diff --git a/caisar-ir.opam b/caisar-ir.opam
index 98ea1897d38bbf6e638bbdcdd3abc34390e4887b..a559ab51f6fb45f82b9d97fa7b52f404664d9ff4 100644
--- a/caisar-ir.opam
+++ b/caisar-ir.opam
@@ -14,7 +14,6 @@ depends: [
   "ocaml" {>= "4.13"}
   "dune" {>= "2.9" & >= "2.9.3"}
   "base" {>= "v0.14.0"}
-  "ocaml-protoc-plugin" {= "4.2.0"}
   "ocamlgraph" {>= "1.8.8"}
   "ppx_inline_test" {>= "0.12.0"}
   "ppx_deriving" {>= "4.4.1"}
diff --git a/caisar-onnx.opam b/caisar-onnx.opam
index cf26b6b30df85afe93d55379b97d05ddbffbaeb2..28b266031ec4dac75c0545840f03fee90dbe4956 100644
--- a/caisar-onnx.opam
+++ b/caisar-onnx.opam
@@ -16,6 +16,7 @@ depends: [
   "base" {>= "v0.14.0"}
   "stdio" {>= "v0.14.0"}
   "ocaml-protoc-plugin" {>= "4.2.0"}
+  "ocplib-endian" {>= "1.0"}
   "odoc" {with-doc}
 ]
 build: [
diff --git a/dune-project b/dune-project
index 948b6643b332729ee52372b22a7b1afc4bef7996..e035c42f682e617691e0cb45a5a582a57ee68b0d 100644
--- a/dune-project
+++ b/dune-project
@@ -45,6 +45,7 @@
    (base (>= v0.14.0))
    (stdio (>= v0.14.0))
    (ocaml-protoc-plugin (>= 4.2.0))
+   (ocplib-endian (>= 1.0))
   )
 )
 
@@ -55,7 +56,6 @@
    (ocaml (>= 4.13))
    (dune (>= 2.9.3))
    (base (>= v0.14.0))
-   (ocaml-protoc-plugin (= 4.2.0))
    (ocamlgraph (>= 1.8.8))
    (ppx_inline_test (>= 0.12.0))
    (ppx_deriving (>= 4.4.1))
diff --git a/lib/ir/dune b/lib/ir/dune
index 5b92d58d7c631fea187dbb2cfa94b6501f42ffd2..bacd51c99513e5922dadd6b3795781a43c3a2f92 100644
--- a/lib/ir/dune
+++ b/lib/ir/dune
@@ -9,7 +9,7 @@
    ppx_deriving.iter
    ppx_deriving.fold))
  (inline_tests)
- (libraries base ocplib-endian ocamlgraph stdio))
+ (libraries base ocamlgraph stdio))
 
 (env
  (dev
diff --git a/lib/onnx/dune b/lib/onnx/dune
index ae47764e9d1ef1fc911e72084072b4ab02690fd4..9d5fdba2284917e0bacf73a6933596bce2c14b5b 100644
--- a/lib/onnx/dune
+++ b/lib/onnx/dune
@@ -1,7 +1,7 @@
 (library
  (name onnx)
  (public_name caisar-onnx)
- (libraries base stdio ocaml-protoc-plugin caisar-ir)
+ (libraries base stdio ocaml-protoc-plugin ocplib-endian caisar-ir)
  (synopsis "ONNX parser for CAISAR"))
 
 (rule