[nix] Use niv and poetry2nix to more easily manage dependencies (#11181)

* [nix] Update nixpkgs to avoid issues with Big Sur

The older nixpkgs snapshot did not contain nix changes to the
compiler/linker hooks that are necessary for compatibility with MacOS
Big Sur. The fix is simply to update to a newer snapshot.

* [nix] Add a poetry manifest and use poetry to build the Python env

* [nix] Use niv to manage upstream sources like nixpkgs

* [nix] Update to newer nixpkgs snapshot

* [nix] Bump python package versions

6 files changed, 611 insertions, 24 deletions

diff --git a/.gitattributes b/.gitattributes
index 92dfc3c617..a0fd4fed62 100644
--- a/.gitattributes
+++ b/.gitattributes
@@ -92,3 +92,4 @@ GRAPHICS
 # hex files
 *.hex binary
 *.eep binary
+nix/sources.nix linguist-generated=true
diff --git a/nix/poetry.lock b/nix/poetry.lock
new file mode 100644
index 0000000000..74d6e7dd58
--- /dev/null
+++ b/nix/poetry.lock
@@ -0,0 +1,369 @@
+[[package]]
+name = "appdirs"
+version = "1.4.4"
+description = "A small Python module for determining appropriate platform-specific dirs, e.g. a \"user data dir\"."
+category = "main"
+optional = false
+python-versions = "*"
+
+[[package]]
+name = "argcomplete"
+version = "1.12.2"
+description = "Bash tab completion for argparse"
+category = "main"
+optional = false
+python-versions = "*"
+
+[package.extras]
+test = ["coverage", "flake8", "pexpect", "wheel"]
+
+[[package]]
+name = "attrs"
+version = "20.3.0"
+description = "Classes Without Boilerplate"
+category = "main"
+optional = false
+python-versions = ">=2.7, !=3.0.*, !=3.1.*, !=3.2.*, !=3.3.*"
+
+[package.extras]
+dev = ["coverage[toml] (>=5.0.2)", "hypothesis", "pympler", "pytest (>=4.3.0)", "six", "zope.interface", "furo", "sphinx", "pre-commit"]
+docs = ["furo", "sphinx", "zope.interface"]
+tests = ["coverage[toml] (>=5.0.2)", "hypothesis", "pympler", "pytest (>=4.3.0)", "six", "zope.interface"]
+tests_no_zope = ["coverage[toml] (>=5.0.2)", "hypothesis", "pympler", "pytest (>=4.3.0)", "six"]
+
+[[package]]
+name = "colorama"
+version = "0.4.4"
+description = "Cross-platform colored terminal text."
+category = "main"
+optional = false
+python-versions = ">=2.7, !=3.0.*, !=3.1.*, !=3.2.*, !=3.3.*, !=3.4.*"
+
+[[package]]
+name = "coverage"
+version = "5.5"
+description = "Code coverage measurement for Python"
+category = "dev"
+optional = false
+python-versions = ">=2.7, !=3.0.*, !=3.1.*, !=3.2.*, !=3.3.*, !=3.4.*, <4"
+
+[package.extras]
+toml = ["toml"]
+
+[[package]]
+name = "dotty-dict"
+version = "1.3.0"
+description = "Dictionary wrapper for quick access to deeply nested keys."
+category = "main"
+optional = false
+python-versions = "*"
+
+[package.dependencies]
+setuptools_scm = "*"
+
+[[package]]
+name = "flake8"
+version = "3.9.0"
+description = "the modular source code checker: pep8 pyflakes and co"
+category = "dev"
+optional = false
+python-versions = "!=3.0.*,!=3.1.*,!=3.2.*,!=3.3.*,!=3.4.*,>=2.7"
+
+[package.dependencies]
+mccabe = ">=0.6.0,<0.7.0"
+pycodestyle = ">=2.7.0,<2.8.0"
+pyflakes = ">=2.3.0,<2.4.0"
+
+[[package]]
+name = "flake8-polyfill"
+version = "1.0.2"
+description = "Polyfill package for Flake8 plugins"
+category = "dev"
+optional = false
+python-versions = "*"
+
+[package.dependencies]
+flake8 = "*"
+
+[[package]]
+name = "hjson"
+version = "3.0.2"
+description = "Hjson, a user interface for JSON."
+category = "main"
+optional = false
+python-versions = "*"
+
+[[package]]
+name = "jsonschema"
+version = "3.2.0"
+description = "An implementation of JSON Schema validation for Python"
+category = "main"
+optional = false
+python-versions = "*"
+
+[package.dependencies]
+attrs = ">=17.4.0"
+pyrsistent = ">=0.14.0"
+six = ">=1.11.0"
+
+[package.extras]
+format = ["idna", "jsonpointer (>1.13)", "rfc3987", "strict-rfc3339", "webcolors"]
+format_nongpl = ["idna", "jsonpointer (>1.13)", "webcolors", "rfc3986-validator (>0.1.0)", "rfc3339-validator"]
+
+[[package]]
+name = "mccabe"
+version = "0.6.1"
+description = "McCabe checker, plugin for flake8"
+category = "dev"
+optional = false
+python-versions = "*"
+
+[[package]]
+name = "milc"
+version = "1.3.0"
+description = "Opinionated Batteries-Included Python 3 CLI Framework."
+category = "main"
+optional = false
+python-versions = "*"
+
+[package.dependencies]
+appdirs = "*"
+argcomplete = "*"
+colorama = "*"
+
+[[package]]
+name = "nose2"
+version = "0.10.0"
+description = "unittest2 with plugins, the succesor to nose"
+category = "dev"
+optional = false
+python-versions = "*"
+
+[package.dependencies]
+coverage = ">=4.4.1"
+six = ">=1.7"
+
+[package.extras]
+coverage_plugin = ["coverage (>=4.4.1)"]
+dev = ["Sphinx (>=1.6.5)", "sphinx-rtd-theme", "mock", "coverage"]
+
+[[package]]
+name = "pep8-naming"
+version = "0.11.1"
+description = "Check PEP-8 naming conventions, plugin for flake8"
+category = "dev"
+optional = false
+python-versions = "*"
+
+[package.dependencies]
+flake8-polyfill = ">=1.0.2,<2"
+
+[[package]]
+name = "pycodestyle"
+version = "2.7.0"
+description = "Python style guide checker"
+category = "dev"
+optional = false
+python-versions = ">=2.7, !=3.0.*, !=3.1.*, !=3.2.*, !=3.3.*"
+
+[[package]]
+name = "pyflakes"
+version = "2.3.1"
+description = "passive checker of Python programs"
+category = "dev"
+optional = false
+python-versions = ">=2.7, !=3.0.*, !=3.1.*, !=3.2.*, !=3.3.*"
+
+[[package]]
+name = "pygments"
+version = "2.8.1"
+description = "Pygments is a syntax highlighting package written in Python."
+category = "main"
+optional = false
+python-versions = ">=3.5"
+
+[[package]]
+name = "pyrsistent"
+version = "0.17.3"
+description = "Persistent/Functional/Immutable data structures"
+category = "main"
+optional = false
+python-versions = ">=3.5"
+
+[[package]]
+name = "setuptools-scm"
+version = "6.0.1"
+description = "the blessed package to manage your versions by scm tags"
+category = "main"
+optional = false
+python-versions = ">=3.6"
+
+[package.extras]
+toml = ["toml"]
+
+[[package]]
+name = "six"
+version = "1.15.0"
+description = "Python 2 and 3 compatibility utilities"
+category = "main"
+optional = false
+python-versions = ">=2.7, !=3.0.*, !=3.1.*, !=3.2.*"
+
+[[package]]
+name = "wave"
+version = "0.0.2"
+description = "Whole Architecture Verification"
+category = "dev"
+optional = false
+python-versions = "*"
+
+[[package]]
+name = "yapf"
+version = "0.30.0"
+description = "A formatter for Python code."
+category = "dev"
+optional = false
+python-versions = "*"
+
+[metadata]
+lock-version = "1.1"
+python-versions = "^3.8"
+content-hash = "6adb87c61d9eacf55e4e80bc6c73325e4e4854a792e3881ff448b6ee1cb75091"
+
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+jsonschema = [
+    {file = "jsonschema-3.2.0-py2.py3-none-any.whl", hash = "sha256:4e5b3cf8216f577bee9ce139cbe72eca3ea4f292ec60928ff24758ce626cd163"},
+    {file = "jsonschema-3.2.0.tar.gz", hash = "sha256:c8a85b28d377cc7737e46e2d9f2b4f44ee3c0e1deac6bf46ddefc7187d30797a"},
+]
+mccabe = [
+    {file = "mccabe-0.6.1-py2.py3-none-any.whl", hash = "sha256:ab8a6258860da4b6677da4bd2fe5dc2c659cff31b3ee4f7f5d64e79735b80d42"},
+    {file = "mccabe-0.6.1.tar.gz", hash = "sha256:dd8d182285a0fe56bace7f45b5e7d1a6ebcbf524e8f3bd87eb0f125271b8831f"},
+]
+milc = [
+    {file = "milc-1.3.0-py2.py3-none-any.whl", hash = "sha256:a4dd8ce77f1d4ac5e08311eecc6954c349d4032d7ed4e0335822e09740514f22"},
+    {file = "milc-1.3.0.tar.gz", hash = "sha256:a9d0299aaaef7a3f00010589c3c0d0669798467e397580620a68e9290b36cdda"},
+]
+nose2 = [
+    {file = "nose2-0.10.0-py2.py3-none-any.whl", hash = "sha256:aa620e759f2c5018d9ba041340391913e282ecebd3c392027f1575847b093ec6"},
+    {file = "nose2-0.10.0.tar.gz", hash = "sha256:886ba617a96de0130c54b24479bd5c2d74d5c940d40f3809c3a275511a0c4a60"},
+]
+pep8-naming = [
+    {file = "pep8-naming-0.11.1.tar.gz", hash = "sha256:a1dd47dd243adfe8a83616e27cf03164960b507530f155db94e10b36a6cd6724"},
+    {file = "pep8_naming-0.11.1-py2.py3-none-any.whl", hash = "sha256:f43bfe3eea7e0d73e8b5d07d6407ab47f2476ccaeff6937c84275cd30b016738"},
+]
+pycodestyle = [
+    {file = "pycodestyle-2.7.0-py2.py3-none-any.whl", hash = "sha256:514f76d918fcc0b55c6680472f0a37970994e07bbb80725808c17089be302068"},
+    {file = "pycodestyle-2.7.0.tar.gz", hash = "sha256:c389c1d06bf7904078ca03399a4816f974a1d590090fecea0c63ec26ebaf1cef"},
+]
+pyflakes = [
+    {file = "pyflakes-2.3.1-py2.py3-none-any.whl", hash = "sha256:7893783d01b8a89811dd72d7dfd4d84ff098e5eed95cfa8905b22bbffe52efc3"},
+    {file = "pyflakes-2.3.1.tar.gz", hash = "sha256:f5bc8ecabc05bb9d291eb5203d6810b49040f6ff446a756326104746cc00c1db"},
+]
+pygments = [
+    {file = "Pygments-2.8.1-py3-none-any.whl", hash = "sha256:534ef71d539ae97d4c3a4cf7d6f110f214b0e687e92f9cb9d2a3b0d3101289c8"},
+    {file = "Pygments-2.8.1.tar.gz", hash = "sha256:2656e1a6edcdabf4275f9a3640db59fd5de107d88e8663c5d4e9a0fa62f77f94"},
+]
+pyrsistent = [
+    {file = "pyrsistent-0.17.3.tar.gz", hash = "sha256:2e636185d9eb976a18a8a8e96efce62f2905fea90041958d8cc2a189756ebf3e"},
+]
+setuptools-scm = [
+    {file = "setuptools_scm-6.0.1-py3-none-any.whl", hash = "sha256:c3bd5f701c8def44a5c0bfe8d407bef3f80342217ef3492b951f3777bd2d915c"},
+    {file = "setuptools_scm-6.0.1.tar.gz", hash = "sha256:d1925a69cb07e9b29416a275b9fadb009a23c148ace905b2fb220649a6c18e92"},
+]
+six = [
+    {file = "six-1.15.0-py2.py3-none-any.whl", hash = "sha256:8b74bedcbbbaca38ff6d7491d76f2b06b3592611af620f8426e82dddb04a5ced"},
+    {file = "six-1.15.0.tar.gz", hash = "sha256:30639c035cdb23534cd4aa2dd52c3bf48f06e5f4a941509c8bafd8ce11080259"},
+]
+wave = [
+    {file = "Wave-0.0.2.tar.gz", hash = "sha256:5a895bb85e04e38c82dba90d66a5ae8f488b50c58f3fc4df868a5bcdcabb8632"},
+    {file = "Wave-0.0.2.zip", hash = "sha256:5187f49497287d218cc83d4cd1e5299dc31485ab3ed32abbaa9e95d8f73c4095"},
+]
+yapf = [
+    {file = "yapf-0.30.0-py2.py3-none-any.whl", hash = "sha256:3abf61ba67cf603069710d30acbc88cfe565d907e16ad81429ae90ce9651e0c9"},
+    {file = "yapf-0.30.0.tar.gz", hash = "sha256:3000abee4c28daebad55da6c85f3cd07b8062ce48e2e9943c8da1b9667d48427"},
+]
diff --git a/nix/pyproject.toml b/nix/pyproject.toml
new file mode 100644
index 0000000000..62d49fad59
--- /dev/null
+++ b/nix/pyproject.toml
@@ -0,0 +1,30 @@
+# This file should be kept in sync with requirements.txt and requirements-dev.txt
+# It is particularly required by the Nix environment (see shell.nix). To update versions,
+# normally one would run "poetry update --lock"
+[tool.poetry]
+name = "qmk"
+version = "0.1.0"
+description = ""
+authors = []
+
+[tool.poetry.dependencies]
+python = "^3.8"
+appdirs = "^1.4.4"
+argcomplete = "^1.12.2"
+colorama = "^0.4.4"
+hjson = "^3.0.2"
+milc = "^1.1.0"
+Pygments = "^2.8.0"
+dotty-dict = "^1.3.0"
+jsonschema = "^3.2.0"
+
+[tool.poetry.dev-dependencies]
+nose2 = "^0.10.0"
+flake8 = "^3.8.4"
+pep8-naming = "^0.11.1"
+yapf = "^0.30.0"
+Wave = "^0.0.2"
+
+[build-system]
+requires = ["poetry-core>=1.0.0"]
+build-backend = "poetry.core.masonry.api"
diff --git a/nix/sources.json b/nix/sources.json
new file mode 100644
index 0000000000..7afca37073
--- /dev/null
+++ b/nix/sources.json
@@ -0,0 +1,26 @@
+{
+    "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": "nixpkgs-unstable",
+        "description": "Nix Packages collection",
+        "homepage": "",
+        "owner": "NixOS",
+        "repo": "nixpkgs",
+        "rev": "c0e881852006b132236cbf0301bd1939bb50867e",
+        "sha256": "0fy7z7yxk5n7yslsvx5cyc6h21qwi4bhxf3awhirniszlbvaazy2",
+        "type": "tarball",
+        "url": "https://github.com/NixOS/nixpkgs/archive/c0e881852006b132236cbf0301bd1939bb50867e.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 0000000000..1938409ddd
--- /dev/null
+++ b/nix/sources.nix
@@ -0,0 +1,174 @@
+# 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 ab44dd8e31..e82436ae11 100644
--- a/shell.nix
+++ b/shell.nix
@@ -1,29 +1,16 @@
 { avr ? true, arm ? true, teensy ? true }:
-
 let
-  nixpkgs = builtins.fetchTarball {
-    url = "https://github.com/NixOS/nixpkgs/archive/1f77a4c8c74bbe896053994836790aa9bf6dc5ba.tar.gz";
-    sha256 = "1j62nmzz3w33dplzf1xz1pg1pfkxii7lwdqmsxmc71cs9cm3s7n1";
-  };
+  # We specify sources via Niv: use "niv update nixpkgs" to update nixpkgs, for example.
+  sources = import ./nix/sources.nix {};
+  pkgs = import sources.nixpkgs {};
 
-  pkgs = import nixpkgs { };
-
-  pythonEnv = pkgs.python3.withPackages (p: with p; [
-    # requirements.txt
-    appdirs
-    argcomplete
-    colorama
-    dotty-dict
-    hjson
-    jsonschema
-    milc
-    pygments
-    # requirements-dev.txt
-    nose2
-    flake8
-    pep8-naming
-    yapf
-  ]);
+  # Builds the python env based on nix/pyproject.toml and
+  # nix/poetry.lock Use the "poetry update --lock", "poetry add
+  # --lock" etc. in the nix folder to adjust the contents of those
+  # files if the requirements*.txt files change
+  pythonEnv = pkgs.poetry2nix.mkPoetryEnv {
+    projectDir = ./nix;
+  };
 in
 
 with pkgs;
@@ -43,7 +30,7 @@ in
 mkShell {
   name = "qmk-firmware";
 
-  buildInputs = [ clang-tools dfu-programmer dfu-util diffutils git pythonEnv ]
+  buildInputs = [ clang-tools dfu-programmer dfu-util diffutils git pythonEnv poetry niv ]
     ++ lib.optional avr [
       pkgsCross.avr.buildPackages.binutils
       pkgsCross.avr.buildPackages.gcc8