README.md: repo example

README.md

@@ -36,7 +36,7 @@ For NixOS add the following to your `/etc/nixos/configuration.nix`:
     nur = pkgs.callPackage (import (builtins.fetchGit {
       url = "https://github.com/nix-community/NUR";
     })) {};
-  }
+  };
 }
 ```
 
@@ -79,23 +79,76 @@ DO NOT import packages for example `with import <nixpkgs> {};`.
 Instead take all dependency you want to import from nixpkgs by function arguments.
 Each repository should return a set of nix derivations:
 
-```
+```nix
 { callPackage }:
 {
   inxi = callPackage ./inxi {};
 }
 ```
 
-In this example `inxi` would be a directory
+In this example `inxi` would be a directory containing a `default.nix`:
+
+```nix
+{ stdenv, fetchFromGitHub
+, makeWrapper, perl
+, dmidecode, file, hddtemp, nettools, iproute, lm_sensors, usbutils, kmod, xlibs
+}:
+
+let
+  path = [
+    dmidecode file hddtemp nettools iproute lm_sensors usbutils kmod
+    xlibs.xdpyinfo xlibs.xprop xlibs.xrandr
+  ];
+in stdenv.mkDerivation rec {
+  name = "inxi-${version}";
+  version = "3.0.14-1";
+
+  src = fetchFromGitHub {
+    owner = "smxi";
+    repo = "inxi";
+    rev = version;
+    sha256 = "0wyv8cqwy7jlv2r3j7w8ri73iywawnaihww39vlpnpjjcz1b37hw";
+  };
+
+  installPhase = ''
+    install -D -m755 inxi $out/bin/inxi
+    install -D inxi.1 $out/man/man1/inxi.1
+    wrapProgram $out/bin/inxi \
+      --prefix PATH : ${ stdenv.lib.makeBinPath path }
+  '';
+
+  buildInputs = [ perl ];
+  nativeBuildInputs = [ makeWrapper ];
+
+  meta = with stdenv.lib; {
+    description = "System information tool";
+    homepage = https://github.com/smxi/inxi;
+    license = licenses.gpl3;
+    platforms = platforms.linux;
+  };
+}
+```
+
+You can use `nix-shell` or `nix-build` to build your packages:
+
+```console
+$ nix-shell -E 'with import <nixpkgs>{}; (callPackage ./default.nix {}).inxi'
+nix-shell> inxi
+nix-shell> find $buildInputs
+```
+
+```console
+$ nix-build -E 'with import <nixpkgs>{}; (callPackage ./default.nix {})'
+```
 
 Add your own repository to in the `repos.json` of NUR:
 
-```
+```console
 $ git clone https://github.com/nix-community/NUR
 # open and modify repos.json in an editor
 ```
 
-```
+```json
 {
     "repos": {
         "mic92": {