diff --git a/.github/workflows/build.yml b/.github/workflows/build.yml
index 79e969ffc5..aedaf06faa 100644
--- a/.github/workflows/build.yml
+++ b/.github/workflows/build.yml
@@ -41,6 +41,7 @@ jobs:
       - name: Use OCaml ${{ matrix.ocaml-compiler }}
         uses: ocaml/setup-ocaml@v2
         with:
+          allow-prelease-opam: true
           ocaml-compiler: ${{ matrix.ocaml-compiler }}
           dune-cache: true