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 "cells": [
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "# Creating a Docker image\n",
    "\n",
    "In this tutorial we will create Docker images using Nix and the `dockerTools` functions in Nixpkgs."
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "## Create a simple image\n",
    "\n",
    "In the following example we create a Docker image that contains only Python."
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "%%file default.nix\n",
    "\n",
    "with import (fetchTarball \"channel:nixos-20.03\") {};\n",
    "\n",
    "dockerTools.buildImage {\n",
    "  name = \"python\";\n",
    "  config = {\n",
    "    Cmd = [\n",
    "      \"${python3}/bin/python3 -c 'print(\\\"hello\\\")'\"\n",
    "    ];\n",
    "  };\n",
    "}"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "Let's build the image."
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "! nix-build"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "Now we have our Docker image in the store. Note how small it is"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "! du -h $(nix-build)"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "To run the image as a container, just load it with `docker load`\n",
    "```sh\n",
    "docker load < $(nix-build)\n",
    "```\n",
    "It's not shown here because the Docker daemon is not available."
   ]
  }
 ],
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