diff --git a/dune-project b/dune-project
index 5c32ef3df..eb94007c0 100644
--- a/dune-project
+++ b/dune-project
@@ -1,12 +1,10 @@
-(lang dune 2.7)
+(lang dune 3.17)
 
 (name lwt)
 
 (generate_opam_files true)
 
-(maintainers
- "Raphaël Proust <code@bnwr.net>"
- "Anton Bachin <antonbachin@yahoo.com>")
+(maintainers "Raphaël Proust <code@bnwr.net>" "Anton Bachin <antonbachin@yahoo.com>")
 (authors "Jérôme Vouillon" "Jérémie Dimino")
 (license MIT)
 (source (github ocsigen/lwt))
@@ -16,9 +14,7 @@
  (name lwt_retry)
  (synopsis "Utilities for retrying Lwt computations")
  (authors "Shon Feder")
- (maintainers
-   "Raphaël Proust <code@bnwr.net>"
-   "Shon Feder <shon.feder@gmail.com>")
+ (maintainers "Raphaël Proust <code@bnwr.net>" "Shon Feder <shon.feder@gmail.com>")
  (depends
   (ocaml (>= 4.08))
   (lwt (>= 5.3.0))
diff --git a/lwt.opam b/lwt.opam
index 93a3ed64c..88872e8dd 100644
--- a/lwt.opam
+++ b/lwt.opam
@@ -20,7 +20,7 @@ homepage: "https://github.com/ocsigen/lwt"
 doc: "https://ocsigen.org/lwt"
 bug-reports: "https://github.com/ocsigen/lwt/issues"
 depends: [
-  "dune" {>= "2.7"}
+  "dune" {>= "3.17"}
   "ocaml" {>= "4.08"}
   "cppo" {build & >= "1.1.0"}
   "ocamlfind" {dev & >= "1.7.3-1"}
diff --git a/lwt_ppx.opam b/lwt_ppx.opam
index 57b2c210f..eca3338f7 100644
--- a/lwt_ppx.opam
+++ b/lwt_ppx.opam
@@ -11,7 +11,7 @@ homepage: "https://github.com/ocsigen/lwt"
 doc: "https://ocsigen.org/lwt"
 bug-reports: "https://github.com/ocsigen/lwt/issues"
 depends: [
-  "dune" {>= "2.7"}
+  "dune" {>= "3.17"}
   "ocaml" {>= "4.08"}
   "ppxlib" {>= "0.16.0"}
   "ppx_let" {with-test}
diff --git a/lwt_react.opam b/lwt_react.opam
index c506050bd..e2ef69746 100644
--- a/lwt_react.opam
+++ b/lwt_react.opam
@@ -10,7 +10,7 @@ homepage: "https://github.com/ocsigen/lwt"
 doc: "https://ocsigen.org/lwt"
 bug-reports: "https://github.com/ocsigen/lwt/issues"
 depends: [
-  "dune" {>= "2.7"}
+  "dune" {>= "3.17"}
   "ocaml" {>= "4.08"}
   "cppo" {build & >= "1.1.0"}
   "lwt" {>= "3.0.0"}
diff --git a/lwt_retry.opam b/lwt_retry.opam
index 879deec73..704d0659c 100644
--- a/lwt_retry.opam
+++ b/lwt_retry.opam
@@ -10,7 +10,7 @@ homepage: "https://github.com/ocsigen/lwt"
 doc: "https://ocsigen.org/lwt"
 bug-reports: "https://github.com/ocsigen/lwt/issues"
 depends: [
-  "dune" {>= "2.7"}
+  "dune" {>= "3.17"}
   "ocaml" {>= "4.08"}
   "lwt" {>= "5.3.0"}
   "bisect_ppx" {with-test}
diff --git a/src/unix/lwt_io.ml b/src/unix/lwt_io.ml
index 9a24aa02a..be08df3cb 100644
--- a/src/unix/lwt_io.ml
+++ b/src/unix/lwt_io.ml
@@ -73,7 +73,7 @@ and 'mode channel = {
   channel : 'mode _channel;
   (* The real channel *)
 
-  mutable queued : unit Lwt.u Lwt_sequence.t;
+  mutable queued : unit Lwt.u Lwt_sequence.t [@ocaml.warning "-69"];
   (* Queued operations *)
 }