diff --git a/enter-nix-shell b/enter-nix-shell
deleted file mode 100755
index c6ce419..0000000
--- a/enter-nix-shell
+++ /dev/null
@@ -1,12 +0,0 @@
-#!/bin/sh
-
-# This script uses nix-shell to build an environment suitable for developing and testing this package
-
-# Run this with the "start" argument to automatically download deps and
-# start talking to asjon in the CLI :)
-
-if [ "$1" == "start" ]; then
-  nix-shell -p gnumake python2 nodejs --command "npm install && bin/hubot"
-else
-  nix-shell -p gnumake python2 nodejs
-fi
diff --git a/shell.nix b/shell.nix
new file mode 100644
index 0000000..f218e83
--- /dev/null
+++ b/shell.nix
@@ -0,0 +1,47 @@
+{ pkgs ? import <nixpkgs> {}, mode ? "shell" }:
+
+with pkgs.lib;
+
+let
+
+modes = {
+  shell = "exec zsh";
+  test  = "npm test";
+  run   = "exec bin/hubot";
+  runTg = ''
+    telegram-cli \
+      -dWE                \
+      -Z $HUBOT_TG_SCRIPT \
+      -P $HUBOT_TG_PORT   > /dev/null 2>&1 &
+    bin/hubot -a tg
+    pkill -9 telegram-wo-key; exit
+  '';
+};
+
+telegram = pkgs.telegram-cli.override {
+  python = pkgs.python3;
+};
+
+in pkgs.stdenv.mkDerivation rec {
+  name = "asjon-dev";
+  source = ".";
+
+  buildInputs = node ++ external;
+  node = with pkgs.nodePackages; [
+    pkgs.nodejs
+    mocha
+    coffee-script
+  ];
+  external = with pkgs; [
+    zsh
+    telegram
+    graphicsmagick
+  ];
+
+  shellHook = environment + getAttr mode modes;
+  environment = ''
+    #set env variables here
+    export HUBOT_TG_SCRIPT=node_modules/hubot-tg/hubot.py
+    export HUBOT_TG_PORT=1123
+  '';
+}