diff --git a/docker/Dockerfile.test b/docker/Dockerfile.test
index 488a99cd6..770caf04d 100644
--- a/docker/Dockerfile.test
+++ b/docker/Dockerfile.test
@@ -10,6 +10,7 @@ RUN apt update \
   && apt install -y sudo opam
 
 RUN eval $(opam env) \
-  && LD_LIBRARY_PATH=/scilla/0/vcpkg_installed/x64-linux-dynamic/lib opam install reason.3.8.2 --yes
+  && LD_LIBRARY_PATH=/scilla/0/vcpkg_installed/x64-linux-dynamic/lib opam init --yes && \
+  LD_LIBRARY_PATH=/scilla/0/vcpkg_installed/x64-linux-dynamic/lib opam install reason.3.8.2 --yes
 
 RUN ./scripts/install_shellcheck_ubuntu.sh