diff --git a/.gitignore b/.gitignore
index 397b4a7..5dc29e8 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1 +1,45 @@
 *.log
+
+# Testing
+.pytest_cache/
+.coverage
+htmlcov/
+coverage.xml
+*.py[cod]
+__pycache__/
+.tox/
+.nox/
+
+# Claude
+.claude/*
+
+# Virtual environments
+venv/
+.venv/
+env/
+ENV/
+.env
+
+# Poetry
+poetry.lock
+
+# IDE
+.vscode/
+.idea/
+*.swp
+*.swo
+*~
+
+# OS
+.DS_Store
+Thumbs.db
+
+# Build artifacts
+build/
+dist/
+*.egg-info/
+.eggs/
+*.egg
+
+# Pipenv (keeping lock file)
+# Pipfile.lock is NOT ignored
diff --git a/pyproject.toml b/pyproject.toml
new file mode 100644
index 0000000..9d7f32a
--- /dev/null
+++ b/pyproject.toml
@@ -0,0 +1,84 @@
+[tool.poetry]
+name = "dnschef"
+version = "0.4"
+description = "A highly configurable DNS Proxy for Penetration Testers and Malware Analysts"
+authors = ["Peter Kacherginsky", "Marcello Salvati"]
+readme = "README"
+homepage = "http://thesprawl.org/projects/dnschef/"
+license = "BSD-3-Clause"
+
+[tool.poetry.dependencies]
+python = "^3.7"
+dnslib = "0.9.10"
+
+[tool.poetry.group.dev.dependencies]
+pytest = "^7.4.0"
+pytest-cov = "^4.1.0"
+pytest-mock = "^3.11.0"
+
+[tool.poetry.scripts]
+test = "pytest:main"
+tests = "pytest:main"
+
+[tool.pytest.ini_options]
+minversion = "6.0"
+addopts = [
+    "-ra",
+    "--strict-markers",
+    "--strict-config",
+    "--cov=dnschef",
+    "--cov-branch",
+    "--cov-report=term-missing:skip-covered",
+    "--cov-report=html",
+    "--cov-report=xml",
+    "--cov-fail-under=80"
+]
+testpaths = ["tests"]
+python_files = ["test_*.py", "*_test.py"]
+python_classes = ["Test*"]
+python_functions = ["test_*"]
+markers = [
+    "unit: Unit tests",
+    "integration: Integration tests",
+    "slow: Tests that take a long time to run"
+]
+
+[tool.coverage.run]
+source = ["dnschef"]
+branch = true
+omit = [
+    "*/tests/*",
+    "*/test_*",
+    "*/__pycache__/*",
+    "*/site-packages/*",
+    "*/venv/*",
+    "*/.venv/*"
+]
+
+[tool.coverage.report]
+exclude_lines = [
+    "pragma: no cover",
+    "def __repr__",
+    "if self.debug:",
+    "if settings.DEBUG",
+    "raise AssertionError",
+    "raise NotImplementedError",
+    "if 0:",
+    "if __name__ == .__main__.:",
+    "if TYPE_CHECKING:",
+    "class .*\\bProtocol\\):",
+    "@(abc\\.)?abstractmethod"
+]
+show_missing = true
+precision = 2
+fail_under = 80
+
+[tool.coverage.html]
+directory = "htmlcov"
+
+[tool.coverage.xml]
+output = "coverage.xml"
+
+[build-system]
+requires = ["poetry-core>=1.0.0"]
+build-backend = "poetry.core.masonry.api"
\ No newline at end of file
diff --git a/tests/__init__.py b/tests/__init__.py
new file mode 100644
index 0000000..e69de29
diff --git a/tests/conftest.py b/tests/conftest.py
new file mode 100644
index 0000000..aee25d5
--- /dev/null
+++ b/tests/conftest.py
@@ -0,0 +1,163 @@
+import pytest
+import tempfile
+import shutil
+import os
+from pathlib import Path
+from unittest.mock import Mock, MagicMock
+
+
+@pytest.fixture
+def temp_dir():
+    """Create a temporary directory for test files."""
+    temp_path = tempfile.mkdtemp()
+    yield Path(temp_path)
+    shutil.rmtree(temp_path)
+
+
+@pytest.fixture
+def temp_file(temp_dir):
+    """Create a temporary file within the temp directory."""
+    def _temp_file(filename="test_file.txt", content=""):
+        file_path = temp_dir / filename
+        file_path.write_text(content)
+        return file_path
+    return _temp_file
+
+
+@pytest.fixture
+def mock_config():
+    """Create a mock configuration object."""
+    config = Mock()
+    config.interface = "127.0.0.1"
+    config.port = 53
+    config.tcp = False
+    config.ipv6 = False
+    config.file = None
+    config.fakedomains = {}
+    config.truedomains = {}
+    config.nameservers = ["8.8.8.8", "8.8.4.4"]
+    return config
+
+
+@pytest.fixture
+def mock_dns_query():
+    """Create a mock DNS query object."""
+    query = Mock()
+    query.questions = [Mock()]
+    query.questions[0].qname = "example.com"
+    query.questions[0].qtype = 1  # A record
+    query.questions[0].qclass = 1  # IN class
+    return query
+
+
+@pytest.fixture
+def mock_socket():
+    """Create a mock socket object."""
+    socket_mock = MagicMock()
+    socket_mock.sendto = Mock(return_value=None)
+    socket_mock.recvfrom = Mock(return_value=(b"mock_response", ("127.0.0.1", 53)))
+    socket_mock.close = Mock(return_value=None)
+    return socket_mock
+
+
+@pytest.fixture
+def mock_logger():
+    """Create a mock logger object."""
+    logger = Mock()
+    logger.info = Mock()
+    logger.debug = Mock()
+    logger.warning = Mock()
+    logger.error = Mock()
+    logger.critical = Mock()
+    return logger
+
+
+@pytest.fixture
+def dns_server_config():
+    """Create a basic DNS server configuration dictionary."""
+    return {
+        "interface": "0.0.0.0",
+        "port": 53,
+        "tcp": False,
+        "ipv6": False,
+        "nameservers": ["8.8.8.8"],
+        "fakedomains": {
+            "example.com": "192.168.1.100"
+        },
+        "truedomains": {}
+    }
+
+
+@pytest.fixture
+def sample_dns_records():
+    """Provide sample DNS records for testing."""
+    return {
+        "A": {
+            "example.com": "192.168.1.1",
+            "test.com": "10.0.0.1"
+        },
+        "AAAA": {
+            "example.com": "2001:db8::1",
+            "test.com": "2001:db8::2"
+        },
+        "MX": {
+            "example.com": "10 mail.example.com",
+            "test.com": "20 mail.test.com"
+        },
+        "CNAME": {
+            "www.example.com": "example.com",
+            "alias.test.com": "test.com"
+        },
+        "NS": {
+            "example.com": "ns1.example.com",
+            "test.com": "ns1.test.com"
+        },
+        "TXT": {
+            "example.com": "v=spf1 include:_spf.example.com ~all",
+            "test.com": "test-txt-record"
+        }
+    }
+
+
+@pytest.fixture(autouse=True)
+def reset_environment():
+    """Reset environment variables and state before each test."""
+    original_env = os.environ.copy()
+    yield
+    os.environ.clear()
+    os.environ.update(original_env)
+
+
+@pytest.fixture
+def capture_stdout(monkeypatch):
+    """Capture stdout for testing print statements."""
+    import io
+    import sys
+    
+    captured_output = io.StringIO()
+    monkeypatch.setattr(sys, 'stdout', captured_output)
+    yield captured_output
+    monkeypatch.undo()
+
+
+@pytest.fixture
+def mock_args():
+    """Create mock command line arguments."""
+    args = Mock()
+    args.interface = "127.0.0.1"
+    args.port = 53
+    args.tcp = False
+    args.ipv6 = False
+    args.file = None
+    args.fakeip = None
+    args.fakeipv6 = None
+    args.fakedomains = None
+    args.fakealias = None
+    args.fakens = None
+    args.fakemx = None
+    args.faketxt = None
+    args.fakecname = None
+    args.truedomains = None
+    args.nameservers = "8.8.8.8"
+    args.q = False
+    return args
\ No newline at end of file
diff --git a/tests/integration/__init__.py b/tests/integration/__init__.py
new file mode 100644
index 0000000..e69de29
diff --git a/tests/test_setup_validation.py b/tests/test_setup_validation.py
new file mode 100644
index 0000000..40b4d68
--- /dev/null
+++ b/tests/test_setup_validation.py
@@ -0,0 +1,97 @@
+import pytest
+import sys
+from pathlib import Path
+
+
+class TestSetupValidation:
+    """Validation tests to ensure the testing infrastructure is properly configured."""
+    
+    def test_pytest_is_available(self):
+        """Test that pytest is importable and available."""
+        import pytest
+        assert pytest.__version__
+        
+    def test_pytest_cov_is_available(self):
+        """Test that pytest-cov plugin is available."""
+        import pytest_cov
+        assert pytest_cov
+        
+    def test_pytest_mock_is_available(self):
+        """Test that pytest-mock plugin is available."""
+        import pytest_mock
+        assert pytest_mock
+        
+    def test_project_root_in_path(self):
+        """Test that the project root is in Python path."""
+        project_root = Path(__file__).parent.parent
+        assert str(project_root) in sys.path or str(project_root.absolute()) in sys.path
+        
+    def test_can_import_dnschef(self):
+        """Test that the main module can be imported."""
+        try:
+            import dnschef
+            assert dnschef.DNSCHEF_VERSION
+        except ImportError:
+            # Add parent directory to path and try again
+            sys.path.insert(0, str(Path(__file__).parent.parent))
+            import dnschef
+            assert dnschef.DNSCHEF_VERSION
+            
+    def test_fixtures_are_available(self, temp_dir, mock_config, mock_logger):
+        """Test that conftest fixtures are available and working."""
+        assert temp_dir.exists()
+        assert temp_dir.is_dir()
+        
+        assert mock_config.interface == "127.0.0.1"
+        assert mock_config.port == 53
+        
+        assert hasattr(mock_logger, 'info')
+        assert hasattr(mock_logger, 'error')
+        
+    def test_markers_are_defined(self, pytestconfig):
+        """Test that custom pytest markers are properly defined."""
+        markers = pytestconfig.getini('markers')
+        marker_names = [m.split(':')[0].strip() for m in markers]
+        assert 'unit' in marker_names
+        assert 'integration' in marker_names
+        assert 'slow' in marker_names
+        
+    @pytest.mark.unit
+    def test_unit_marker_works(self):
+        """Test that the unit test marker can be used."""
+        assert True
+        
+    @pytest.mark.integration
+    def test_integration_marker_works(self):
+        """Test that the integration test marker can be used."""
+        assert True
+        
+    @pytest.mark.slow
+    def test_slow_marker_works(self):
+        """Test that the slow test marker can be used."""
+        assert True
+        
+    def test_temp_file_fixture(self, temp_file):
+        """Test that the temp_file fixture works correctly."""
+        test_file = temp_file("test.txt", "Hello, World!")
+        assert test_file.exists()
+        assert test_file.read_text() == "Hello, World!"
+        
+    def test_mock_dns_query_fixture(self, mock_dns_query):
+        """Test that the mock DNS query fixture is properly configured."""
+        assert mock_dns_query.questions[0].qname == "example.com"
+        assert mock_dns_query.questions[0].qtype == 1
+        assert mock_dns_query.questions[0].qclass == 1
+        
+    def test_sample_dns_records_fixture(self, sample_dns_records):
+        """Test that the sample DNS records fixture provides expected data."""
+        assert "A" in sample_dns_records
+        assert "AAAA" in sample_dns_records
+        assert "MX" in sample_dns_records
+        assert sample_dns_records["A"]["example.com"] == "192.168.1.1"
+        
+    def test_coverage_is_enabled(self):
+        """Test that coverage tracking is properly configured."""
+        # This test will pass if pytest-cov is properly configured
+        # The actual coverage percentage will be checked by pytest-cov
+        assert True
\ No newline at end of file
diff --git a/tests/unit/__init__.py b/tests/unit/__init__.py
new file mode 100644
index 0000000..e69de29