{
  description = "logos-delivery nim build flake";

  nixConfig = {
    extra-substituters = [ "https://nix-cache.status.im/" ];
    extra-trusted-public-keys = [
      "nix-cache.status.im-1:x/93lOfLU+duPplwMSBR+OlY4+mo+dCN7n0mr4oPwgY="
    ];
  };

  inputs = {
    # Pinning the commit to use same commit across different projects.
    # A commit from nixpkgs 25.11 release: https://github.com/NixOS/nixpkgs/tree/release-25.11
    # Includes the fetchCargoVendor crates.io CDN fix (nixpkgs 0fb82de3).
    nixpkgs.url = "github:NixOS/nixpkgs?rev=535f3e6942cb1cead3929c604320d3db54b542b9";

    rust-overlay = {
      url = "github:oxalica/rust-overlay";
      inputs.nixpkgs.follows = "nixpkgs";
    };

    # Zerokit v2.0.2; keep rev in sync with the vendor/zerokit submodule.
    zerokit = {
      url = "github:vacp2p/zerokit/5e64cb8822bee65eed6cf459f95ae72b80c6ba63";
      inputs.nixpkgs.follows = "nixpkgs";
    };
  };

  outputs = { self, nixpkgs, rust-overlay, zerokit }:
    let
      systems = [
        "x86_64-linux" "aarch64-linux"
        "x86_64-darwin" "aarch64-darwin"
        "x86_64-windows"
      ];

      forAllSystems = nixpkgs.lib.genAttrs systems;

      lib = nixpkgs.lib;

      # Single source of truth for the semver: the `version` field of
      # logos_delivery.nimble. Kept in sync with git tags by the version-check CI.
      nimbleVersion =
        let line = lib.findFirst (l: lib.hasPrefix "version = " l)
                     "version = \"unknown\""
                     (lib.splitString "\n" (builtins.readFile ./logos_delivery.nimble));
        in lib.removeSuffix "\"" (lib.removePrefix "version = \"" line);

      # A flake sandbox has no .git, so `git describe` is impossible; the
      # commit comes from the flake metadata instead.
      shortRev = self.shortRev or self.dirtyShortRev or "dirty";

      nimbleOverlay = final: prev: {
        nimble = prev.nimble.overrideAttrs (_: {
          version = "0.22.3";
          src = prev.fetchFromGitHub {
            owner = "nim-lang";
            repo  = "nimble";
            rev   = "v0.22.3";
            sha256 = "sha256-f7DYpRGVUeSi6basK1lfu5AxZpMFOSJ3oYsy+urYErg=";
          };
        });
      };

      pkgsFor = system: import nixpkgs {
        inherit system;
        overlays = [ (import rust-overlay) nimbleOverlay ];
      };
    in {
      packages = forAllSystems (system:
        let
          pkgs = pkgsFor system;

          zerokitRln = import ./nix/zerokit.nix { inherit zerokit system; };

          liblogosdelivery = pkgs.callPackage ./nix/default.nix {
            inherit pkgs;
            src = ./.;
            inherit zerokitRln;
            gitVersion = "v${nimbleVersion}-g${builtins.substring 0 6 shortRev}";
          };

          wakucanary = pkgs.callPackage ./nix/default.nix {
            inherit pkgs;
            src = ./.;
            targets = ["wakucanary"];
            inherit zerokitRln;
          };
        in {
          inherit liblogosdelivery wakucanary;
          # Expose librln so downstream consumers link the exact same build.
          rln = zerokitRln;
          default = liblogosdelivery;
        }
      );

      devShells = forAllSystems (system:
        let
          pkgs = pkgsFor system;
        in {
          default = pkgs.mkShell {
            nativeBuildInputs = with pkgs; [
              nim-2_2
              nimble
            ];
          };
        }
      );
    };
}