream to ncps.

Type: list of string

Default:

[
  "https://cache.nixos.org"
  "https://nix-community.cachix.org"
]

Declared in: clanServices/ncps/default.nix

dataPath

The local directory for storing configuration and cached store paths

Type: string

Default:

"/var/lib/ncps"

Declared in: clanServices/ncps/default.nix

port

The port on which to host the ncps server

Type: signed integer

Default:

8501

Declared in: clanServices/ncps/default.nix

publicKeys

Public keys to add as upstream to ncps.

Type: list of string

Default:

[
  "cache.nixos.org-1:6NCHdD59X431o0gWypbMrAURkbJ16ZPMQFGspcDShjY="
  "nix-community.cachix.org-1:mB9FSh9qf2dCimDSUo8Zy7bkq5CX+/rkCWyvRCYg3Fs="
]

Declared in: clanServices/ncps/default.nix