diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index fc6808dd4b75c63e79dca3abdfc59c80535c6c70..5746d2b7b0d8f8b4d54679b1a9c486703b2233d7 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -1,4 +1,4 @@
-image: ocaml/opam2
+image: ubuntu-16.04_ocaml-4.06.0
 
 stages:
   - build
@@ -10,6 +10,7 @@ test:
     - opam repo add opamorg "https://opam.ocaml.org/1.2.2"
     - opam repo add verimag-sync-repo "http://www-verimag.imag.fr/DIST-TOOLS/SYNCHRONE/opam-repository"
     - opam update -y
+    - opam switch 4.07.0
     - opam depext -y lustre-v6  lutin
     - opam install -y dune ocamlgraph lutin
     - make
diff --git a/lib/sasacore/dune-project b/lib/sasacore/dune-project
new file mode 100644
index 0000000000000000000000000000000000000000..f75713fb8c409db59b961e7905989483fb90578d
--- /dev/null
+++ b/lib/sasacore/dune-project
@@ -0,0 +1 @@
+(lang dune 1.2)
diff --git a/lib/sasalib/dune-project b/lib/sasalib/dune-project
new file mode 100644
index 0000000000000000000000000000000000000000..f75713fb8c409db59b961e7905989483fb90578d
--- /dev/null
+++ b/lib/sasalib/dune-project
@@ -0,0 +1 @@
+(lang dune 1.2)
diff --git a/src/dune-project b/src/dune-project
new file mode 100644
index 0000000000000000000000000000000000000000..f75713fb8c409db59b961e7905989483fb90578d
--- /dev/null
+++ b/src/dune-project
@@ -0,0 +1 @@
+(lang dune 1.2)