diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index 5da718c5b0c09aee7284556711f1be27c0d09e2f..3ad750a4ba3df8886e846e08cd3846cb81981342 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -5,6 +5,7 @@ stages:
 
 variables:
   CPU_CORES: "10"
+  OCAML: "ocaml-variants.4.14.0+options ocaml-option-flambda"
 
 .template: &template
   stage: build