diff --git a/app/local_commit_message_generator/tests/test_config.py b/app/local_commit_message_generator/tests/test_config.py
new file mode 100644
index 0000000..12273e4
--- /dev/null
+++ b/app/local_commit_message_generator/tests/test_config.py
@@ -0,0 +1,143 @@
+"""Tests for configuration module."""
+
+import os
+import tempfile
+from pathlib import Path
+from unittest.mock import patch
+
+import pytest
+
+from src.config import (
+    DEFAULT_CONFIG,
+    DEFAULT_TYPE_RULES,
+    get_config_path,
+    load_config,
+    save_config,
+    get_type_rules,
+    get_template,
+    ConfigError,
+)
+
+
+class TestGetConfigPath:
+    """Tests for get_config_path function."""
+
+    def test_returns_home_config(self):
+        """Test that config path is in home directory."""
+        with patch("src.config.Path.home") as mock_home:
+            mock_home.return_value = Path("/home/testuser")
+            result = get_config_path()
+            assert result == Path("/home/testuser/.local_commit_gen.toml")
+
+
+class TestLoadConfig:
+    """Tests for load_config function."""
+
+    def test_loads_default_config_when_no_file(self):
+        """Test that default config is loaded when file doesn't exist."""
+        with tempfile.TemporaryDirectory() as tmpdir:
+            config_path = Path(tmpdir) / "nonexistent.toml"
+            result = load_config(config_path)
+            assert result == DEFAULT_CONFIG
+
+    def test_loads_custom_config(self):
+        """Test loading custom configuration."""
+        with tempfile.TemporaryDirectory() as tmpdir:
+            config_path = Path(tmpdir) / "config.toml"
+            custom_config = """
+template = "{type}: {description}"
+
+[scopes]
+src = "source"
+"""
+            with open(config_path, "w") as f:
+                f.write(custom_config)
+
+            result = load_config(config_path)
+            assert result["template"] == "{type}: {description}"
+            assert result["scopes"]["src"] == "source"
+
+    def test_merges_custom_type_rules(self):
+        """Test that custom type rules are merged with defaults."""
+        with tempfile.TemporaryDirectory() as tmpdir:
+            config_path = Path(tmpdir) / "config.toml"
+            custom_config = """
+[type_rules]
+feat = ["custom/feat/"]
+"""
+            with open(config_path, "w") as f:
+                f.write(custom_config)
+
+            result = load_config(config_path)
+            assert "feat" in result["type_rules"]
+            assert "custom/feat/" in result["type_rules"]["feat"]
+            assert result["type_rules"]["fix"] == DEFAULT_TYPE_RULES["fix"]
+
+    def test_invalid_toml_raises_error(self):
+        """Test that invalid TOML raises ConfigError."""
+        with tempfile.TemporaryDirectory() as tmpdir:
+            config_path = Path(tmpdir) / "invalid.toml"
+            with open(config_path, "w") as f:
+                f.write("invalid = toml = syntax")
+
+            with pytest.raises(ConfigError):
+                load_config(config_path)
+
+
+class TestSaveConfig:
+    """Tests for save_config function."""
+
+    def test_saves_config_to_file(self):
+        """Test saving configuration to file."""
+        with tempfile.TemporaryDirectory() as tmpdir:
+            config_path = Path(tmpdir) / "config.toml"
+            config = {"test": "value", "nested": {"key": "val"}}
+
+            save_config(config, config_path)
+
+            assert config_path.exists()
+            loaded = load_config(config_path)
+            assert loaded["test"] == "value"
+
+    def test_overwrites_existing_config(self):
+        """Test overwriting existing configuration."""
+        with tempfile.TemporaryDirectory() as tmpdir:
+            config_path = Path(tmpdir) / "config.toml"
+            save_config({"old": "value"}, config_path)
+            save_config({"new": "value"}, config_path)
+
+            loaded = load_config(config_path)
+            assert loaded["new"] == "value"
+
+
+class TestGetTypeRules:
+    """Tests for get_type_rules function."""
+
+    def test_returns_rules_from_config(self):
+        """Test returning type rules from config."""
+        custom_rules = {"feat": ["custom/"]}
+        config = {"type_rules": custom_rules}
+        result = get_type_rules(config)
+        assert result["feat"] == ["custom/"]
+
+    def test_returns_default_when_no_config(self):
+        """Test returning default rules when no config provided."""
+        result = get_type_rules()
+        assert "feat" in result
+        assert "fix" in result
+        assert "docs" in result
+
+
+class TestGetTemplate:
+    """Tests for get_template function."""
+
+    def test_returns_template_from_config(self):
+        """Test returning template from config."""
+        config = {"template": "custom: {description}"}
+        result = get_template(config)
+        assert result == "custom: {description}"
+
+    def test_returns_default_when_no_config(self):
+        """Test returning default template when no config provided."""
+        result = get_template()
+        assert result == DEFAULT_CONFIG["template"]