diff --git a/flake-parts/formatting.nix b/flake-parts/formatting.nix
index a1b21597..15cbff2c 100644
--- a/flake-parts/formatting.nix
+++ b/flake-parts/formatting.nix
@@ -1,4 +1,4 @@
-{ self
+{ lib
 , inputs
 , ...
 }: {
@@ -9,7 +9,32 @@
     treefmt.projectRootFile = "flake.nix";
     treefmt.flakeCheck = true;
     treefmt.flakeFormatter = true;
-    treefmt.programs.nixpkgs-fmt.enable = true;
     treefmt.programs.shellcheck.enable = true;
+    treefmt.settings.formatter.nix = {
+      command = "sh";
+      options = [
+        "-eucx"
+        ''
+          # First deadnix
+          ${lib.getExe pkgs.deadnix} --edit "$@"
+          # Then nixpkgs-fmt
+          ${lib.getExe pkgs.nixpkgs-fmt} "$@"
+        ''
+        "--" # this argument is ignored by bash
+      ];
+      includes = [ "*.nix" ];
+    };
+    treefmt.settings.formatter.python = {
+      command = "sh";
+      options = [
+        "-eucx"
+        ''
+          ${lib.getExe pkgs.ruff} --fix "$@"
+          ${lib.getExe pkgs.black} "$@"
+        ''
+        "--" # this argument is ignored by bash
+      ];
+      includes = [ "*.py" ];
+    };
   };
 }
diff --git a/flake-parts/pre-commit.nix b/flake-parts/pre-commit.nix
index d44afc88..fd579e9f 100644
--- a/flake-parts/pre-commit.nix
+++ b/flake-parts/pre-commit.nix
@@ -1,4 +1,4 @@
-{ self, ... }: {
+{ ... }: {
   pre-commit.settings.hooks.alejandra.enable = true;
   pre-commit.settings.hooks.shellcheck.enable = true;
 }
diff --git a/flake.nix b/flake.nix
index 77741213..be2d9834 100644
--- a/flake.nix
+++ b/flake.nix
@@ -14,7 +14,6 @@
   outputs = inputs @ { flake-parts, ... }:
     flake-parts.lib.mkFlake { inherit inputs; } ({ lib
                                                  , config
-                                                 , self
                                                  , ...
                                                  }: {
       systems = lib.systems.flakeExposed;
@@ -22,6 +21,7 @@
         ./flake-parts/packages.nix
         ./flake-parts/formatting.nix
         ./templates/python-project/flake-module.nix
+        ./pkgs/clan-cli/flake-module.nix
       ];
       flake = {
         nixosConfigurations.installer = lib.nixosSystem {
diff --git a/installer.nix b/installer.nix
index 8da5d50f..2daef898 100644
--- a/installer.nix
+++ b/installer.nix
@@ -1,5 +1,4 @@
-{ config
-, lib
+{ lib
 , pkgs
 , ...
 }: {
diff --git a/pkgs/clan-cli/.envrc b/pkgs/clan-cli/.envrc
new file mode 100644
index 00000000..1d953f4b
--- /dev/null
+++ b/pkgs/clan-cli/.envrc
@@ -0,0 +1 @@
+use nix
diff --git a/pkgs/clan-cli/clan-admin.py b/pkgs/clan-cli/clan-admin.py
deleted file mode 100755
index 9ec28898..00000000
--- a/pkgs/clan-cli/clan-admin.py
+++ /dev/null
@@ -1,122 +0,0 @@
-# !/usr/bin/env python3
-import argparse
-import os
-import subprocess
-
-
-def create(args):
-    os.makedirs(args.folder, exist_ok=True)
-    # TODO create clan template in flake
-    subprocess.Popen(
-        [
-            "nix",
-            "flake",
-            "init",
-            "-t",
-            "git+https://git.clan.lol/clan/clan-core#clan-template",
-        ]
-    )
-
-
-def edit(args):
-    # TODO add some cli options to change certain options without relying on a text editor
-    clan_flake = f"{args.folder}/flake.nix"
-    if os.path.isfile(clan_flake):
-        subprocess.Popen(
-            [
-                os.environ["EDITOR"],
-                clan_flake,
-            ]
-        )
-    else:
-        print(
-            f"{args.folder} has no flake.nix, so it does not seem to be the clan root folder"
-        )
-
-
-def rebuild(args):
-    # TODO get clients from zerotier cli?
-    if args.host:
-        print(f"would redeploy {args.host} from clan {args.folder}")
-    else:
-        print(f"would redeploy all hosts from clan {args.folder}")
-
-
-def destroy(args):
-    # TODO get clan folder & hosts from somwhere (maybe ~/.config/clan/$name /)
-    # send some kind of kill signal, then remove the folder
-    if args.yes:
-        print(f"would remove {args.folder}")
-    else:
-        print(
-            "are you really sure? this is non reversible and destructive, add --yes to confirm"
-        )
-
-
-def backup(args):
-    if args.host:
-        print(f"would backup {args.host} from clan {args.folder}")
-    else:
-        print(f"would backup all hosts from clan {args.folder}")
-
-
-def git(args):
-    subprocess.Popen(
-        [
-            "git",
-            "-C",
-            args.folder,
-        ] + args.git_args
-    )
-
-
-parser = argparse.ArgumentParser(description="clan-admin")
-parser.add_argument(
-    "-f",
-    "--folder",
-    help="the folder where the clan is defined, default to the current folder",
-    default=os.environ["PWD"],
-)
-subparser = parser.add_subparsers(
-    title="command",
-    description="the command to run",
-    help="the command to run",
-    required=True,
-)
-
-parser_create = subparser.add_parser("create", help="create a new clan")
-parser_create.set_defaults(func=create)
-
-parser_edit = subparser.add_parser("edit", help="edit a clan")
-parser_edit.set_defaults(func=edit)
-
-parser_rebuild = subparser.add_parser(
-    "rebuild", help="build configuration of a clan and push it to the target"
-)
-parser_rebuild.add_argument(
-    "--host", help="specify single host to rebuild", default=None
-)
-parser_rebuild.set_defaults(func=rebuild)
-
-parser_destroy = subparser.add_parser(
-    "destroy", help="destroy a clan, including all the machines"
-)
-parser_destroy.add_argument(
-    "--yes", help="specify single host to rebuild", action="store_true"
-)
-parser_destroy.set_defaults(func=destroy)
-
-parser_backup = subparser.add_parser(
-    "backup", help="backup all the state of all machines in a clan or just a single one"
-)
-parser_backup.add_argument(
-    "--host", help="specify single host to rebuild", default=None
-)
-parser_backup.set_defaults(func=backup)
-
-parser_git = subparser.add_parser("git", help="control the clan repo via git")
-parser_git.add_argument("git_args", nargs="*")
-parser_git.set_defaults(func=git)
-
-args = parser.parse_args()
-args.func(args)
diff --git a/pkgs/clan-cli/clan.py b/pkgs/clan-cli/clan.py
index 8528c2b0..45261fb4 100755
--- a/pkgs/clan-cli/clan.py
+++ b/pkgs/clan-cli/clan.py
@@ -1,24 +1,26 @@
 # !/usr/bin/env python3
+import argparse
 import sys
-import subprocess
-
-
-def showhelp():
-    print('''
-    usage:
-    clan admin ...
-    clan join ...
-    clan delete ...
-    ''')
-
 
+has_argcomplete = True
 try:
-    cmd = f'clan-{sys.argv[1]}'
-except:  # noqa
-    showhelp()
+    import argcomplete
+except ImportError:
+    has_argcomplete = False
 
-try:
-    subprocess.Popen([cmd] + sys.argv[2:])
-except FileNotFoundError:
-    print(f'command {cmd} not found')
-    exit(2)
+import clan_admin
+
+
+# this will be the entrypoint under /bin/clan (see pyproject.toml config)
+def clan() -> None:
+    parser = argparse.ArgumentParser(description="cLAN tool")
+    subparsers = parser.add_subparsers()
+
+    # init clan admin
+    parser_admin = subparsers.add_parser("admin")
+    clan_admin.make_parser(parser_admin)
+    if has_argcomplete:
+        argcomplete.autocomplete(parser)
+    parser.parse_args()
+    if len(sys.argv) == 1:
+        parser.print_help()
diff --git a/pkgs/clan-cli/clan_admin.py b/pkgs/clan-cli/clan_admin.py
new file mode 100755
index 00000000..7b216fcf
--- /dev/null
+++ b/pkgs/clan-cli/clan_admin.py
@@ -0,0 +1,129 @@
+# !/usr/bin/env python3
+import argparse
+import os
+import subprocess
+
+
+def create(args: argparse.Namespace) -> None:
+    os.makedirs(args.folder, exist_ok=True)
+    # TODO create clan template in flake
+    subprocess.Popen(
+        [
+            "nix",
+            "flake",
+            "init",
+            "-t",
+            "git+https://git.clan.lol/clan/clan-core#clan-template",
+        ]
+    )
+
+
+def edit(args: argparse.Namespace) -> None:  # pragma: no cover
+    # TODO add some cli options to change certain options without relying on a text editor
+    clan_flake = f"{args.folder}/flake.nix"
+    if os.path.isfile(clan_flake):
+        subprocess.Popen(
+            [
+                os.environ["EDITOR"],
+                clan_flake,
+            ]
+        )
+    else:
+        print(
+            f"{args.folder} has no flake.nix, so it does not seem to be the clan root folder",
+        )
+
+
+def rebuild(args: argparse.Namespace) -> None: # pragma: no cover
+    # TODO get clients from zerotier cli?
+    if args.host:
+        print(f"would redeploy {args.host} from clan {args.folder}")
+    else:
+        print(f"would redeploy all hosts from clan {args.folder}")
+
+
+def destroy(args: argparse.Namespace) -> None: # pragma: no cover
+    # TODO get clan folder & hosts from somwhere (maybe ~/.config/clan/$name /)
+    # send some kind of kill signal, then remove the folder
+    if args.yes:
+        print(f"would remove {args.folder}")
+    else:
+        print(
+            "are you really sure? this is non reversible and destructive, add --yes to confirm"
+        )
+
+
+def backup(args: argparse.Namespace) -> None: # pragma: no cover
+    if args.host:
+        print(f"would backup {args.host} from clan {args.folder}")
+    else:
+        print(f"would backup all hosts from clan {args.folder}")
+
+
+def git(args: argparse.Namespace) -> None: # pragma: no cover
+    subprocess.Popen(
+        [
+            "git",
+            "-C",
+            args.folder,
+        ] + args.git_args
+    )
+
+# takes a (sub)parser and configures it
+def make_parser(parser: argparse.ArgumentParser) -> None:
+    parser.add_argument(
+        "-f",
+        "--folder",
+        help="the folder where the clan is defined, default to the current folder",
+        default=os.environ["PWD"],
+    )
+    subparser = parser.add_subparsers(
+        title="command",
+        description="the command to run",
+        help="the command to run",
+        required=True,
+    )
+
+    parser_create = subparser.add_parser("create", help="create a new clan")
+    parser_create.set_defaults(func=create)
+
+    parser_edit = subparser.add_parser("edit", help="edit a clan")
+    parser_edit.set_defaults(func=edit)
+
+    parser_rebuild = subparser.add_parser(
+        "rebuild", help="build configuration of a clan and push it to the target"
+    )
+    parser_rebuild.add_argument(
+        "--host", help="specify single host to rebuild", default=None
+    )
+    parser_rebuild.set_defaults(func=rebuild)
+
+    parser_destroy = subparser.add_parser(
+        "destroy", help="destroy a clan, including all the machines"
+    )
+    parser_destroy.add_argument(
+        "--yes", help="specify single host to rebuild", action="store_true"
+    )
+    parser_destroy.set_defaults(func=destroy)
+
+    parser_backup = subparser.add_parser(
+        "backup", help="backup all the state of all machines in a clan or just a single one"
+    )
+    parser_backup.add_argument(
+        "--host", help="specify single host to rebuild", default=None
+    )
+    parser_backup.set_defaults(func=backup)
+
+    parser_git = subparser.add_parser("git", help="control the clan repo via git")
+    parser_git.add_argument("git_args", nargs="*")
+    parser_git.set_defaults(func=git)
+
+
+def clan_admin() -> None: # pragma: no cover
+    parser = argparse.ArgumentParser(description="clan-admin")
+    args = parser.parse_args()
+    args.func(args)
+
+# entry point if this file is executed directly
+if __name__ == "__main__": # pragma: no cover
+    clan_admin()
diff --git a/pkgs/clan-cli/default.nix b/pkgs/clan-cli/default.nix
index 72214801..74e88d5b 100644
--- a/pkgs/clan-cli/default.nix
+++ b/pkgs/clan-cli/default.nix
@@ -1,10 +1,71 @@
-{ symlinkJoin
-, writers
+{ pkgs ? import <nixpkgs> { }
+, lib ? pkgs.lib
+, python3 ? pkgs.python3
+, ruff ? pkgs.ruff
+, runCommand ? pkgs.runCommand
+, installShellFiles ? pkgs.installShellFiles
+,
 }:
-symlinkJoin {
-  name = "clan";
-  paths = [
-    (writers.writePython3Bin "clan" { } ./clan.py)
-    (writers.writePython3Bin "clan-admin" { flakeIgnore = [ "E501" ]; } ./clan-admin.py)
-  ];
-}
+let
+  pyproject = builtins.fromTOML (builtins.readFile ./pyproject.toml);
+  name = pyproject.project.name;
+
+  src = lib.cleanSource ./.;
+
+  dependencies = lib.attrValues {
+    inherit (python3.pkgs)
+      argcomplete
+      ;
+  };
+
+  devDependencies = lib.attrValues {
+    inherit (pkgs) ruff;
+    inherit (python3.pkgs)
+      black
+      mypy
+      pytest
+      pytest-cov
+      pytest-subprocess
+      setuptools
+      wheel
+      ;
+  };
+
+  package = python3.pkgs.buildPythonPackage {
+    inherit name src;
+    format = "pyproject";
+    nativeBuildInputs = [
+      python3.pkgs.setuptools
+      installShellFiles
+    ];
+    propagatedBuildInputs =
+      dependencies
+      ++ [ ];
+    passthru.tests = { inherit check; };
+    passthru.devDependencies = devDependencies;
+    postInstall = ''
+      installShellCompletion --bash --name clan \
+        <(${python3.pkgs.argcomplete}/bin/register-python-argcomplete --shell bash clan)
+      installShellCompletion --fish --name clan.fish \
+        <(${python3.pkgs.argcomplete}/bin/register-python-argcomplete --shell fish clan)
+    '';
+  };
+
+  checkPython = python3.withPackages (_ps: devDependencies ++ dependencies);
+
+  check = runCommand "${name}-check" { } ''
+    cp -r ${src} ./src
+    chmod +w -R ./src
+    cd src
+    export PYTHONPATH=.
+    echo -e "\x1b[32m## run ruff\x1b[0m"
+    ${ruff}/bin/ruff check .
+    echo -e "\x1b[32m## run mypy\x1b[0m"
+    ${checkPython}/bin/mypy .
+    echo -e "\x1b[32m## run pytest\x1b[0m"
+    ${checkPython}/bin/pytest
+    touch $out
+  '';
+
+in
+package
diff --git a/pkgs/clan-cli/flake-module.nix b/pkgs/clan-cli/flake-module.nix
new file mode 100644
index 00000000..6426e481
--- /dev/null
+++ b/pkgs/clan-cli/flake-module.nix
@@ -0,0 +1,12 @@
+{
+  perSystem = { pkgs, ... }:
+    let
+      pyproject = builtins.fromTOML (builtins.readFile ./pyproject.toml);
+      name = pyproject.project.name;
+      package = pkgs.callPackage ./default.nix { };
+    in
+    {
+      packages.${name} = package;
+      checks.${name} = package.tests.check;
+    };
+}
diff --git a/pkgs/clan-cli/pyproject.toml b/pkgs/clan-cli/pyproject.toml
new file mode 100644
index 00000000..33d3eb4f
--- /dev/null
+++ b/pkgs/clan-cli/pyproject.toml
@@ -0,0 +1,65 @@
+[build-system]
+requires = ["setuptools"]
+build-backend = "setuptools.build_meta"
+
+[tool.setuptools.packages.find]
+include = ["clan.py"]
+
+[project]
+name = "clan"
+description = "cLAN CLI tool"
+dynamic = ["version"]
+scripts = {clan = "clan:clan"}
+
+[tool.pytest.ini_options]
+addopts = "--cov . --cov-report term --cov-fail-under=100 --no-cov-on-fail"
+
+[tool.mypy]
+python_version = "3.10"
+warn_redundant_casts = true
+disallow_untyped_calls = true
+disallow_untyped_defs = true
+no_implicit_optional = true
+exclude = [
+  "tests"
+]
+
+[[tool.mypy.overrides]]
+module = "setuptools.*"
+ignore_missing_imports = true
+
+[[tool.mypy.overrides]]
+module = "pytest.*"
+ignore_missing_imports = true
+
+[[tool.mypy.overrides]]
+module = "argcomplete.*"
+ignore_missing_imports = true
+
+[tool.ruff]
+line-length = 88
+
+select = ["E", "F", "I"]
+ignore = [ "E501" ]
+
+[tool.black]
+line-length = 88
+target-version = ['py310']
+include = '\.pyi?$'
+exclude = '''
+/(
+    \.git
+  | \.hg
+  | \.mypy_cache
+  | \.tox
+  | \.venv
+  | _build
+  | buck-out
+  | build
+  | dist
+  # The following are specific to Black, you probably don't want those.
+  | blib2to3
+  | tests/data
+  | profiling
+)/
+'''
diff --git a/pkgs/clan-cli/shell.nix b/pkgs/clan-cli/shell.nix
new file mode 100644
index 00000000..79cb983b
--- /dev/null
+++ b/pkgs/clan-cli/shell.nix
@@ -0,0 +1,55 @@
+{ pkgs ? import <nixpkgs> { }
+,
+}:
+let
+  lib = pkgs.lib;
+  python3 = pkgs.python3;
+  package = import ./default.nix {
+    inherit lib python3;
+  };
+  pythonWithDeps = python3.withPackages (
+    ps:
+    package.propagatedBuildInputs
+    ++ package.devDependencies
+    ++ [
+      ps.pip
+    ]
+  );
+  checkScript = pkgs.writeScriptBin "check" ''
+    nix build -f . tests.check -L "$@"
+  '';
+  devShell = pkgs.mkShell {
+    packages = [
+      pkgs.ruff
+      pythonWithDeps
+    ];
+    # sets up an editable install and add enty points to $PATH
+    shellHook = ''
+      tmp_path=$(realpath ./.pythonenv)
+      repo_root=$(realpath .)
+      rm -rf $tmp_path
+      mkdir -p "$tmp_path/${pythonWithDeps.sitePackages}"
+
+      ${pythonWithDeps.interpreter} -m pip install \
+        --quiet \
+        --disable-pip-version-check \
+        --no-index \
+        --no-build-isolation \
+        --prefix "$tmp_path" \
+        --editable $repo_root
+
+      export PATH="$tmp_path/bin:${checkScript}/bin:$PATH"
+      export PYTHONPATH="$repo_root:$tmp_path/${pythonWithDeps.sitePackages}"
+
+      export XDG_DATA_DIRS="$tmp_path/share''${XDG_DATA_DIRS:+:$XDG_DATA_DIRS}"
+      export fish_complete_path="$tmp_path/share/fish/vendor_completions.d''${fish_complete_path:+:$fish_complete_path}"
+      mkdir -p \
+        $tmp_path/share/fish/vendor_completions.d \
+        $tmp_path/share/bash-completion/completions \
+        $tmp_path/share/zsh/site-functions
+      register-python-argcomplete --shell fish clan > $tmp_path/share/fish/vendor_completions.d/clan.fish
+      register-python-argcomplete --shell bash clan > $tmp_path/share/bash-completion/completions/clan
+    '';
+  };
+in
+devShell
diff --git a/pkgs/clan-cli/tests/test_clan_admin.py b/pkgs/clan-cli/tests/test_clan_admin.py
new file mode 100644
index 00000000..4440242b
--- /dev/null
+++ b/pkgs/clan-cli/tests/test_clan_admin.py
@@ -0,0 +1,17 @@
+import argparse
+
+import clan_admin
+
+
+def test_make_parser():
+    parser = argparse.ArgumentParser()
+    clan_admin.make_parser(parser)
+
+# using fp fixture from pytest-subprocess
+def test_create(fp):
+    cmd = ["nix", "flake", "init", "-t", fp.any()]
+    fp.register(cmd)
+    args = argparse.Namespace(folder="./my-clan")
+    clan_admin.create(args)
+    assert fp.call_count(cmd) == 1
+
diff --git a/pkgs/clan-cli/tests/test_cli.py b/pkgs/clan-cli/tests/test_cli.py
new file mode 100644
index 00000000..94d94cce
--- /dev/null
+++ b/pkgs/clan-cli/tests/test_cli.py
@@ -0,0 +1,19 @@
+import sys
+
+import pytest
+
+import clan
+
+
+def test_no_args(capsys):
+    clan.clan()
+    captured = capsys.readouterr()
+    assert captured.out.startswith("usage:")
+
+
+def test_help(capsys, monkeypatch):
+    monkeypatch.setattr(sys, "argv", ["", "--help"])
+    with pytest.raises(SystemExit):
+        clan.clan()
+    captured = capsys.readouterr()
+    assert captured.out.startswith("usage:")
diff --git a/templates/python-project/default.nix b/templates/python-project/default.nix
index 30dae1b7..18fa4c6f 100644
--- a/templates/python-project/default.nix
+++ b/templates/python-project/default.nix
@@ -42,7 +42,7 @@ let
     passthru.devDependencies = devDependencies;
   };
 
-  checkPython = python3.withPackages (ps: devDependencies ++ dependencies);
+  checkPython = python3.withPackages (_ps: devDependencies ++ dependencies);
 
   check = runCommand "${name}-check" { } ''
     cp -r ${src} ./src
diff --git a/templates/python-project/flake-module.nix b/templates/python-project/flake-module.nix
index 74218c6d..cfd5c552 100644
--- a/templates/python-project/flake-module.nix
+++ b/templates/python-project/flake-module.nix
@@ -1,8 +1,6 @@
 {
   perSystem = { pkgs, ... }:
     let
-      pyproject = builtins.fromTOML (builtins.readFile ./pyproject.toml);
-      name = pyproject.project.name;
       package = pkgs.callPackage ./default.nix { };
     in
     {
diff --git a/templates/python-project/shell.nix b/templates/python-project/shell.nix
index 2b7b0748..861fe5ef 100644
--- a/templates/python-project/shell.nix
+++ b/templates/python-project/shell.nix
@@ -1,5 +1,4 @@
 { pkgs ? import <nixpkgs> { }
-, system ? builtins.currentSystem
 ,
 }:
 let