diff --git a/Makefile b/Makefile
index dfb7f910d..634b4fe12 100644
--- a/Makefile
+++ b/Makefile
@@ -234,10 +234,10 @@ archi: $(EXTRA_DIR)/ocamldot/ocamldot
 	echo "}" >> archi.dot
 	dot -Tpdf archi.dot > archi.pdf
 
-lock:
+lock: clean lib
 	opam lock ./alt-ergo-lib.opam -w
 	# Remove OCaml compiler constraints
-	sed -i '/\"ocaml/d' ./alt-ergo-lib.opam.locked
+	sed -i '/"ocaml"\|"ocaml-base-compiler"\|"ocaml-system"\|"ocaml-config"/d' ./alt-ergo-lib.opam.locked
 
 dev-switch:
 	opam switch create -y . --deps-only --ignore-constraints-on alt-ergo-lib,alt-ergo-parsers
diff --git a/alt-ergo-lib.opam.locked b/alt-ergo-lib.opam.locked
index a20d5205d..f6a052ac8 100644
--- a/alt-ergo-lib.opam.locked
+++ b/alt-ergo-lib.opam.locked
@@ -43,6 +43,9 @@ depends: [
   "menhirLib" {= "20230608"}
   "menhirSdk" {= "20230608"}
   "num" {= "1.4"}
+  "ocaml-compiler-libs" {= "v0.12.4"}
+  "ocamlbuild" {= "0.14.2"}
+  "ocamlfind" {= "1.9.6"}
   "ocplib-endian" {= "1.2"}
   "ocplib-simplex" {= "0.5"}
   "pp_loc" {= "2.1.0"}