diff --git a/README.md b/README.md
index 45b5be5..819b0bd 100644
--- a/README.md
+++ b/README.md
@@ -1,2 +1,4 @@
 # ocaml-lwt
 
+OCaml promises and concurrent I/O.
+
diff --git a/ocaml-lwt.spec b/ocaml-lwt.spec
new file mode 100644
index 0000000..190916e
--- /dev/null
+++ b/ocaml-lwt.spec
@@ -0,0 +1,91 @@
+%define ocamlpck  lwt
+
+Name:          ocaml-lwt
+Version:       5.5.0
+Release:       1mamba
+Summary:       OCaml promises and concurrent I/O
+Group:         System/Libraries/OCaml
+Vendor:        openmamba
+Distribution:  openmamba
+Packager:      Silvan Calarco <silvan.calarco@mambasoft.it>
+URL:           https://ocsigen.org/lwt
+Source:        https://github.com/ocsigen/lwt.git/%{version}/lwt-%{version}.tar.bz2
+License:       MIT
+## AUTOBUILDREQ-BEGIN
+BuildRequires: glibc-devel
+BuildRequires: ocaml
+BuildRequires: ocaml-compiler-libs
+BuildRequires: ocaml-compiler-libs-repackaged
+BuildRequires: ocaml-ctypes-devel
+BuildRequires: ocaml-integers
+BuildRequires: ocaml-luv-devel
+BuildRequires: ocaml-mmap-devel
+BuildRequires: ocaml-ocplib-endian-devel
+BuildRequires: ocaml-ppxlib-devel
+BuildRequires: ocaml-react-devel
+BuildRequires: ocaml-result
+BuildRequires: ocaml-runtime
+BuildRequires: ocaml-seq-devel
+BuildRequires: ocaml-sexplib0-devel
+## AUTOBUILDREQ-END
+BuildRequires: ocaml
+BuildRequires: ocaml-camlp4-devel
+BuildRequires: ocaml-findlib
+BuildRequires: dune
+
+%description
+OCaml promises and concurrent I/O.
+
+%package devel
+Group:         Development/Libraries/OCaml
+Summary:       Development files for %{name}
+Requires:      %{name} = %{?epoch:%epoch:}%{version}-%{release}
+
+%description devel
+This package contains libraries and signature files for developing applications that use %{name}.
+
+%debug_package
+
+%prep
+%setup -q -n lwt-%{version}
+
+sed -i '/test_mcast "mcast-join-loop"/d' 'test/unix/test_mcast.ml'
+
+# Don't buil lwt_domain
+rm -rf 'lwt_domain.opam'
+rm -rf {'src','test'}'/domain/'
+
+%build
+LWT_DISCOVER_ARGUMENTS='--use-libev true' dune build --release --verbose
+
+%install
+[ "%{buildroot}" != / ] && rm -rf "%{buildroot}"
+DESTDIR=%{buildroot} dune install --prefix "/usr" --libdir "%{_lib}/ocaml"
+
+rm -rf %{buildroot}/usr/doc
+
+%clean
+[ "%{buildroot}" != / ] && rm -rf "%{buildroot}"
+
+%files
+%defattr(-,root,root)
+%dir %{_libdir}/ocaml/%{ocamlpck}*
+%{_libdir}/ocaml/%{ocamlpck}*/*
+%exclude %{_libdir}/ocaml/%{ocamlpck}*/*.a
+%exclude %{_libdir}/ocaml/%{ocamlpck}*/*.cmx
+%exclude %{_libdir}/ocaml/%{ocamlpck}*/*.cmxa
+%exclude %{_libdir}/ocaml/%{ocamlpck}*/*.mli
+%{_libdir}/ocaml/stublibs/*.so*
+%doc LICENSE.md
+
+%files devel
+%defattr(-,root,root)
+%{_libdir}/ocaml/%{ocamlpck}*/*.a
+%{_libdir}/ocaml/%{ocamlpck}*/*.cmx
+%{_libdir}/ocaml/%{ocamlpck}*/*.cmxa
+%{_libdir}/ocaml/%{ocamlpck}*/*.mli
+%doc CHANGES README.md
+
+%changelog
+* Sun Jan 30 2022 Silvan Calarco <silvan.calarco@mambasoft.it> 5.5.0-1mamba
+- package created using the webbuild interface