diff --git a/dune-project b/dune-project
index 4f3cbf9d..7318d475 100644
--- a/dune-project
+++ b/dune-project
@@ -54,7 +54,8 @@
  (depopts atomic trace thread-local-storage lwt eio picos)
  (conflicts
   (trace
-   (< 0.12)))
+   (< 0.12))
+  (lwt (< 6)))
  (tags
   (instrumentation tracing opentelemetry datadog jaeger)))
 
@@ -85,9 +86,9 @@
   (cohttp-lwt-unix :with-test)
   (odoc :with-doc)
   (lwt
-   (>= "5.3"))
+   (>= "6"))
   (lwt_ppx
-   (>= "2.0"))
+   (>= "6"))
   (alcotest :with-test))
  (tags
   (instrumentation tracing opentelemetry datadog lwt)))
@@ -128,9 +129,9 @@
    (>= 0.2.3))
   ocurl
   (lwt
-   (>= "5.3"))
+   (>= "6"))
   (lwt_ppx
-   (>= "2.0"))
+   (>= "6"))
   (alcotest :with-test))
  (synopsis "Collector client for opentelemetry, using ezcurl-lwt"))
 
@@ -169,7 +170,7 @@
   ambient-context-lwt
   (odoc :with-doc)
   (lwt
-   (>= "5.3"))
+   (>= "6"))
   (cohttp
    (>= "6.0.0"))
   (cohttp-lwt
@@ -194,9 +195,9 @@
   ambient-context-lwt
   (odoc :with-doc)
   (lwt
-   (>= "5.3"))
+   (>= "6"))
   (lwt_ppx
-   (>= "2.0"))
+   (>= "6"))
   cohttp-lwt
   cohttp-lwt-unix
   (alcotest :with-test)
diff --git a/opentelemetry-client-cohttp-lwt.opam b/opentelemetry-client-cohttp-lwt.opam
index 71053b0b..72c62d13 100644
--- a/opentelemetry-client-cohttp-lwt.opam
+++ b/opentelemetry-client-cohttp-lwt.opam
@@ -20,8 +20,8 @@ depends: [
   "opentelemetry-lwt" {= version}
   "ambient-context-lwt"
   "odoc" {with-doc}
-  "lwt" {>= "5.3"}
-  "lwt_ppx" {>= "2.0"}
+  "lwt" {>= "6"}
+  "lwt_ppx" {>= "6"}
   "cohttp-lwt"
   "cohttp-lwt-unix"
   "alcotest" {with-test}
diff --git a/opentelemetry-client-ocurl-lwt.opam b/opentelemetry-client-ocurl-lwt.opam
index 1abeacf5..cbd5dfb3 100644
--- a/opentelemetry-client-ocurl-lwt.opam
+++ b/opentelemetry-client-ocurl-lwt.opam
@@ -20,8 +20,8 @@ depends: [
   "odoc" {with-doc}
   "ezcurl-lwt" {>= "0.2.3"}
   "ocurl"
-  "lwt" {>= "5.3"}
-  "lwt_ppx" {>= "2.0"}
+  "lwt" {>= "6"}
+  "lwt_ppx" {>= "6"}
   "alcotest" {with-test}
 ]
 build: [
diff --git a/opentelemetry-cohttp-lwt.opam b/opentelemetry-cohttp-lwt.opam
index 96de5e67..98976f34 100644
--- a/opentelemetry-cohttp-lwt.opam
+++ b/opentelemetry-cohttp-lwt.opam
@@ -18,7 +18,7 @@ depends: [
   "opentelemetry-lwt" {= version}
   "ambient-context-lwt"
   "odoc" {with-doc}
-  "lwt" {>= "5.3"}
+  "lwt" {>= "6"}
   "cohttp" {>= "6.0.0"}
   "cohttp-lwt" {>= "6.0.0"}
   "alcotest" {with-test}
diff --git a/opentelemetry-lwt.opam b/opentelemetry-lwt.opam
index ae34a990..23da900c 100644
--- a/opentelemetry-lwt.opam
+++ b/opentelemetry-lwt.opam
@@ -19,8 +19,8 @@ depends: [
   "ambient-context-lwt"
   "cohttp-lwt-unix" {with-test}
   "odoc" {with-doc}
-  "lwt" {>= "5.3"}
-  "lwt_ppx" {>= "2.0"}
+  "lwt" {>= "6"}
+  "lwt_ppx" {>= "6"}
   "alcotest" {with-test}
 ]
 build: [
diff --git a/opentelemetry.opam b/opentelemetry.opam
index cbe391fd..41c86be9 100644
--- a/opentelemetry.opam
+++ b/opentelemetry.opam
@@ -31,6 +31,7 @@ depends: [
 depopts: ["atomic" "trace" "thread-local-storage" "lwt" "eio" "picos"]
 conflicts: [
   "trace" {< "0.12"}
+  "lwt" {< "6"}
 ]
 build: [
   ["dune" "subst"] {dev}
diff --git a/src/client/lwt/notifier_lwt.ml b/src/client/lwt/notifier_lwt.ml
index 1e61a124..722ea3d1 100644
--- a/src/client/lwt/notifier_lwt.ml
+++ b/src/client/lwt/notifier_lwt.ml
@@ -5,7 +5,7 @@ module IO = Io_lwt
 type t = {
   notified: bool Atomic.t;
   cond: unit Lwt_condition.t;
-  notification: int;
+  notification: Lwt_unix.notification;
   lwt_tid: int;  (** thread ID where lwt runs *)
   deleted: bool Atomic.t;
 }