diff --git a/CONTRIBUTING.md b/CONTRIBUTING.md
index 6da47f0536f813c1b7ac766bbe335edf019762e0..453e89fedd6b646b1b0fd93ad24269beec19113e 100644
--- a/CONTRIBUTING.md
+++ b/CONTRIBUTING.md
@@ -5,7 +5,7 @@
 ```bash
 git clone ssh://git@gitlab.cern.ch:7999/lhcb-dpa/analysis-productions/apd.git
 cd apd
-mamba create -c conda-forge --name apd-dev requests requests-kerberos beautifulsoup4 click click-log ipython black pre-commit pytest
+mamba create -c conda-forge --name apd-dev requests requests-kerberos beautifulsoup4 click click-log ipython black pre-commit pytest responses
 conda activate apd-dev
 pip install -e .[testing]
 pre-commit install