Also expose a nixpkgs overlay (#3)

README.md

@@ -7,7 +7,19 @@ Interactively browse the dependency graph of your Nix derivations.
 ## Installation
 
 ```
-nix-env -iA exe -f https://github.com/utdemir/nixdu/archive/master.tar.gz
+nix-env -iA nixdu -f https://github.com/utdemir/nixdu/archive/master.tar.gz
+```
+
+A nixpkgs overlay is also provided via `overlay.nix`, that can be used
+with tools like [home-manager][]:
+
+```nix
+nixpkgs.overlays = [
+  (let url = https://github.com/utdemir/nixdu/archive/master.tar.gz;
+    in import "${builtins.fetchTarball url}/overlay.nix" {})
+];
+
+home.packages = [ pkgs.nixdu ];
 ```
 
 ## Usage
@@ -24,3 +36,5 @@ Keybindings:
   i               : Toggle modeline
   ?               : Show help
 ```
+
+[home-manager]: https://github.com/rycee/home-manager

default.nix

@@ -1,46 +1,25 @@
 let
   sources = import ./nix/sources.nix;
-  pkgs = import sources.nixpkgs { };
-
-  gitignore = extra:
-    pkgs.nix-gitignore.gitignoreSourcePure ([ ./.gitignore ] ++ extra);
-
-  myHaskellPackages = pkgs.haskellPackages.override {
-    overrides = hself: hsuper: {
-      "nixdu" =
-        hself.callCabal2nix
-          "nixdu"
-          (gitignore [ "asciicast.sh" ] ./.) { };
-    };
+  pkgs = import sources.nixpkgs {
+    overlays = [ (import ./overlay.nix) ];
   };
 
-  shell = myHaskellPackages.shellFor {
+  shell = pkgs.haskellPackages.shellFor {
     packages = p: [
       p."nixdu"
     ];
     buildInputs = with pkgs.haskellPackages; [
-      myHaskellPackages.cabal-install
+      cabal-install
       ghcid
       ormolu
       hlint
       steeloverseer
-      (import sources.niv { }).niv
       pkgs.nixpkgs-fmt
     ];
     withHoogle = true;
   };
-
-  exe = pkgs.haskell.lib.justStaticExecutables (myHaskellPackages."nixdu");
-
-  docker = pkgs.dockerTools.buildImage {
-    name = "nixdu";
-    config.Cmd = [ "${exe}/bin/nixdu" ];
-  };
 in
 {
   inherit shell;
-  inherit exe;
-  inherit docker;
-  inherit myHaskellPackages;
-  "nixdu" = myHaskellPackages."nixdu";
+  inherit (pkgs) nixdu;
 }

nix/sources.json

@@ -1,16 +1,4 @@
 {
-    "niv": {
-        "branch": "master",
-        "description": "Easy dependency management for Nix projects",
-        "homepage": "https://github.com/nmattia/niv",
-        "owner": "nmattia",
-        "repo": "niv",
-        "rev": "f73bf8d584148677b01859677a63191c31911eae",
-        "sha256": "0jlmrx633jvqrqlyhlzpvdrnim128gc81q5psz2lpp2af8p8q9qs",
-        "type": "tarball",
-        "url": "https://github.com/nmattia/niv/archive/f73bf8d584148677b01859677a63191c31911eae.tar.gz",
-        "url_template": "https://github.com/<owner>/<repo>/archive/<rev>.tar.gz"
-    },
     "nixpkgs": {
         "branch": "nixpkgs-unstable",
         "description": "Nix Packages collection",

overlay.nix

@@ -0,0 +1,18 @@
+self: super: {
+  haskellPackages =
+    super.haskellPackages.override {
+      overrides = hself: hsuper: {
+        nixdu =
+          hself.callCabal2nix
+            "nixdu"
+            (self.nix-gitignore.gitignoreSourcePure
+              [ ./.gitignore "asciicast.sh" "*.nix" ]
+              ./.
+            ) { };
+      };
+    };
+
+  nixdu =
+    self.haskell.lib.justStaticExecutables
+      self.haskellPackages.nixdu;
+}