diff --git a/pyproject.toml b/pyproject.toml
index 4b729791e..4e09fe997 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -11,6 +11,16 @@ requires-python = ">=3.10,<3.13"
 dynamic = ["version"]
 dependencies = ["pybind11", "transformers", "zmq", "xxhash", "fastapi", "psutil", "protobuf", "uvicorn", "aiohttp"]
 
+[project.optional-dependencies]
+dev = ["pytest>=7.0.0", "pytest-cov>=4.0.0"]
+
+[tool.pytest.ini_options]
+testpaths = ["tests"]
+python_files = ["test_*.py"]
+python_classes = ["Test*"]
+python_functions = ["test_*"]
+addopts = "-v --tb=short"
+
 [project.urls]
 Homepage = "https://github.com/ROCm/ATOM"
 Repository = "https://github.com/ROCm/ATOM"
diff --git a/tests/__init__.py b/tests/__init__.py
new file mode 100644
index 000000000..0538f32cb
--- /dev/null
+++ b/tests/__init__.py
@@ -0,0 +1,2 @@
+# ATOM Unit Tests
+
diff --git a/tests/test_config.py b/tests/test_config.py
new file mode 100644
index 000000000..91c745de1
--- /dev/null
+++ b/tests/test_config.py
@@ -0,0 +1,53 @@
+"""Unit tests for config classes."""
+
+import pytest
+from atom.config import CompilationConfig, CompilationLevel, CUDAGraphMode
+
+
+class TestCUDAGraphMode:
+
+    def test_mode_values(self):
+        assert CUDAGraphMode.NONE.value == 0
+        assert CUDAGraphMode.PIECEWISE.value == 1
+        assert CUDAGraphMode.FULL.value == 2
+        assert CUDAGraphMode.FULL_DECODE_ONLY.value == (2, 0)
+        assert CUDAGraphMode.FULL_AND_PIECEWISE.value == (2, 1)
+
+    def test_separate_routine(self):
+        assert CUDAGraphMode.NONE.separate_routine() is False
+        assert CUDAGraphMode.FULL_DECODE_ONLY.separate_routine() is True
+
+    def test_decode_and_mixed_mode(self):
+        assert CUDAGraphMode.FULL_DECODE_ONLY.decode_mode() == CUDAGraphMode.FULL
+        assert CUDAGraphMode.FULL_DECODE_ONLY.mixed_mode() == CUDAGraphMode.NONE
+        assert CUDAGraphMode.FULL_AND_PIECEWISE.mixed_mode() == CUDAGraphMode.PIECEWISE
+
+    def test_has_full_cudagraphs(self):
+        assert CUDAGraphMode.NONE.has_full_cudagraphs() is False
+        assert CUDAGraphMode.FULL.has_full_cudagraphs() is True
+
+    def test_requires_piecewise_compilation(self):
+        assert CUDAGraphMode.PIECEWISE.requires_piecewise_compilation() is True
+        assert CUDAGraphMode.FULL.requires_piecewise_compilation() is False
+
+
+class TestCompilationConfig:
+
+    def test_default_values(self):
+        config = CompilationConfig()
+        assert config.level == 0
+        assert config.use_cudagraph is True
+        assert config.cuda_graph_sizes == [512]
+
+    def test_invalid_level_raises_error(self):
+        with pytest.raises(ValueError, match="level must in 0-3"):
+            CompilationConfig(level=5)
+
+    def test_compute_hash_consistency(self):
+        config = CompilationConfig(level=1)
+        assert config.compute_hash() == config.compute_hash()
+
+    def test_set_splitting_ops_for_v1(self):
+        config = CompilationConfig(level=CompilationLevel.PIECEWISE)
+        config.set_splitting_ops_for_v1()
+        assert "aiter.unified_attention_with_output" in config.splitting_ops
diff --git a/tests/test_sampling_params.py b/tests/test_sampling_params.py
new file mode 100644
index 000000000..081edca7b
--- /dev/null
+++ b/tests/test_sampling_params.py
@@ -0,0 +1,31 @@
+"""Unit tests for SamplingParams class."""
+
+import pytest
+from atom.sampling_params import SamplingParams
+
+
+class TestSamplingParams:
+
+    def test_default_values(self):
+        params = SamplingParams()
+        assert params.temperature == 1.0
+        assert params.max_tokens == 64
+        assert params.ignore_eos is False
+        assert params.stop_strings is None
+
+    def test_custom_values(self):
+        params = SamplingParams(
+            temperature=0.5,
+            max_tokens=256,
+            ignore_eos=True,
+            stop_strings=["<|end|>", "STOP"]
+        )
+        assert params.temperature == 0.5
+        assert params.max_tokens == 256
+        assert params.ignore_eos is True
+        assert params.stop_strings == ["<|end|>", "STOP"]
+
+    def test_equality(self):
+        params1 = SamplingParams(temperature=0.8, max_tokens=100)
+        params2 = SamplingParams(temperature=0.8, max_tokens=100)
+        assert params1 == params2
diff --git a/tests/test_simple.py b/tests/test_simple.py
new file mode 100644
index 000000000..114cbcb23
--- /dev/null
+++ b/tests/test_simple.py
@@ -0,0 +1,8 @@
+"""Simple sanity test."""
+
+
+def test_import():
+    """Test that core modules can be imported."""
+    from atom.sampling_params import SamplingParams
+    assert SamplingParams is not None
+