diff --git a/.github/workflows/ci.yaml b/.github/workflows/ci.yaml
index 495bcca..c48ce0e 100644
--- a/.github/workflows/ci.yaml
+++ b/.github/workflows/ci.yaml
@@ -23,4 +23,8 @@ jobs:
         python -m pip install --upgrade pip wheel
         python -m pip install tox==4.* tox-gh-actions==3.*
     - name: Run tox
-      run: tox
\ No newline at end of file
+      run: tox
+    - name: System test
+      env:
+        SC_GITHUB_TOKEN: "${{ secrets.GITHUB_TOKEN }}"
+      run: .test/system-test/system_test.sh
diff --git a/src/security_constraints/common.py b/src/security_constraints/common.py
index f41f17f..971a5e6 100644
--- a/src/security_constraints/common.py
+++ b/src/security_constraints/common.py
@@ -1,4 +1,6 @@
 """This module contains common definitions for use in any other module."""
+from __future__ import annotations
+
 import abc
 import argparse
 import dataclasses
@@ -17,15 +19,14 @@
     get_type_hints,
 )
 
-if sys.version_info >= (3, 11):
-    from typing import Self  # pragma: no cover (<py311)
-else:
-    from typing_extensions import Self  # pragma: no cover (>=py311)
-
-
 if TYPE_CHECKING:  # pragma: no cover
     from typing import TypedDict
 
+    if sys.version_info >= (3, 11):
+        from typing import Self  # pragma: no cover (<py311)
+    else:
+        from typing_extensions import Self  # pragma: no cover (>=py311)
+
     class _ConfigurationKwargs(TypedDict, total=False):
         ignore_ids: Set[str]
         min_severity: "SeverityLevel"
@@ -40,7 +41,7 @@ class SeverityLevel(str, enum.Enum):
     LOW = "LOW"
 
     @classmethod
-    def _missing_(cls: Type[Self], value: object) -> Optional[Self]:
+    def _missing_(cls, value: object) -> Optional[Self]:
         # Makes instantiation case-insensitive
         if isinstance(value, str):
             for member in cls:
@@ -48,7 +49,7 @@ def _missing_(cls: Type[Self], value: object) -> Optional[Self]:
                     return member
         return None
 
-    def get_higher_or_equal_severities(self: Self) -> Set[Self]:
+    def get_higher_or_equal_severities(self) -> Set[Self]:
         """Get a set containing this SeverityLevel and all higher ones."""
         return {
             type(self)(value)
@@ -110,7 +111,7 @@ class ArgumentNamespace(argparse.Namespace):
 
     def __setattr__(self, key: str, value: Any) -> None:
         # Makes it so that no attributes except those type hinted above can be set.
-        if key not in get_type_hints(self):
+        if key not in self.__annotations__: #get_type_hints(self):
             raise AttributeError(f"No attribute named '{key}'")
         super().__setattr__(key, value)
 
diff --git a/test/system_test/sc-conf.yaml b/test/system_test/sc-conf.yaml
new file mode 100644
index 0000000..0463a1a
--- /dev/null
+++ b/test/system_test/sc-conf.yaml
@@ -0,0 +1,2 @@
+ignore_ids:
+  - "GHSA-8r8j-xvfj-36f9"
diff --git a/test/system_test/system_test.sh b/test/system_test/system_test.sh
new file mode 100755
index 0000000..cab5eab
--- /dev/null
+++ b/test/system_test/system_test.sh
@@ -0,0 +1,23 @@
+#!/usr/bin/env bash
+
+echo "Preparing system test..."
+THIS_DIR="$(dirname "$0")"
+pushd "${THIS_DIR}" &> /dev/null || exit 1
+VENV=$(mktemp --directory)
+python -m venv "${VENV}"
+. "${VENV}/bin/activate"
+"${VENV}/bin/python3" -m pip install --quiet --upgrade pip
+"${VENV}/bin/python3" -m pip install --quiet --editable "$(git rev-parse --show-toplevel)" || exit 1
+OUTPUT_FILE=$(mktemp)
+
+echo "Executing system test..."
+security-constraints --config="sc-conf.yaml" --output="${OUTPUT_FILE}"  || exit 1
+
+echo "Verifying that ID from config was ignored..."
+test -z "$(grep --files-with-match "(ID: GHSA-8r8j-xvfj-3fff6f9)" "${OUTPUT_FILE}" )" || exit 1
+echo "Verifying that pip install works with the output file..."
+"${VENV}/bin/python3" -m pip install --quiet --dry-run ymlref --constraint="${OUTPUT_FILE}" || exit 1
+
+popd &> /dev/null || exit 1
+
+echo "System test passed!"