diff --git a/package/pyproject.toml b/package/pyproject.toml
index ea50b37d..31e53907 100644
--- a/package/pyproject.toml
+++ b/package/pyproject.toml
@@ -13,6 +13,20 @@ dependencies = [
     "pydicom~=3.0.1",
     "dicom2nifti~=2.6.2",
 ]
+[project.optional-dependencies]
+backend = [
+    "fastapi",
+    "uvicorn",
+    "httpx"
+]
+
+pdf = [
+    "weasyprint"
+]
+
+dev = [
+    "pytest"
+]
 
 [build-system]
 requires = ["setuptools", "wheel"]
diff --git a/package/src/pyaslreport/tests/test_package.py b/package/src/pyaslreport/tests/test_package.py
index fda43d33..9eccc383 100644
--- a/package/src/pyaslreport/tests/test_package.py
+++ b/package/src/pyaslreport/tests/test_package.py
@@ -1,9 +1,18 @@
 import pytest
 from unittest.mock import patch, MagicMock
-from .main import get_bids_metadata
+from pyaslreport.main import get_bids_metadata
 
-# filepath: /home/ibrahim/MyPc/Projects/GSoC/ASL-Parameter-Generator/package/src/pyaslreport/test_main.py
+# Test missing keys safely
+def test_missing_key_returns_none():
+    data = {"dicom_dir": "/fake/path", "modality": None}
+    with patch("pyaslreport.main.get_dicom_header", return_value=None), \
+         patch("pyaslreport.main.get_sequence", return_value=None):
+        import pytest
+        with pytest.raises(ValueError) as exc:
+            get_bids_metadata(data)
+        assert "No matching sequence found" in str(exc.value)
 
+# Test: normal successful run
 def test_get_bids_metadata_success():
     data = {"modality": "asl", "dicom_dir": "/fake/dir"}
     fake_header = MagicMock()
@@ -15,11 +24,13 @@ def test_get_bids_metadata_success():
         assert result == ("meta", "context")
         fake_sequence.extract_bids_metadata.assert_called_once()
 
+# Test: no dicom_dir raises TypeError
 def test_get_bids_metadata_no_dicom_dir():
     data = {"modality": "asl"}
     with pytest.raises(TypeError):
         get_bids_metadata(data)
 
+# Test: no sequence raises ValueError
 def test_get_bids_metadata_no_sequence():
     data = {"modality": "asl", "dicom_dir": "/fake/dir"}
     fake_header = MagicMock()
@@ -29,6 +40,7 @@ def test_get_bids_metadata_no_sequence():
             get_bids_metadata(data)
         assert "No matching sequence found" in str(exc.value)
 
+# Test: invalid modality raises ValueError
 def test_get_bids_metadata_invalid_modality():
     data = {"modality": None, "dicom_dir": "/fake/dir"}
     fake_header = MagicMock()
diff --git a/pytest.ini b/pytest.ini
new file mode 100644
index 00000000..31645374
--- /dev/null
+++ b/pytest.ini
@@ -0,0 +1,3 @@
+[pytest] 
+testpaths = package/src/pyaslreport/tests 
+addopts = -m "not backend"