diff --git a/README.md b/README.md
new file mode 100644
index 0000000..f1980ee
--- /dev/null
+++ b/README.md
@@ -0,0 +1,2 @@
+[Lwt](https://ocsigen.org/lwt/) is a lightweight thread library for Objective
+Caml.  This library is part of the [Ocsigen project](https://ocsigen.org/).
diff --git a/ocaml-lwt.spec b/ocaml-lwt.spec
index 5459031..bc2b37a 100644
--- a/ocaml-lwt.spec
+++ b/ocaml-lwt.spec
@@ -1,6 +1,6 @@
 Name:           ocaml-lwt
 Version:        5.4.2
-Release:        3%{?dist}
+Release:        4%{?dist}
 Summary:        OCaml lightweight thread library
 
 # The openssl linking exception is granted.
@@ -29,7 +29,7 @@ BuildRequires:  ocaml-luv-devel
 BuildRequires:  ocaml-react-devel
 
 # lwt_ppx dependencies.
-BuildRequires:  ocaml-ppxlib >= 0.16.0
+BuildRequires:  ocaml-ppxlib-devel >= 0.16.0
 
 BuildRequires:  glib2-devel
 BuildRequires:  libev-devel
@@ -122,7 +122,7 @@ sed 's,test_mcast "mcast-nojoin-noloop" false false;,(*test_mcast "mcast-nojoin-
 # Enable libev and pthread.
 dune exec src/unix/config/discover.exe -- --save \
      --use-libev true --use-pthread true
-dune build --profile=release --verbose
+dune build %{?_smp_mflags} --profile=release --verbose
 
 # Relink the stublib with RPM_LD_FLAGS
 cd _build/default/src/unix
@@ -257,6 +257,9 @@ dune runtest --profile=release
 
 
 %changelog
+* Mon Dec 27 2021 Jerry James <loganjerry@gmail.com> - 5.4.2-4
+- Rebuild for ocaml-ppxlib 0.24.0
+
 * Tue Nov 30 2021 Jerry James <loganjerry@gmail.com> - 5.4.2-3
 - Rebuild for ocaml-sexplib0 0.15.0