diff --git a/pyproject.toml b/pyproject.toml
index 8ad05c1..6083f2a 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -13,4 +13,9 @@ dependencies = ["tabulate"]
 requires = ["hatchling"]
 build-backend = "hatchling.build"
 [tool.hatch.build.targets.wheel]
-packages = ["matrixmania"]
\ No newline at end of file
+packages = ["matrixmania"]
+
+[tool.pytest.ini_options]
+pythonpath = [
+    "."
+]
diff --git a/tests/test_matmul.py b/tests/test_matmul.py
new file mode 100644
index 0000000..d29fc3b
--- /dev/null
+++ b/tests/test_matmul.py
@@ -0,0 +1,14 @@
+from matrixmania.compute import matmul, transpose
+import pytest
+
+def test_matmul_basic():
+    a = [[1, 2], [3, 4]]
+    b = [[2, 0], [1, 2]]
+    expected = [[4, 4], [10, 8]]
+    assert matmul(a, b) == expected
+
+def test_matmul_invalid_dimensions():
+    a = [[1, 2, 3]]
+    b = [[1, 2], [3, 4]]
+    with pytest.raises(ValueError):
+        matmul(a, b)
diff --git a/tests/test_rot.py b/tests/test_rot.py
new file mode 100644
index 0000000..a894443
--- /dev/null
+++ b/tests/test_rot.py
@@ -0,0 +1,20 @@
+from matrixmania.compute import rot_2D
+import math
+
+def test_rot_2D_identity():
+    """Rotation by 0 radians should return identity matrix"""
+    result = rot_2D(0)
+    expected = [[1, 0], [0, 1]]
+    assert all(abs(result[i][j] - expected[i][j]) < 1e-9 for i in range(2) for j in range(2))
+
+def test_rot_2D_90_degrees():
+    """Rotation by 90° (pi/2 radians)"""
+    result = rot_2D(math.pi / 2)
+    expected = [[0, -1], [1, 0]]
+    assert all(abs(result[i][j] - expected[i][j]) < 1e-9 for i in range(2) for j in range(2))
+
+def test_rot_2D_180_degrees():
+    """Rotation by 180° (pi radians)"""
+    result = rot_2D(math.pi)
+    expected = [[-1, 0], [0, -1]]
+    assert all(abs(result[i][j] - expected[i][j]) < 1e-9 for i in range(2) for j in range(2))