diff --git a/.envrc b/.envrc
index 051d09d..cded9d7 100644
--- a/.envrc
+++ b/.envrc
@@ -1 +1,4 @@
-eval "$(lorri direnv)"
+use nix
+
+export MIX_HOME=$(pwd)/.mix
+export PATH=$PATH:$(pwd)/.mix/escripts
diff --git a/.gitignore b/.gitignore
index 9d71119..f6278de 100644
--- a/.gitignore
+++ b/.gitignore
@@ -7,3 +7,4 @@ erl_crash.dump
 *.beam
 .DS_Store
 mix.lock
+.mix
diff --git a/nix/commands.nix b/nix/commands.nix
deleted file mode 100644
index 5499478..0000000
--- a/nix/commands.nix
+++ /dev/null
@@ -1,87 +0,0 @@
-{ pkgs, unstable, ... }:
-  let
-    bash    = "${pkgs.bash}/bin/bash";
-    figlet  = "${pkgs.figlet}/bin/figlet";
-    lolcat  = "${pkgs.lolcat}/bin/lolcat";
-    mix     = "${unstable.elixir}/bin/mix";
-
-    cmd = description: script:
-      { inherit description;
-        inherit script;
-      };
-
-    command = {name, script, description ? "<No description given>"}:
-      let
-        package =
-          pkgs.writeScriptBin name ''
-            #!${bash}
-            echo "⚙️  Running ${name}..."
-            ${script}
-          '';
-
-        bin = "${package}/bin/${name}";
-      in
-         { package     = package;
-           description = description;
-           bin         = bin;
-         };
-
-    commands = defs:
-      let
-        names =
-          builtins.attrNames defs;
-
-        helper =
-          let
-            lengths = map builtins.stringLength names;
-            maxLen  = builtins.foldl' (acc: x: if x > acc then x else acc) 0 lengths;
-            maxPad  =
-              let
-                go = acc:
-                  if builtins.stringLength acc >= maxLen
-                  then acc
-                  else go (" " + acc);
-              in
-                go "";
-
-            folder = acc: name:
-              let
-                nameLen = builtins.stringLength name;
-                padLen  = maxLen - nameLen;
-                padding = builtins.substring 0 padLen maxPad;
-              in
-                acc + " && echo '${name} ${padding}| ${(builtins.getAttr name defs).description}'";
-
-            lines =
-              builtins.foldl' folder "echo ''" names;
-
-          in
-            pkgs.writeScriptBin "helpme" ''
-              #!${pkgs.stdenv.shell}
-              ${pkgs.figlet}/bin/figlet "Commands" | ${pkgs.lolcat}/bin/lolcat
-              ${toString lines}
-            '';
-
-        mapper = name:
-          let
-            element =
-              builtins.getAttr name defs;
-
-            task = command {
-              inherit name;
-              description = element.description;
-              script      = element.script;
-            };
-          in
-            task.package;
-
-        packages =
-          map mapper names;
-
-      in
-        [helper] ++ packages;
-
-  in
-    commands {
-      quality = cmd "Run all tests, linters, and so on" "MIX_ENV=test ${mix} quality";
-    }
diff --git a/nix/sources.json b/nix/sources.json
deleted file mode 100644
index 189720c..0000000
--- a/nix/sources.json
+++ /dev/null
@@ -1,50 +0,0 @@
-{
-    "darwin": {
-        "branch": "nixpkgs-20.09-darwin",
-        "description": "Nix Packages collection",
-        "homepage": "",
-        "owner": "NixOS",
-        "repo": "nixpkgs",
-        "rev": "e716ddfac4be879ffbae75c3914a538dd5d4d12e",
-        "sha256": "0c2090sz4nvd1bqa9bfz3b6mj0q8b7v4jzgsykn2hf291l3h94d6",
-        "type": "tarball",
-        "url": "https://github.com/NixOS/nixpkgs/archive/e716ddfac4be879ffbae75c3914a538dd5d4d12e.tar.gz",
-        "url_template": "https://github.com/<owner>/<repo>/archive/<rev>.tar.gz"
-    },
-    "niv": {
-        "branch": "master",
-        "description": "Easy dependency management for Nix projects",
-        "homepage": "https://github.com/nmattia/niv",
-        "owner": "nmattia",
-        "repo": "niv",
-        "rev": "af958e8057f345ee1aca714c1247ef3ba1c15f5e",
-        "sha256": "1qjavxabbrsh73yck5dcq8jggvh3r2jkbr6b5nlz5d9yrqm9255n",
-        "type": "tarball",
-        "url": "https://github.com/nmattia/niv/archive/af958e8057f345ee1aca714c1247ef3ba1c15f5e.tar.gz",
-        "url_template": "https://github.com/<owner>/<repo>/archive/<rev>.tar.gz"
-    },
-    "nixpkgs": {
-        "branch": "nixos-20.09",
-        "description": "Nix Packages collection",
-        "homepage": "",
-        "owner": "NixOS",
-        "repo": "nixpkgs",
-        "rev": "60b18a066e8ce5dd21ebff5324345d3586a67ad9",
-        "sha256": "1cr7r16vb4nxifykhak8awspdpr775kafrl7p6asgwicsng7giya",
-        "type": "tarball",
-        "url": "https://github.com/NixOS/nixpkgs/archive/60b18a066e8ce5dd21ebff5324345d3586a67ad9.tar.gz",
-        "url_template": "https://github.com/<owner>/<repo>/archive/<rev>.tar.gz"
-    },
-    "unstable": {
-        "branch": "nixpkgs-unstable",
-        "description": "Nix Packages collection",
-        "homepage": null,
-        "owner": "NixOS",
-        "repo": "nixpkgs",
-        "rev": "c5147860e23ed75ce9d40298c66b416c00be1167",
-        "sha256": "104mw4rfbzyrfkxq468dlk38drrjx92dgyvkazgci67a6cx3n6nx",
-        "type": "tarball",
-        "url": "https://github.com/NixOS/nixpkgs/archive/c5147860e23ed75ce9d40298c66b416c00be1167.tar.gz",
-        "url_template": "https://github.com/<owner>/<repo>/archive/<rev>.tar.gz"
-    }
-}
diff --git a/nix/sources.nix b/nix/sources.nix
deleted file mode 100644
index 1938409..0000000
--- a/nix/sources.nix
+++ /dev/null
@@ -1,174 +0,0 @@
-# This file has been generated by Niv.
-
-let
-
-  #
-  # The fetchers. fetch_<type> fetches specs of type <type>.
-  #
-
-  fetch_file = pkgs: name: spec:
-    let
-      name' = sanitizeName name + "-src";
-    in
-      if spec.builtin or true then
-        builtins_fetchurl { inherit (spec) url sha256; name = name'; }
-      else
-        pkgs.fetchurl { inherit (spec) url sha256; name = name'; };
-
-  fetch_tarball = pkgs: name: spec:
-    let
-      name' = sanitizeName name + "-src";
-    in
-      if spec.builtin or true then
-        builtins_fetchTarball { name = name'; inherit (spec) url sha256; }
-      else
-        pkgs.fetchzip { name = name'; inherit (spec) url sha256; };
-
-  fetch_git = name: spec:
-    let
-      ref =
-        if spec ? ref then spec.ref else
-          if spec ? branch then "refs/heads/${spec.branch}" else
-            if spec ? tag then "refs/tags/${spec.tag}" else
-              abort "In git source '${name}': Please specify `ref`, `tag` or `branch`!";
-    in
-      builtins.fetchGit { url = spec.repo; inherit (spec) rev; inherit ref; };
-
-  fetch_local = spec: spec.path;
-
-  fetch_builtin-tarball = name: throw
-    ''[${name}] The niv type "builtin-tarball" is deprecated. You should instead use `builtin = true`.
-        $ niv modify ${name} -a type=tarball -a builtin=true'';
-
-  fetch_builtin-url = name: throw
-    ''[${name}] The niv type "builtin-url" will soon be deprecated. You should instead use `builtin = true`.
-        $ niv modify ${name} -a type=file -a builtin=true'';
-
-  #
-  # Various helpers
-  #
-
-  # https://github.com/NixOS/nixpkgs/pull/83241/files#diff-c6f540a4f3bfa4b0e8b6bafd4cd54e8bR695
-  sanitizeName = name:
-    (
-      concatMapStrings (s: if builtins.isList s then "-" else s)
-        (
-          builtins.split "[^[:alnum:]+._?=-]+"
-            ((x: builtins.elemAt (builtins.match "\\.*(.*)" x) 0) name)
-        )
-    );
-
-  # The set of packages used when specs are fetched using non-builtins.
-  mkPkgs = sources: system:
-    let
-      sourcesNixpkgs =
-        import (builtins_fetchTarball { inherit (sources.nixpkgs) url sha256; }) { inherit system; };
-      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 name spec
-    else if spec.type == "tarball" then fetch_tarball pkgs name spec
-    else if spec.type == "git" then fetch_git name spec
-    else if spec.type == "local" then fetch_local spec
-    else if spec.type == "builtin-tarball" then fetch_builtin-tarball name
-    else if spec.type == "builtin-url" then fetch_builtin-url name
-    else
-      abort "ERROR: niv spec ${name} has unknown type ${builtins.toJSON spec.type}";
-
-  # If the environment variable NIV_OVERRIDE_${name} is set, then use
-  # the path directly as opposed to the fetched source.
-  replace = name: drv:
-    let
-      saneName = stringAsChars (c: if isNull (builtins.match "[a-zA-Z0-9]" c) then "_" else c) name;
-      ersatz = builtins.getEnv "NIV_OVERRIDE_${saneName}";
-    in
-      if ersatz == "" then drv else
-        # this turns the string into an actual Nix path (for both absolute and
-        # relative paths)
-        if builtins.substring 0 1 ersatz == "/" then /. + ersatz else /. + builtins.getEnv "PWD" + "/${ersatz}";
-
-  # 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))
-  );
-
-  # https://github.com/NixOS/nixpkgs/blob/0258808f5744ca980b9a1f24fe0b1e6f0fecee9c/lib/lists.nix#L295
-  range = first: last: if first > last then [] else builtins.genList (n: first + n) (last - first + 1);
-
-  # https://github.com/NixOS/nixpkgs/blob/0258808f5744ca980b9a1f24fe0b1e6f0fecee9c/lib/strings.nix#L257
-  stringToCharacters = s: map (p: builtins.substring p 1 s) (range 0 (builtins.stringLength s - 1));
-
-  # https://github.com/NixOS/nixpkgs/blob/0258808f5744ca980b9a1f24fe0b1e6f0fecee9c/lib/strings.nix#L269
-  stringAsChars = f: s: concatStrings (map f (stringToCharacters s));
-  concatMapStrings = f: list: concatStrings (map f list);
-  concatStrings = builtins.concatStringsSep "";
-
-  # https://github.com/NixOS/nixpkgs/blob/8a9f58a375c401b96da862d969f66429def1d118/lib/attrsets.nix#L331
-  optionalAttrs = cond: as: if cond then as else {};
-
-  # fetchTarball version that is compatible between all the versions of Nix
-  builtins_fetchTarball = { url, name ? null, sha256 }@attrs:
-    let
-      inherit (builtins) lessThan nixVersion fetchTarball;
-    in
-      if lessThan nixVersion "1.12" then
-        fetchTarball ({ inherit url; } // (optionalAttrs (!isNull name) { inherit name; }))
-      else
-        fetchTarball attrs;
-
-  # fetchurl version that is compatible between all the versions of Nix
-  builtins_fetchurl = { url, name ? null, sha256 }@attrs:
-    let
-      inherit (builtins) lessThan nixVersion fetchurl;
-    in
-      if lessThan nixVersion "1.12" then
-        fetchurl ({ inherit url; } // (optionalAttrs (!isNull name) { inherit name; }))
-      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 = replace name (fetch config.pkgs name spec); }
-    ) config.sources;
-
-  # The "config" used by the fetchers
-  mkConfig =
-    { sourcesFile ? if builtins.pathExists ./sources.json then ./sources.json else null
-    , sources ? if isNull sourcesFile then {} else builtins.fromJSON (builtins.readFile sourcesFile)
-    , system ? builtins.currentSystem
-    , pkgs ? mkPkgs sources system
-    }: 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
index e83ccc7..e20f166 100644
--- a/shell.nix
+++ b/shell.nix
@@ -1,45 +1,21 @@
- let
-  sources  = import ./nix/sources.nix;
-  commands = import ./nix/commands.nix;
-
-  nixos    = import sources.nixpkgs  {};
-  darwin   = import sources.darwin   {};
-  unstable = import sources.unstable {};
-
-  pkgs  = if darwin.stdenv.isDarwin then darwin else nixos;
-  tasks = commands {
-    inherit pkgs;
-    inherit unstable;
-  };
-
-  deps = {
-    common =
-      [  pkgs.niv
-      ];
-
-    elixir =
-      [ unstable.elixir
-      ];
-
-    platform =
-      if pkgs.stdenv.isDarwin then
-        [ unstable.darwin.apple_sdk.frameworks.CoreServices
-          unstable.darwin.apple_sdk.frameworks.Foundation
-        ]
-      else if pkgs.stdenv.isLinux then
-        [ pkgs.inotify-tools
-        ]
-      else
-        [];
-  };
-in
-
-pkgs.mkShell {
-  name = "Algae";
-  nativeBuildInputs = builtins.concatLists [
-    deps.common 
-    deps.elixir
-    deps.platform
-    tasks
-  ];
+let
+  nixpkgs = import (fetchTarball {
+    # Run `cachix use jechol` to use compiled binary cache.
+    url = "https://github.com/jechol/nixpkgs/archive/21.11-otp24-no-jit.tar.gz";
+    sha256 = "sha256:1lka707hrnkp70vny99m9fmp4a8136vl7addmpfsdvkwb81d1jk9";
+  }) { };
+  platform = if nixpkgs.stdenv.isDarwin then [
+    nixpkgs.darwin.apple_sdk.frameworks.CoreServices
+    nixpkgs.darwin.apple_sdk.frameworks.Foundation
+  ] else if nixpkgs.stdenv.isLinux then
+    [ nixpkgs.inotify-tools ]
+  else
+    [ ];
+in nixpkgs.mkShell {
+  buildInputs = with nixpkgs;
+    [
+      # OTP
+      erlang
+      elixir
+    ] ++ platform;
 }