diff --git a/.github/workflows/codeql-analysis.yml b/.github/workflows/codeql-analysis.yml
index 43e0aef9e..69b63ee29 100644
--- a/.github/workflows/codeql-analysis.yml
+++ b/.github/workflows/codeql-analysis.yml
@@ -64,6 +64,8 @@ jobs:
         sudo apt-get update
         sudo apt-get install -y pkg-config build-essential
         sudo apt-get install -y libssl-dev libacl1-dev libxxhash-dev liblz4-dev libzstd-dev
+        python3 -m venv ../borg-env
+        source ../borg-env/bin/activate
         pip3 install -r requirements.d/development.txt
         pip3 install -e .
 
diff --git a/pyproject.toml b/pyproject.toml
new file mode 100644
index 000000000..cda60db81
--- /dev/null
+++ b/pyproject.toml
@@ -0,0 +1,3 @@
+[build-system]
+requires = ["setuptools", "pkgconfig", "Cython!=0.27"]
+build-backend = "setuptools.build_meta"
diff --git a/setup.py b/setup.py
index bc1d000c1..8b6a42460 100644
--- a/setup.py
+++ b/setup.py
@@ -19,6 +19,7 @@ try:
 except ImportError:
     cythonize = None
 
+sys.path += [os.path.dirname(__file__)]
 import setup_checksums
 import setup_compress
 import setup_crypto