diff --git a/.github/workflows/set-up-environment.yml b/.github/workflows/set-up-environment.yml
index 39bd80e..18dc6ae 100644
--- a/.github/workflows/set-up-environment.yml
+++ b/.github/workflows/set-up-environment.yml
@@ -23,6 +23,7 @@ jobs:
         eval $(opam env)
         cp $(which alt-ergo) $(which alt-ergo)-2.4.2
         opam install alt-ergo.2.5.3
+        eval $(opam env)
         opam install eprover.2.6
         # it's possible to install z3 as follows
         # opam install z3.4.11.2