feat(bundlers)!: Export deb, rpm and AppImage bundlers

- All logic is contained in a new `./bundlers/default.nix` module
- Add a `bundlers` `perSystem` output
- Export `deb` and `rpm` bundlers from our fork of `juliosueiras-nix/nix-utils`
  (used by `NixOS/bundlers`, which we originally used)
- Export the `AppImage` bundler from `ralismark/nix-appimage`

Author: reo101

bundlers/default.nix

@@ -0,0 +1,80 @@
+{
+  lib,
+  flake-parts-lib,
+  inputs,
+  ...
+}:
+{
+  imports = [
+    (flake-parts-lib.mkTransposedPerSystemModule {
+      name = "bundlers";
+      option = lib.mkOption {
+        type = lib.types.lazyAttrsOf (lib.types.functionTo lib.types.package);
+        default = { };
+      };
+      file = ./flake.nix;
+    })
+  ];
+
+  perSystem =
+    {
+      pkgs,
+      inputs',
+      config,
+      ...
+    }:
+    let
+      nfpmConfig =
+        pkg:
+        pkgs.writeText "${pkg.pname}-nfpm-config.yaml" (
+          builtins.toJSON {
+            name = pkg.pname;
+            inherit (pkg)
+              version
+              ;
+            inherit (pkg.meta)
+              homepage
+              description
+              ;
+            license = pkg.meta.license.spdxId or null;
+            contents = [
+              {
+                src = lib.getExe pkg;
+                dst = "/usr/bin/${pkg.meta.mainProgram or (lib.getName pkg)}";
+              }
+            ];
+          }
+        );
+
+      installerFor =
+        packager: pkg:
+        pkgs.runCommand "${pkg.pname}-${packager}-pkg" { } ''
+          mkdir -p "$out"
+          cd "$out"
+          ${lib.getExe pkgs.nfpm} package \
+            --config ${nfpmConfig pkg} \
+            --packager ${packager} \
+            --target "$out"
+        '';
+
+      installers = [
+        "deb"       # Debian/Ubuntu
+        "rpm"       # Fedora/RHEL/SUSE
+        "apk"       # Alpine
+        "archlinux" # Arch
+      ];
+
+      nfpmBundlers = lib.pipe installers [
+        (lib.map (i: {
+          name = "to${lib.toUpper (lib.substring 0 1 i)}${lib.substring 1 (-1) i}";
+          value = installerFor i;
+        }))
+        lib.listToAttrs
+      ];
+    in
+    {
+      bundlers = {
+        toAppimage = inputs'.nix-appimage.bundlers.default;
+      } // nfpmBundlers;
+    };
+}

flake.lock

@@ -229,15 +229,6 @@
       };
     };
 
-    nix-bundlers = {
-      url = "github:NixOS/bundlers";
-      inputs.nixpkgs.follows = "nixpkgs";
-      # TODO: re-add when CI's `nix` starts supporting transitive overrides
-      # inputs.nix-utils.inputs.nixpkgs.follows = "nixpkgs";
-      # inputs.nix-utils.inputs.flake-utils.follows = "flake-utils";
-      # inputs.nix-bundle.inputs.utils.follows = "flake-utils";
-    };
-
     nix-appimage = {
       url = "github:ralismark/nix-appimage";
       inputs.nixpkgs.follows = "nixpkgs";
@@ -263,6 +254,7 @@
         ./modules
         ./packages
         ./shells
+        ./bundlers
       ];
       systems = [
         "x86_64-linux"