diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index bd4c7f9..aa85067 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -16,11 +16,56 @@ jobs:
           python-version: "3.11"
       - uses: astral-sh/setup-uv@v5
 
-      - name: Install dependencies
-        run: uv pip install --system -e . ruff mypy
+      - name: Install dev dependencies
+        run: uv pip install --system -e ".[dev]"
 
-      - name: Lint with ruff
-        run: ruff check src/
+      - name: Lint with ruff (src + tests)
+        run: ruff check .
+
+      - name: Check formatting with ruff
+        run: ruff format --check .
 
       - name: Type check with mypy
         run: mypy src/
+
+  test:
+    runs-on: ubuntu-latest
+    strategy:
+      fail-fast: false
+      matrix:
+        python-version: ["3.10", "3.11", "3.12"]
+    steps:
+      - uses: actions/checkout@v5
+      - uses: actions/setup-python@v6
+        with:
+          python-version: ${{ matrix.python-version }}
+      - uses: astral-sh/setup-uv@v5
+
+      - name: Install dev dependencies
+        run: uv pip install --system -e ".[dev]"
+
+      - name: Run tests with pytest
+        run: pytest
+
+  build:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v5
+      - uses: actions/setup-python@v6
+        with:
+          python-version: "3.11"
+      - uses: astral-sh/setup-uv@v5
+
+      - name: Install build dependencies
+        run: uv pip install --system -e ".[dev]"
+
+      - name: Build source distribution and wheel
+        run: uv build
+
+      - name: Verify build artifacts
+        run: |
+          ls -l dist/
+          # Smoke test: install the wheel and run the CLI entrypoint
+          uv pip install --system dist/*.whl
+          syskit version
+          syskit --help | head -5
diff --git a/README.md b/README.md
index 8840306..d226770 100644
--- a/README.md
+++ b/README.md
@@ -50,11 +50,19 @@ syskit backup
 ## 🛠 Development
 
 ```bash
-# Install dev dependencies
+# Install dev dependencies (includes ruff, mypy, pytest, build)
 uv pip install -e ".[dev]"
 
 # Run locally
 python -m syskit.cli --help
+
+# Lint + format + type check
+ruff check .
+ruff format .
+mypy src/
+
+# Run tests (works on any OS thanks to mocks)
+pytest
 ```
 
 ## Roadmap
diff --git a/pyproject.toml b/pyproject.toml
index a0eff02..85fceac 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -21,6 +21,14 @@ Homepage = "https://github.com/ledutheo/syskit"
 Repository = "https://github.com/ledutheo/syskit"
 Issues = "https://github.com/ledutheo/syskit/issues"
 
+[project.optional-dependencies]
+dev = [
+    "ruff>=0.11.0",
+    "mypy>=1.15.0",
+    "pytest>=8.3.0",
+    "build>=1.2.0",
+]
+
 [build-system]
 requires = ["hatchling"]
 build-backend = "hatchling.build"
@@ -37,3 +45,9 @@ select = ["E", "F", "I"]
 [tool.mypy]
 python_version = "3.10"
 strict = true
+
+[tool.pytest.ini_options]
+testpaths = ["tests"]
+python_files = ["test_*.py", "*_test.py"]
+addopts = "-q --tb=short"
+filterwarnings = ["ignore::DeprecationWarning"]
diff --git a/src/syskit/__init__.py b/src/syskit/__init__.py
index 563636a..09d01dd 100644
--- a/src/syskit/__init__.py
+++ b/src/syskit/__init__.py
@@ -1,3 +1,9 @@
 """syskit - Modern CLI toolkit for Arch/Manjaro users."""
 
-__version__ = "0.1.0"
+from importlib.metadata import PackageNotFoundError, version
+
+try:
+    __version__ = version("syskit")
+except PackageNotFoundError:
+    # Fallback during development when not installed
+    __version__ = "0.1.0"
diff --git a/src/syskit/cli.py b/src/syskit/cli.py
index a544674..08c9ff1 100644
--- a/src/syskit/cli.py
+++ b/src/syskit/cli.py
@@ -12,6 +12,8 @@
 from rich.panel import Panel
 from rich.table import Table
 
+from syskit import __version__
+
 app = typer.Typer(
     name="syskit",
     help="Modern CLI toolkit for Arch Linux and Manjaro users",
@@ -203,7 +205,7 @@ def backup(
 @app.command()
 def version() -> None:
     """Show syskit version."""
-    console.print("syskit version: [bold cyan]0.1.0[/bold cyan]")
+    console.print(f"syskit version: [bold cyan]{__version__}[/bold cyan]")
 
 
 if __name__ == "__main__":
diff --git a/tests/test_cli.py b/tests/test_cli.py
new file mode 100644
index 0000000..41aa6c0
--- /dev/null
+++ b/tests/test_cli.py
@@ -0,0 +1,252 @@
+"""Tests for syskit CLI using Typer's CliRunner and mocks."""
+
+from __future__ import annotations
+
+import subprocess
+from unittest.mock import MagicMock, patch
+
+import pytest
+from typer.testing import CliRunner
+
+from syskit.cli import app, run_command
+
+runner = CliRunner()
+
+
+def test_version_command():
+    """Basic version command outputs the version string."""
+    result = runner.invoke(app, ["version"])
+    assert result.exit_code == 0
+    assert "syskit version: 0.1.0" in result.output
+
+
+def test_help():
+    """--help should list available commands."""
+    result = runner.invoke(app, ["--help"])
+    assert result.exit_code == 0
+    assert "syskit" in result.output
+    assert "info" in result.output
+    assert "clean" in result.output
+    assert "update" in result.output
+    assert "search" in result.output
+    assert "backup" in result.output
+    assert "version" in result.output
+
+
+@patch("syskit.cli.platform")
+@patch("syskit.cli.run_command")
+@patch("builtins.open")
+def test_info_command(mock_open, mock_run_command, mock_platform):
+    """info command displays system info using platform and mocked commands."""
+    # Platform mocks
+    mock_platform.node.return_value = "testhost"
+    mock_platform.release.return_value = "6.12.1-arch1-1"
+    mock_platform.machine.return_value = "x86_64"
+    mock_platform.python_version.return_value = "3.12.3"
+
+    # /etc/os-release mock
+    mock_file = MagicMock()
+    mock_file.__enter__.return_value = ['PRETTY_NAME="Arch Linux"\n']
+    mock_open.return_value = mock_file
+
+    # Command mocks
+    mock_run_command.side_effect = [
+        "up 1 day, 2 hours",  # uptime
+        (
+            "              total        used        free      shared  "
+            "buff/cache   available\n"
+            "Mem:           31Gi        12Gi        15Gi       123Mi       4.2Gi        18Gi"
+        ),  # free -h
+    ]
+
+    result = runner.invoke(app, ["info"])
+    assert result.exit_code == 0
+    assert "System Information" in result.output
+    assert "testhost" in result.output
+    assert "Arch Linux" in result.output
+    assert "up 1 day" in result.output
+    assert "12Gi" in result.output  # from memory parsing
+
+
+@patch("syskit.cli.run_command")
+def test_clean_dry_run(mock_run):
+    """clean --dry-run should list actions without executing or prompting."""
+    mock_run.return_value = "orphan1\norphan2\norphan3"  # pacman -Qtdq
+
+    result = runner.invoke(app, ["clean", "--dry-run"])
+    assert result.exit_code == 0
+    assert "System Cleanup" in result.output
+    assert "Dry run mode" in result.output
+    assert "orphan packages" in result.output
+    assert "pacman package cache" in result.output
+    # Should not have called the real cleanup commands
+    assert not any("sudo" in str(c) for c in mock_run.call_args_list)
+
+
+@patch("syskit.cli.typer.confirm")
+@patch("syskit.cli.run_command")
+def test_clean_with_confirm_no(mock_run, mock_confirm):
+    """clean (no dry-run) with user saying no aborts."""
+    mock_run.return_value = ""  # no orphans
+    mock_confirm.return_value = False
+
+    result = runner.invoke(app, ["clean"])
+    assert result.exit_code == 0
+    assert "Aborted" in result.output
+    # Real cleanup commands not executed
+    assert "sudo pacman" not in " ".join(str(c) for c in mock_run.call_args_list)
+
+
+@patch("syskit.cli.typer.confirm")
+@patch("syskit.cli.run_command")
+def test_clean_with_confirm_yes(mock_run, mock_confirm):
+    """clean with confirm yes runs the cleanup commands."""
+    mock_run.return_value = ""
+    mock_confirm.return_value = True
+
+    result = runner.invoke(app, ["clean"])
+    assert result.exit_code == 0
+    assert "Running cleanup" in result.output
+    assert "Cleanup completed" in result.output
+    # Check that sudo commands were "called"
+    calls = [str(c) for c in mock_run.call_args_list]
+    assert any("pacman" in c and "-Sc" in c for c in calls)
+    assert any("journalctl" in c for c in calls)
+
+
+@patch("syskit.cli.shutil.which")
+@patch("syskit.cli.run_command")
+def test_update_with_aur_helper(mock_run, mock_which):
+    """update detects yay/paru and runs it."""
+    mock_which.side_effect = lambda x: x == "paru"  # only paru present
+
+    result = runner.invoke(app, ["update"])
+    assert result.exit_code == 0
+    assert "Updating official packages" in result.output
+    assert "Updating AUR packages with paru" in result.output
+    assert "System update completed" in result.output
+
+    # pacman + paru called
+    calls = [str(c) for c in mock_run.call_args_list]
+    assert any("pacman" in c and "-Syu" in c for c in calls)
+    assert any("paru" in c and "-Syu" in c for c in calls)
+
+
+@patch("syskit.cli.shutil.which")
+@patch("syskit.cli.run_command")
+def test_update_no_aur_helper(mock_run, mock_which):
+    """update without AUR helper still succeeds and warns."""
+    mock_which.return_value = None
+
+    result = runner.invoke(app, ["update"])
+    assert result.exit_code == 0
+    assert "No AUR helper found (yay/paru)" in result.output
+    assert "System update completed" in result.output
+
+
+@patch("syskit.cli.run_command")
+def test_search_with_results(mock_run):
+    """search parses pacman -Ss output into a nice table."""
+    mock_run.return_value = (
+        "extra/firefox 128.0-1 [installed]\n"
+        "    Fast, Private and Safe Web Browser\n"
+        "community/vscode 1.90-1\n"
+        "    Code editor\n"
+    )
+
+    result = runner.invoke(app, ["search", "firefox"])
+    assert result.exit_code == 0
+    assert "Searching for: firefox" in result.output
+    assert "firefox" in result.output
+    assert "Fast, Private" in result.output
+
+
+@patch("syskit.cli.run_command")
+def test_search_no_results(mock_run):
+    """search with no/error output shows friendly message."""
+    mock_run.return_value = "Error: nothing found"
+
+    result = runner.invoke(app, ["search", "nonexistentpkg999"])
+    assert result.exit_code == 0
+    assert "No results found" in result.output
+
+
+@patch("syskit.cli.run_command")
+def test_backup_success(mock_run, tmp_path):
+    """backup creates parent dir (via code) and reports size on success."""
+    # Use a temp output so we don't touch real ~
+    backup_file = tmp_path / "backups" / "test-backup.tar.gz"
+    # Simulate successful tar (run_command returns no "Error")
+    mock_run.return_value = ""
+
+    # Create the file so .stat() works in the success branch
+    backup_file.parent.mkdir(parents=True)
+    backup_file.write_bytes(b"x" * 1234567)  # ~1.2 MB
+
+    # Patch the default in the Option? Easier: invoke with explicit --output
+    result = runner.invoke(app, ["backup", "--output", str(backup_file)])
+    assert result.exit_code == 0
+    assert "Creating backup" in result.output
+    assert "Backup created" in result.output
+    assert "MB" in result.output
+
+
+@patch("syskit.cli.run_command")
+def test_backup_failure(mock_run, tmp_path):
+    """backup shows error message when run_command fails."""
+    backup_file = tmp_path / "backup-fail.tar.gz"
+    mock_run.return_value = "Error: tar failed"
+
+    result = runner.invoke(app, ["backup", "--output", str(backup_file)])
+    assert result.exit_code == 0
+    assert "Backup failed" in result.output
+
+
+def test_run_command_success():
+    """run_command returns stripped stdout on success."""
+    with patch("subprocess.run") as mock_run:
+        mock_result = MagicMock()
+        mock_result.stdout = " hello \n world \n"
+        mock_run.return_value = mock_result
+        out = run_command(["echo", "hello"])
+        assert out == "hello \n world"
+        mock_run.assert_called_once()
+
+
+def test_run_command_called_process_error():
+    """run_command returns Error: ... on CalledProcessError."""
+    with patch("subprocess.run") as mock_run:
+        err = subprocess.CalledProcessError(1, ["false"])
+        err.stderr = "some error output"
+        mock_run.side_effect = err
+        out = run_command(["false"])
+        assert out.startswith("Error: some error output")
+
+
+def test_run_command_file_not_found():
+    """run_command handles missing binary gracefully."""
+    with patch("subprocess.run", side_effect=FileNotFoundError()):
+        out = run_command(["nonexistentcmd"])
+        assert "Command not found: nonexistentcmd" in out
+
+
+@pytest.mark.parametrize(
+    "cmd",
+    [
+        "info",
+        "clean",
+        "update",
+        "search foo",
+        "backup --output /tmp/x.tar.gz",
+        "version",
+    ],
+)
+def test_all_commands_have_help_text(cmd):
+    """Smoke test: every command is registered and has a docstring/help."""
+    # Just invoking --help on subcommand or the command itself
+    args = cmd.split() + ["--help"]
+    result = runner.invoke(app, args)
+    # Some commands show their own help or the global; exit 0 or 2 is fine for --help
+    assert (
+        "Usage:" in result.output or "help" in result.output.lower() or result.exit_code in (0, 2)
+    )