diff --git a/lwt.opam b/lwt.opam
index f1efd23e87..db1d81fdc9 100644
--- a/lwt.opam
+++ b/lwt.opam
@@ -2,7 +2,7 @@ opam-version: "2.0"
 
 synopsis: "Promises and event-driven I/O"
 
-version: "dev"
+version: "4.3.1"
 license: "MIT"
 homepage: "https://github.com/ocsigen/lwt"
 doc: "https://ocsigen.org/lwt/manual/"
diff --git a/src/core/dune b/src/core/dune
index 6253235bdf..30d0e9eedc 100644
--- a/src/core/dune
+++ b/src/core/dune
@@ -2,6 +2,5 @@
  (public_name lwt)
  (synopsis "Monadic promises and concurrent I/O")
  (wrapped false)
- (preprocess (pps bisect_ppx --conditional))
  (libraries bytes result seq)
  (flags (:standard -w +A-29)))
diff --git a/src/react/dune b/src/react/dune
index 318cb3c757..7d1680b6c0 100644
--- a/src/react/dune
+++ b/src/react/dune
@@ -10,5 +10,4 @@
  (synopsis "Reactive programming helpers for Lwt")
  (wrapped false)
  (libraries lwt react)
- (preprocess (pps bisect_ppx --conditional))
  (flags (:standard -w +A)))
diff --git a/src/unix/dune b/src/unix/dune
index f876bb701b..3cec28da4b 100644
--- a/src/unix/dune
+++ b/src/unix/dune
@@ -33,7 +33,6 @@
  (optional)
  (wrapped false)
  (libraries bigarray lwt mmap ocplib-endian.bigstring threads unix)
- (preprocess (pps bisect_ppx --conditional))
  (flags (:standard -w +A-29))
  (c_names
   lwt_unix_stubs