From a4883480ae278c874a9a16782bf233bf70b87243 Mon Sep 17 00:00:00 2001
From: Tim Van Baak <tim.vanbaak@gmail.com>
Date: Tue, 20 Jun 2023 18:46:41 +0000
Subject: [PATCH] Add nixos module and package overlay

---
 README.md |  2 ++
 flake.nix | 55 +++++++++++++++++++++++++++++++++++--------------------
 2 files changed, 37 insertions(+), 20 deletions(-)

diff --git a/README.md b/README.md
index 20886b7..f20afb6 100644
--- a/README.md
+++ b/README.md
@@ -2,6 +2,8 @@
 
 This repo contains programs that act as `intake` feed sources.
 
+The provided NixOS module adds the default overlay to `nixpkgs`, providing each feed source program individually as well as the `intakeSources` package that provides all of them together.
+
 ## intake-rss
 
 A feed source that wraps an RSS or Atom feed.
diff --git a/flake.nix b/flake.nix
index a68e3ef..c7e863a 100644
--- a/flake.nix
+++ b/flake.nix
@@ -6,31 +6,20 @@
   outputs = { self, nixpkgs }:
   let
     system = "x86_64-linux";
-    pkgs = nixpkgs.legacyPackages.${system};
-    pypkgs = pkgs.python38Packages;
-    pythonPackage = name: path: deps: pypkgs.buildPythonPackage {
-      inherit name;
-      src = builtins.path { inherit name path; };
-      format = "pyproject";
-      propagatedBuildInputs = [ pypkgs.setuptools ] ++ deps;
-    };
   in {
-    packages.${system} = {
-      default = pkgs.symlinkJoin {
-        name = "intake-sources";
-        paths = [
-          self.packages.${system}.intake-rss
-          self.packages.${system}.intake-reddit
-          self.packages.${system}.intake-hackernews
-        ];
-      };
-      intake-rss = pythonPackage "intake-rss" ./intake-rss [ pypkgs.feedparser ];
-      intake-reddit = pythonPackage "intake-reddit" ./intake-reddit [];
-      intake-hackernews = pythonPackage "intake-hackernews" ./intake-hackernews [];
+    packages.${system} = let
+      pkgs = (import nixpkgs {
+        inherit system;
+        overlays = [ self.overlays.default ];
+      });
+    in {
+      default = pkgs.intakeSources;
+      inherit (pkgs) intake-rss intake-reddit intake-hackernews;
     };
 
     devShells.${system} = {
       python = let
+        pkgs = nixpkgs.legacyPackages.${system};
         pythonEnv = pkgs.python38.withPackages (pypkgs: with pypkgs; [ black feedparser ]);
       in pkgs.mkShell {
         packages = [ pythonEnv ];
@@ -39,6 +28,32 @@
         '';
       };
     };
+
+    overlays.default = final: prev: let
+      pythonPackage = name: path: deps: final.python38Packages.buildPythonPackage {
+        inherit name;
+        src = builtins.path { inherit name path; };
+        format = "pyproject";
+        propagatedBuildInputs = [ final.python38Packages.setuptools ] ++ deps;
+      };
+    in
+    {
+      intakeSources = final.symlinkJoin {
+        name = "intake-sources";
+        paths = [
+          final.intake-rss
+          final.intake-reddit
+          final.intake-hackernews
+        ];
+      };
+      intake-rss = pythonPackage "intake-rss" ./intake-rss [ final.python38Packages.feedparser ];
+      intake-reddit = pythonPackage "intake-reddit" ./intake-reddit [];
+      intake-hackernews = pythonPackage "intake-hackernews" ./intake-hackernews [];
+    };
+
+    nixosModules.default = {
+      nixpkgs.overlays = [ self.overlays.default ];
+    };
   };
 }