diff --git a/.envrc b/.envrc
new file mode 100644
index 0000000..be81fed
--- /dev/null
+++ b/.envrc
@@ -0,0 +1 @@
+eval "$(lorri direnv)"
\ No newline at end of file
diff --git a/Cargo.lock b/Cargo.lock
index 0ea51f1..c740678 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -25,7 +25,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 
 [[package]]
 name = "bootloader"
-version = "0.8.8"
+version = "0.8.9"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
 [[package]]
@@ -78,7 +78,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 
 [[package]]
 name = "linked_list_allocator"
-version = "0.7.0"
+version = "0.8.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "spinning_top 0.1.0 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -113,7 +113,7 @@ dependencies = [
 
 [[package]]
 name = "num-rational"
-version = "0.2.3"
+version = "0.2.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "autocfg 1.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -192,7 +192,7 @@ version = "0.2.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "bitflags 1.2.1 (registry+https://github.com/rust-lang/crates.io-index)",
- "x86_64 0.9.5 (registry+https://github.com/rust-lang/crates.io-index)",
+ "x86_64 0.9.6 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
@@ -212,7 +212,7 @@ source = "git+https://tulpa.dev/xeos/wasmi#0b6dd64219cc73e8fc58cfdfdd89a314b1d41
 dependencies = [
  "libm 0.1.4 (registry+https://github.com/rust-lang/crates.io-index)",
  "memory_units 0.3.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "num-rational 0.2.3 (registry+https://github.com/rust-lang/crates.io-index)",
+ "num-rational 0.2.4 (registry+https://github.com/rust-lang/crates.io-index)",
  "num-traits 0.2.11 (registry+https://github.com/rust-lang/crates.io-index)",
  "parity-wasm 0.40.3 (registry+https://github.com/rust-lang/crates.io-index)",
  "wasmi-validation 0.2.0 (git+https://tulpa.dev/xeos/wasmi)",
@@ -240,7 +240,7 @@ dependencies = [
 
 [[package]]
 name = "x86_64"
-version = "0.9.5"
+version = "0.9.6"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "bit_field 0.9.0 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -251,12 +251,12 @@ dependencies = [
 name = "xe_os"
 version = "0.1.0"
 dependencies = [
- "bootloader 0.8.8 (registry+https://github.com/rust-lang/crates.io-index)",
+ "bootloader 0.8.9 (registry+https://github.com/rust-lang/crates.io-index)",
  "chrono 0.4.9 (git+https://tulpa.dev/xeos/chrono)",
  "cmos 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "compiler_builtins 0.1.26 (git+https://github.com/rust-lang/compiler-builtins)",
  "lazy_static 1.4.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "linked_list_allocator 0.7.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "linked_list_allocator 0.8.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "pc-keyboard 0.3.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "pic8259_simple 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "spin 0.5.2 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -271,7 +271,7 @@ dependencies = [
 "checksum autocfg 1.0.0 (registry+https://github.com/rust-lang/crates.io-index)" = "f8aac770f1885fd7e387acedd76065302551364496e46b3dd00860b2f8359b9d"
 "checksum bit_field 0.9.0 (registry+https://github.com/rust-lang/crates.io-index)" = "ed8765909f9009617974ab6b7d332625b320b33c326b1e9321382ef1999b5d56"
 "checksum bitflags 1.2.1 (registry+https://github.com/rust-lang/crates.io-index)" = "cf1de2fe8c75bc145a2f577add951f8134889b4795d47466a54a5c846d691693"
-"checksum bootloader 0.8.8 (registry+https://github.com/rust-lang/crates.io-index)" = "c3ed4f735c4e455ba86a3d2939b1c0729414153642106c9d035693355630a42c"
+"checksum bootloader 0.8.9 (registry+https://github.com/rust-lang/crates.io-index)" = "152a28c753e229e037e910b4cd4cd16a90c53dd9a67fd751fa304b4b4a03970c"
 "checksum cast 0.2.3 (registry+https://github.com/rust-lang/crates.io-index)" = "4b9434b9a5aa1450faa3f9cb14ea0e8c53bb5d2b3c1bfd1ab4fc03e9f33fbfb0"
 "checksum chrono 0.4.9 (git+https://tulpa.dev/xeos/chrono)" = "<none>"
 "checksum cmos 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)" = "0a5377a95644e12ea6460d19d59692c40a5fc65d0eb2ad34390c12cbb5a64095"
@@ -279,12 +279,12 @@ dependencies = [
 "checksum cpuio 0.2.0 (registry+https://github.com/rust-lang/crates.io-index)" = "22b8e308ccfc5acf3b82f79c0eac444cf6114cb2ac67a230ca6c177210068daa"
 "checksum lazy_static 1.4.0 (registry+https://github.com/rust-lang/crates.io-index)" = "e2abad23fbc42b3700f2f279844dc832adb2b2eb069b2df918f455c4e18cc646"
 "checksum libm 0.1.4 (registry+https://github.com/rust-lang/crates.io-index)" = "7fc7aa29613bd6a620df431842069224d8bc9011086b1db4c0e0cd47fa03ec9a"
-"checksum linked_list_allocator 0.7.0 (registry+https://github.com/rust-lang/crates.io-index)" = "411991593f041990abf72f6715903fe67770e710e3c95a6d2e98a7550270136a"
+"checksum linked_list_allocator 0.8.1 (registry+https://github.com/rust-lang/crates.io-index)" = "5825aea823c659d0fdcdbe8c9b78baf56f3a10365d783db874f6d360df72626f"
 "checksum lock_api 0.3.3 (registry+https://github.com/rust-lang/crates.io-index)" = "79b2de95ecb4691949fea4716ca53cdbcfccb2c612e19644a8bad05edcf9f47b"
 "checksum memory_units 0.3.0 (registry+https://github.com/rust-lang/crates.io-index)" = "71d96e3f3c0b6325d8ccd83c33b28acb183edcb6c67938ba104ec546854b0882"
 "checksum nodrop 0.1.14 (registry+https://github.com/rust-lang/crates.io-index)" = "72ef4a56884ca558e5ddb05a1d1e7e1bfd9a68d9ed024c21704cc98872dae1bb"
 "checksum num-integer 0.1.42 (registry+https://github.com/rust-lang/crates.io-index)" = "3f6ea62e9d81a77cd3ee9a2a5b9b609447857f3d358704331e4ef39eb247fcba"
-"checksum num-rational 0.2.3 (registry+https://github.com/rust-lang/crates.io-index)" = "da4dc79f9e6c81bef96148c8f6b8e72ad4541caa4a24373e900a36da07de03a3"
+"checksum num-rational 0.2.4 (registry+https://github.com/rust-lang/crates.io-index)" = "5c000134b5dbf44adc5cb772486d335293351644b801551abe8f75c84cfa4aef"
 "checksum num-traits 0.2.11 (registry+https://github.com/rust-lang/crates.io-index)" = "c62be47e61d1842b9170f0fdeec8eba98e60e90e5446449a0545e5152acd7096"
 "checksum parity-wasm 0.40.3 (registry+https://github.com/rust-lang/crates.io-index)" = "1e39faaa292a687ea15120b1ac31899b13586446521df6c149e46f1584671e0f"
 "checksum pc-keyboard 0.3.1 (registry+https://github.com/rust-lang/crates.io-index)" = "fff50ab09ba31bcebc0669f4e64c0952fae1acdca9e6e0587e68e4e8443808ac"
@@ -301,4 +301,4 @@ dependencies = [
 "checksum wasmi 0.5.1 (git+https://tulpa.dev/xeos/wasmi)" = "<none>"
 "checksum wasmi-validation 0.2.0 (git+https://tulpa.dev/xeos/wasmi)" = "<none>"
 "checksum x86_64 0.7.7 (registry+https://github.com/rust-lang/crates.io-index)" = "1f27d9168654aee1b0c1b73746caeb4aa33248f8b8c8f6e100e697fcc2a794b2"
-"checksum x86_64 0.9.5 (registry+https://github.com/rust-lang/crates.io-index)" = "4e6a3f047ad0844d3b4794f34d1095aefb918241064663d4163db8c7d4a76edf"
+"checksum x86_64 0.9.6 (registry+https://github.com/rust-lang/crates.io-index)" = "4206b60c9f99766329b66962aa8ddc01df6c7edd02edc046b7a69d5df9fcdbcf"
diff --git a/Cargo.toml b/Cargo.toml
index 113185a..9cd711c 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -14,7 +14,7 @@ x86_64 = "0.7.5"
 uart_16550 = "0.2.0"
 pic8259_simple = "0.1.1"
 pc-keyboard = "0.3.1"
-linked_list_allocator = "0.7"
+linked_list_allocator = "0"
 wasmi = {git = "https://tulpa.dev/xeos/wasmi", default-features=false, features = ["core"] }
 compiler_builtins = { git = "https://github.com/rust-lang/compiler-builtins" }
 chrono = { git = "https://tulpa.dev/xeos/chrono", default-features=false, features = ["alloc"] }
diff --git a/nix/bootimage.nix b/nix/bootimage.nix
new file mode 100644
index 0000000..2c4422d
--- /dev/null
+++ b/nix/bootimage.nix
@@ -0,0 +1,21 @@
+{ sources ? import ./sources.nix, rust ? import ./rust.nix { }
+, pkgs ? import sources.nixpkgs { } }:
+
+with pkgs;
+
+rustPlatform.buildRustPackage rec {
+  pname = "bootimage";
+  version = "0.7.8";
+
+  inherit rust;
+
+  src = fetchFromGitHub {
+    owner = "rust-osdev";
+    repo = pname;
+    rev = "v${version}";
+    sha256 = "1rczflf6fllxkag5nah195shwqvqmlna9a1gkcwp9ljlgxlr9zvq";
+  };
+
+  cargoSha256 = "17ssdz0m5kk1arh34gi8xrcaskd8ibx43m0gq6vkyh3bc7ybxmgf";
+}
+
diff --git a/nix/rust.nix b/nix/rust.nix
new file mode 100644
index 0000000..006ee8a
--- /dev/null
+++ b/nix/rust.nix
@@ -0,0 +1,9 @@
+{ sources ? import ./sources.nix }:
+
+let
+  pkgs =
+    import sources.nixpkgs { overlays = [ (import sources.nixpkgs-mozilla) ]; };
+in (pkgs.rustChannelOf {
+  date = "2020-03-25";
+  channel = "nightly";
+}).rust.override { extensions = [ "rust-src" ]; }
diff --git a/nix/sources.json b/nix/sources.json
new file mode 100644
index 0000000..d891c1b
--- /dev/null
+++ b/nix/sources.json
@@ -0,0 +1,38 @@
+{
+    "niv": {
+        "branch": "master",
+        "description": "Easy dependency management for Nix projects",
+        "homepage": "https://github.com/nmattia/niv",
+        "owner": "nmattia",
+        "repo": "niv",
+        "rev": "98c74a80934123cb4c3bf3314567f67311eb711a",
+        "sha256": "1w8n54hapd4x9f1am33icvngkqns7m3hl9yair38yqq08ffwg0kn",
+        "type": "tarball",
+        "url": "https://github.com/nmattia/niv/archive/98c74a80934123cb4c3bf3314567f67311eb711a.tar.gz",
+        "url_template": "https://github.com/<owner>/<repo>/archive/<rev>.tar.gz"
+    },
+    "nixpkgs": {
+        "branch": "nixos-19.09",
+        "description": "A read-only mirror of NixOS/nixpkgs tracking the released channels. Send issues and PRs to",
+        "homepage": "https://github.com/NixOS/nixpkgs",
+        "owner": "NixOS",
+        "repo": "nixpkgs-channels",
+        "rev": "bf7c0f0461e047bec108a5c5d5d1b144289a65ba",
+        "sha256": "01dsh9932x6xcba2p0xg4n563b85i3p7s2sakj7yf2ws8pgmwhq9",
+        "type": "tarball",
+        "url": "https://github.com/NixOS/nixpkgs-channels/archive/bf7c0f0461e047bec108a5c5d5d1b144289a65ba.tar.gz",
+        "url_template": "https://github.com/<owner>/<repo>/archive/<rev>.tar.gz"
+    },
+    "nixpkgs-mozilla": {
+        "branch": "master",
+        "description": "mozilla related nixpkgs (extends nixos/nixpkgs repo)",
+        "homepage": null,
+        "owner": "mozilla",
+        "repo": "nixpkgs-mozilla",
+        "rev": "e912ed483e980dfb4666ae0ed17845c4220e5e7c",
+        "sha256": "08fvzb8w80bkkabc1iyhzd15f4sm7ra10jn32kfch5klgl0gj3j3",
+        "type": "tarball",
+        "url": "https://github.com/mozilla/nixpkgs-mozilla/archive/e912ed483e980dfb4666ae0ed17845c4220e5e7c.tar.gz",
+        "url_template": "https://github.com/<owner>/<repo>/archive/<rev>.tar.gz"
+    }
+}
diff --git a/nix/sources.nix b/nix/sources.nix
new file mode 100644
index 0000000..f69e4d9
--- /dev/null
+++ b/nix/sources.nix
@@ -0,0 +1,133 @@
+# This file has been generated by Niv.
+
+let
+
+  #
+  # The fetchers. fetch_<type> fetches specs of type <type>.
+  #
+
+  fetch_file = pkgs: spec:
+    if spec.builtin or true then
+      builtins_fetchurl { inherit (spec) url sha256; }
+    else
+      pkgs.fetchurl { inherit (spec) url sha256; };
+
+  fetch_tarball = pkgs: spec:
+    if spec.builtin or true then
+      builtins_fetchTarball { inherit (spec) url sha256; }
+    else
+      pkgs.fetchzip { inherit (spec) url sha256; };
+
+  fetch_git = spec:
+    builtins.fetchGit {
+      url = spec.repo;
+      inherit (spec) rev ref;
+    };
+
+  fetch_builtin-tarball = spec:
+    builtins.trace ''
+      WARNING:
+        The niv type "builtin-tarball" will soon be deprecated. You should
+        instead use `builtin = true`.
+
+        $ niv modify <package> -a type=tarball -a builtin=true
+    '' builtins_fetchTarball { inherit (spec) url sha256; };
+
+  fetch_builtin-url = spec:
+    builtins.trace ''
+      WARNING:
+        The niv type "builtin-url" will soon be deprecated. You should
+        instead use `builtin = true`.
+
+        $ niv modify <package> -a type=file -a builtin=true
+    '' (builtins_fetchurl { inherit (spec) url sha256; });
+
+  #
+  # Various helpers
+  #
+
+  # The set of packages used when specs are fetched using non-builtins.
+  mkPkgs = sources:
+    let
+      sourcesNixpkgs =
+        import (builtins_fetchTarball { inherit (sources.nixpkgs) url sha256; })
+        { };
+      hasNixpkgsPath = builtins.any (x: x.prefix == "nixpkgs") builtins.nixPath;
+      hasThisAsNixpkgsPath = <nixpkgs> == ./.;
+    in if builtins.hasAttr "nixpkgs" sources then
+      sourcesNixpkgs
+    else if hasNixpkgsPath && !hasThisAsNixpkgsPath then
+      import <nixpkgs> { }
+    else
+      abort ''
+        Please specify either <nixpkgs> (through -I or NIX_PATH=nixpkgs=...) or
+        add a package called "nixpkgs" to your sources.json.
+      '';
+
+  # The actual fetching function.
+  fetch = pkgs: name: spec:
+
+    if !builtins.hasAttr "type" spec then
+      abort "ERROR: niv spec ${name} does not have a 'type' attribute"
+    else if spec.type == "file" then
+      fetch_file pkgs spec
+    else if spec.type == "tarball" then
+      fetch_tarball pkgs spec
+    else if spec.type == "git" then
+      fetch_git spec
+    else if spec.type == "builtin-tarball" then
+      fetch_builtin-tarball spec
+    else if spec.type == "builtin-url" then
+      fetch_builtin-url spec
+    else
+      abort
+      "ERROR: niv spec ${name} has unknown type ${builtins.toJSON spec.type}";
+
+  # Ports of functions for older nix versions
+
+  # a Nix version of mapAttrs if the built-in doesn't exist
+  mapAttrs = builtins.mapAttrs or (f: set:
+    with builtins;
+    listToAttrs (map (attr: {
+      name = attr;
+      value = f attr set.${attr};
+    }) (attrNames set)));
+
+  # fetchTarball version that is compatible between all the versions of Nix
+  builtins_fetchTarball = { url, sha256 }@attrs:
+    let inherit (builtins) lessThan nixVersion fetchTarball;
+    in if lessThan nixVersion "1.12" then
+      fetchTarball { inherit url; }
+    else
+      fetchTarball attrs;
+
+  # fetchurl version that is compatible between all the versions of Nix
+  builtins_fetchurl = { url, sha256 }@attrs:
+    let inherit (builtins) lessThan nixVersion fetchurl;
+    in if lessThan nixVersion "1.12" then
+      fetchurl { inherit url; }
+    else
+      fetchurl attrs;
+
+  # Create the final "sources" from the config
+  mkSources = config:
+    mapAttrs (name: spec:
+      if builtins.hasAttr "outPath" spec then
+        abort
+        "The values in sources.json should not have an 'outPath' attribute"
+      else
+        spec // { outPath = fetch config.pkgs name spec; }) config.sources;
+
+  # The "config" used by the fetchers
+  mkConfig = { sourcesFile ? ./sources.json
+    , sources ? builtins.fromJSON (builtins.readFile sourcesFile)
+    , pkgs ? mkPkgs sources }: rec {
+      # The sources, i.e. the attribute set of spec name to spec
+      inherit sources;
+
+      # The "pkgs" (evaluated nixpkgs) to use for e.g. non-builtin fetchers
+      inherit pkgs;
+    };
+in mkSources (mkConfig { }) // {
+  __functor = _: settings: mkSources (mkConfig settings);
+}
diff --git a/shell.nix b/shell.nix
new file mode 100644
index 0000000..92e0b09
--- /dev/null
+++ b/shell.nix
@@ -0,0 +1,8 @@
+let
+  pkgs = import <nixpkgs> { };
+  sources = import ./nix/sources.nix;
+  rust = import ./nix/rust.nix { inherit sources; };
+  bootimage = import ./nix/bootimage.nix { inherit sources pkgs; };
+in pkgs.mkShell {
+  buildInputs = with pkgs; [ rust cargo-xbuild qemu bootimage ];
+}