diff --git a/.github/workflows/pipeline.yml b/.github/workflows/pipeline.yml
index 3c5f8c0..a7bafd0 100644
--- a/.github/workflows/pipeline.yml
+++ b/.github/workflows/pipeline.yml
@@ -71,6 +71,6 @@ jobs:
 
       - name: Test with pytest
         run: |
-          conda run pip install .[testing]
+          conda run pip install . --group testing
           conda install -c conda-forge cadet>=5.0.3
           pytest tests --rootdir=tests -m "not slow and not local"
diff --git a/pyproject.toml b/pyproject.toml
index 9419c06..134ba1f 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -32,7 +32,7 @@ dependencies = [
     "filelock",
 ]
 
-[project.optional-dependencies]
+[dependency-groups]
 testing = [
     "pytest",
     "joblib"