diff --git a/compiler/tests-ocaml/lib-effects/assume_no_perform.ml b/compiler/tests-ocaml/lib-effects/assume_no_perform.ml
index 5808e584c5..61cada4703 100644
--- a/compiler/tests-ocaml/lib-effects/assume_no_perform.ml
+++ b/compiler/tests-ocaml/lib-effects/assume_no_perform.ml
@@ -136,7 +136,7 @@ let () =
 
       (* The code below should be called in direct style despite the installed
          effect handler *)
-      Jsoo_runtime.Effect.assume_no_perform (fun () ->
+      Js_of_ocaml.Effect_js.assume_no_perform (fun () ->
           let m, sd = benchmark iter_fun 5 in
           let () = printf "Iter: mean = %f, sd = %f\n%!" m sd in
 
diff --git a/compiler/tests-ocaml/lib-effects/assume_no_perform_nested_handler.ml b/compiler/tests-ocaml/lib-effects/assume_no_perform_nested_handler.ml
index 25f152ee82..5d8ca5f52b 100644
--- a/compiler/tests-ocaml/lib-effects/assume_no_perform_nested_handler.ml
+++ b/compiler/tests-ocaml/lib-effects/assume_no_perform_nested_handler.ml
@@ -7,7 +7,7 @@ type _ Effect.t += Dummy : unit t
 let () =
   try_with
     (fun () ->
-      Jsoo_runtime.Effect.assume_no_perform (fun () ->
+      Js_of_ocaml.Effect_js.assume_no_perform (fun () ->
         try_with
           (fun () -> ())
           ()
diff --git a/compiler/tests-ocaml/lib-effects/assume_no_perform_unhandled.ml b/compiler/tests-ocaml/lib-effects/assume_no_perform_unhandled.ml
index a6ff920bdf..a0f52daf88 100644
--- a/compiler/tests-ocaml/lib-effects/assume_no_perform_unhandled.ml
+++ b/compiler/tests-ocaml/lib-effects/assume_no_perform_unhandled.ml
@@ -7,7 +7,7 @@ type _ Effect.t += Dummy : unit t
 let must_raise () =
   try_with
     (fun () ->
-      Jsoo_runtime.Effect.assume_no_perform (fun () ->
+      Js_of_ocaml.Effect_js.assume_no_perform (fun () ->
         (* Should raise [Effect.Unhandled] despite the installed handler *)
         perform Dummy
       )
diff --git a/lib/js_of_ocaml/dune b/lib/js_of_ocaml/dune
index 9dc2c3cfe1..df22bcb59a 100644
--- a/lib/js_of_ocaml/dune
+++ b/lib/js_of_ocaml/dune
@@ -1,8 +1,7 @@
 (library
  (name js_of_ocaml)
  (public_name js_of_ocaml)
- (libraries
-  (re_export js_of_ocaml-compiler.runtime))
+ (libraries js_of_ocaml-compiler.runtime)
  (foreign_stubs
   (language c)
   (names js_of_ocaml_stubs))
diff --git a/lib/js_of_ocaml/effect_js.ml b/lib/js_of_ocaml/effect_js.ml
new file mode 100644
index 0000000000..1401eaa015
--- /dev/null
+++ b/lib/js_of_ocaml/effect_js.ml
@@ -0,0 +1,20 @@
+(* Js_of_ocaml library
+ * http://www.ocsigen.org/js_of_ocaml/
+ * Copyright (C) 2024 Olivier Nicole
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License as published by
+ * the Free Software Foundation, with linking exception;
+ * either version 2.1 of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ *)
+
+external assume_no_perform : (unit -> 'a) -> 'a = "caml_assume_no_perform"
diff --git a/lib/js_of_ocaml/effect_js.mli b/lib/js_of_ocaml/effect_js.mli
new file mode 100644
index 0000000000..0ab148da25
--- /dev/null
+++ b/lib/js_of_ocaml/effect_js.mli
@@ -0,0 +1,31 @@
+(* Js_of_ocaml library
+ * http://www.ocsigen.org/js_of_ocaml/
+ * Copyright (C) 2024 Olivier Nicole
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License as published by
+ * the Free Software Foundation, with linking exception;
+ * either version 2.1 of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ *)
+
+(** Javascript-specific effect functions. *)
+
+external assume_no_perform : (unit -> 'a) -> 'a = "caml_assume_no_perform"
+(** Passing a function [f] as argument of `assume_no_perform` guarantees that,
+    when compiling with `--effects=double-translation`, the direct-style
+    version of [f] is called, which is faster than the CPS version. As a
+    consequence, performing an effect in a transitive callee of [f] will raise
+    `Effect.Unhandled`, regardless of any effect handlers installed before the
+    call to `assume_no_perform`, unless a new effect handler was installed in
+    the meantime.
+
+    This behaviour is the same when double translation is disabled. *)
diff --git a/lib/js_of_ocaml/js_of_ocaml.ml b/lib/js_of_ocaml/js_of_ocaml.ml
index dfd7799a2c..a0cdd5f30e 100644
--- a/lib/js_of_ocaml/js_of_ocaml.ml
+++ b/lib/js_of_ocaml/js_of_ocaml.ml
@@ -22,6 +22,7 @@ module Dom = Dom
 module Dom_events = Dom_events
 module Dom_html = Dom_html
 module Dom_svg = Dom_svg
+module Effect_js = Effect_js
 module EventSource = EventSource
 module File = File
 module Firebug = Firebug