diff --git a/.drone.yml b/.drone.yml
index baf3011..6a0bcc9 100644
--- a/.drone.yml
+++ b/.drone.yml
@@ -7,4 +7,6 @@ steps:
     commands:
       - sudo chown -R opam .
       - git -C /home/opam/opam-repository pull origin && opam update
-      - opam depext -i -t .
+      - opam pin add -n .
+      - opam --yes depext cert_service
+      - opam install -t -y cert_service