diff --git a/CHANGES.md b/CHANGES.md
index b2639b70..4a9a3b08 100644
--- a/CHANGES.md
+++ b/CHANGES.md
@@ -1,5 +1,5 @@
-v4.0.0
-------
+v4.0.0 2019-03-25
+-----------------
 
 - Sexplib is now an optional library for the base `Cstruct` module.
   A new `Cstruct_sexp` module has been introduced with the serialiser
@@ -16,6 +16,9 @@ v4.0.0
   packages to ensure that they pick up this version of the library.
   (fixes #222, @avsm)
 
+- JavaScript stubs are now installed using the jsoo mechanism
+  rather than a manual specification (#241 @jonludlam)
+
 - Use computed versions in opam files to ensure that dependent
   opam packages such as cstruct-async get the same base version
   of cstruct to avoid mismatches. (@avsm)
diff --git a/README.md b/README.md
index 1ce39d80..ae57cdb4 100644
--- a/README.md
+++ b/README.md
@@ -12,6 +12,8 @@ This repository provides several packages that can be installed via the
 [OPAM](https://opam.ocaml.org) package manager:
 
 - `cstruct`: the core Cstruct library
+- `cstruct-sexp`: serialisers into s-expression format of Cstructs
+- `cstruct-unix`: provide Unix variations of the read/write functions using file descriptors
 - `cstruct-async`: provide [Async](https://github.com/janestreet/async) Pipe and Bigstring support
 - `cstruct-lwt`: provide [Lwt](https://ocsigen.org/lwt) variants of read/write functions
 - `ppx_cstruct`: a [PPX](https://caml.inria.fr/pub/docs/manual-ocaml/extn.html#sec248) syntax extension (see below)
@@ -20,7 +22,7 @@ The libraries depend on OCaml version 4.02.3 and later, since it provides a
 [ppx](http://whitequark.org/blog/2014/04/16/a-guide-to-extension-points-in-ocaml/)
 extension point. The old
 [camlp4](http://caml.inria.fr/pub/docs/manual-camlp4/manual002.html)
-syntax extension is nolonger available; the last version which contained it
+syntax extension is nolonger available; the last cstruct release which contained it
 was v1.9.0.
 
 ### Local development
@@ -192,6 +194,10 @@ type foo64 =
 And `sexp_of_foo64` and `foo64_of_sexp` functions will also be available.
 The representation of the Sexp is the string representation of the enum.
 
+If you do use the sexp decorator, then you will also need to add
+`sexplib` to the dependency list for your package (both in the
+`dune` file and the `opam` file).
+
 Please see the `ppx_test/` directory for more in-depth examples.
 
 [![Build Status](https://travis-ci.org/mirage/ocaml-cstruct.svg)](https://travis-ci.org/mirage/ocaml-cstruct)