{
  description = "horizon-advance";

  nixConfig = {
    extra-substituters = "https://horizon.cachix.org";
    extra-trusted-public-keys = "horizon.cachix.org-1:MeEEDRhRZTgv/FFGCv3479/dmJDfJ82G6kfUDxMSAw0=";
  };

  inputs = {
    horizon-core.url = "git+https://gitlab.horizon-haskell.net/package-sets/horizon-core?ref=lts/ghc-9.6.x";
    flake-utils.url = "github:numtide/flake-utils";
    nixpkgs.url = "github:nixos/nixpkgs/nixos-unstable";
  };

  outputs =
    inputs@
    { self
    , flake-utils
    , horizon-core
    , nixpkgs
    , ...
    }:
    flake-utils.lib.eachSystem [ "aarch64-darwin" "x86_64-darwin" "x86_64-linux" ] (system:
    let
      pkgs = import nixpkgs { inherit system; config.allowUnfree = true; };
    in
    with pkgs.lib;
    let
      overrides = composeManyExtensions [
        (import ./overlay.nix { inherit pkgs; })
        (import ./configuration.nix { inherit pkgs; })
      ];

      legacyPackages = horizon-core.legacyPackages.${system}.extend overrides;

      packages = filterAttrs (_: isDerivation) legacyPackages;

    in
    {
      inherit legacyPackages;
      inherit packages;
    });
}