diff --git a/.github/workflows/main.yml b/.github/workflows/main.yml
index 30977e4..ec24eff 100644
--- a/.github/workflows/main.yml
+++ b/.github/workflows/main.yml
@@ -30,7 +30,7 @@ jobs:
           conda config --system --set channel_priority strict
           mamba create -y -n gffutils-env \
             python=${{ matrix.python-version }} \
-            --file requirements.txt
+            bedtools
 
           conda activate gffutils-env
           python setup.py clean sdist
@@ -43,9 +43,9 @@ jobs:
         run: |
           source "${HOME}/conda/etc/profile.d/conda.sh"
           source "${HOME}/conda/etc/profile.d/mamba.sh"
-          mamba install -y -n gffutils-env --file optional-requirements.txt pytest hypothesis
 
           conda activate gffutils-env
+          pip install pytest hypothesis biopython
           pytest -v --doctest-modules gffutils
           conda deactivate