From 5cff649141adbc141274875cc16af3912561c25b Mon Sep 17 00:00:00 2001
From: Mats Rauhala <mats.rauhala@iki.fi>
Date: Mon, 15 Nov 2021 20:50:03 +0200
Subject: [PATCH] Enable flakes support

---
 flake.lock | 75 ++++++++++++++++++++++++++++++++++++++++++++++++++++++
 flake.nix  | 46 +++++++++++++++++++++++++++++++++
 shell.nix  | 43 ++++++-------------------------
 3 files changed, 129 insertions(+), 35 deletions(-)
 create mode 100644 flake.lock
 create mode 100644 flake.nix

diff --git a/flake.lock b/flake.lock
new file mode 100644
index 0000000..e46f8a3
--- /dev/null
+++ b/flake.lock
@@ -0,0 +1,75 @@
+{
+  "nodes": {
+    "easy-hls-src": {
+      "inputs": {
+        "nixpkgs": "nixpkgs"
+      },
+      "locked": {
+        "lastModified": 1636606878,
+        "narHash": "sha256-rLxYl7iYP9vQhSvVlV2uRCdgrqKDz/vN1Z8ZmA8itkM=",
+        "owner": "jkachmar",
+        "repo": "easy-hls-nix",
+        "rev": "edd5710946d46ea40810ef9a708b084d7e05a118",
+        "type": "github"
+      },
+      "original": {
+        "owner": "jkachmar",
+        "repo": "easy-hls-nix",
+        "type": "github"
+      }
+    },
+    "flake-utils": {
+      "locked": {
+        "lastModified": 1634851050,
+        "narHash": "sha256-N83GlSGPJJdcqhUxSCS/WwW5pksYf3VP1M13cDRTSVA=",
+        "owner": "numtide",
+        "repo": "flake-utils",
+        "rev": "c91f3de5adaf1de973b797ef7485e441a65b8935",
+        "type": "github"
+      },
+      "original": {
+        "owner": "numtide",
+        "repo": "flake-utils",
+        "type": "github"
+      }
+    },
+    "nixpkgs": {
+      "locked": {
+        "lastModified": 1636983198,
+        "narHash": "sha256-ductPDqewBTMB0ZWSJo3wc99RaR6MzbRf6wjWsMjqoM=",
+        "owner": "nixos",
+        "repo": "nixpkgs",
+        "rev": "d04b41c582c69405f1fb1272711967f777cca883",
+        "type": "github"
+      },
+      "original": {
+        "owner": "nixos",
+        "repo": "nixpkgs",
+        "type": "github"
+      }
+    },
+    "nixpkgs_2": {
+      "locked": {
+        "lastModified": 1636979576,
+        "narHash": "sha256-Iy2J3T7xyHk43cVj4gGv74MKvVOCOqoqzffO3k5mbpU=",
+        "owner": "NixOS",
+        "repo": "nixpkgs",
+        "rev": "4ea0167baf7126e424edb7ed2be27c0f6008dafb",
+        "type": "github"
+      },
+      "original": {
+        "id": "nixpkgs",
+        "type": "indirect"
+      }
+    },
+    "root": {
+      "inputs": {
+        "easy-hls-src": "easy-hls-src",
+        "flake-utils": "flake-utils",
+        "nixpkgs": "nixpkgs_2"
+      }
+    }
+  },
+  "root": "root",
+  "version": 7
+}
diff --git a/flake.nix b/flake.nix
new file mode 100644
index 0000000..559ad3f
--- /dev/null
+++ b/flake.nix
@@ -0,0 +1,46 @@
+{
+  description = "FeedMonad";
+
+  inputs = {
+    easy-hls-src = { url = "github:jkachmar/easy-hls-nix"; };
+    flake-utils = { url = "github:numtide/flake-utils"; };
+  };
+
+  outputs = { self, nixpkgs, flake-utils, easy-hls-src }:
+    flake-utils.lib.eachSystem ["x86_64-linux" "x86_64-darwin"] ( system:
+      let
+        pkgs = nixpkgs.legacyPackages.${system};
+        hp = pkgs.haskellPackages.extend (self: super: {
+            FeedMonad = self.callPackage ./FeedMonad {};
+            FeedMonad-demo = self.callPackage ./FeedMonad-demo {};
+          });
+        easy-hls = pkgs.callPackage easy-hls-src { ghcVersions = [ hp.ghc.version ]; };
+      in
+      rec {
+
+        packages = { inherit (hp) FeedMonad FeedMonad-demo; };
+
+        defaultPackage = packages.FeedMonad;
+        apps.FeedMonad-demo = {
+          type = "app";
+          program = "${hp.FeedMonad-demo}/bin/FeedMonad-demo";
+        };
+        devShell = hp.shellFor {
+          packages = h: [h.FeedMonad h.FeedMonad-demo];
+          withHoogle = true;
+          buildInputs = with pkgs; [
+            entr
+            cabal-install
+            hp.hlint
+            stylish-haskell
+            ghcid
+            easy-hls
+
+            sqlite-interactive
+
+            hp.graphmod
+          ];
+        };
+      }
+    );
+}
diff --git a/shell.nix b/shell.nix
index c0ff229..c44a522 100644
--- a/shell.nix
+++ b/shell.nix
@@ -1,35 +1,8 @@
-{ nixpkgs ? import <nixpkgs> {} }:
-
-with nixpkgs;
-
-let
-  easy-hls-src = fetchFromGitHub {
-    owner = "ssbothwell";
-    repo = "easy-hls-nix";
-    inherit (builtins.fromJSON (builtins.readFile ./easy-hls-nix.json)) rev sha256;
-  };
-  easy-hls = callPackage easy-hls-src { ghcVersions = [ hp.ghc.version ]; };
-  hp = haskellPackages.extend (self: super: {
-    FeedMonad = self.callPackage ./FeedMonad {};
-    FeedMonad-demo = self.callPackage ./FeedMonad-demo {};
-  });
-
-in
-
-hp.shellFor {
-  packages = h: [h.FeedMonad h.FeedMonad-demo];
-  withHoogle = true;
-  buildInputs = [
-    entr
-    cabal-install
-    haskellPackages.hlint
-    stylish-haskell
-    ghcid
-    easy-hls
-
-    sqlite-interactive
-
-    haskellPackages.graphmod
-  ];
-}
-
+# https://nixos.wiki/wiki/Flakes#Using_flakes_project_from_a_legacy_Nix
+(import (
+  fetchTarball {
+    url = "https://github.com/edolstra/flake-compat/archive/99f1c2157fba4bfe6211a321fd0ee43199025dbf.tar.gz";
+    sha256 = "0x2jn3vrawwv9xp15674wjz9pixwjyj3j771izayl962zziivbx2"; }
+) {
+  src =  ./.;
+}).defaultNix