diff --git a/python-singledispatch.spec b/python-singledispatch.spec
index c7c358a..2fe2738 100644
--- a/python-singledispatch.spec
+++ b/python-singledispatch.spec
@@ -1,17 +1,17 @@
+%define pkgname %(echo %name | cut -d- -f2- | tr - _)
 Name:          python-singledispatch
-Version:       3.7.0
+Version:       4.0.0
 Release:       1mamba
 Summary:       This library brings functools.singledispatch from Python 3.4 to Python 2.6
 Group:         System/Libraries
 Vendor:        openmamba
 Distribution:  openmamba
-Packager:      Davide Madrisan <davide.madrisan@gmail.com>
+Packager:      Silvan Calarco <silvan.calarco@mambasoft.it>
 URL:           https://pypi.org/project/singledispatch/
 Source:        https://pypi.debian.net/singledispatch/singledispatch-%{version}.tar.gz
 License:       MIT
 ## AUTOBUILDREQ-BEGIN
 BuildRequires: libpython3-devel
-BuildRequires: python3.7dist(six)
 ## AUTOBUILDREQ-END
 
 %description
@@ -25,26 +25,31 @@ BuildRequires: python3.7dist(six)
 %setup -q -n singledispatch-%{version}
 
 %build
-CFLAGS="%{optflags}" %{__python} setup.py build
+CFLAGS="%{optflags}" %{__python} -m build --no-isolation --wheel
 
 %install
 [ "%{buildroot}" != / ] && rm -rf "%{buildroot}"
-%{__python} setup.py install \
-   -O1 --skip-build \
-   --root="%{buildroot}" \
-   --install-headers=%{python_inc} \
-   --install-lib=%{python_sitearch} \
-   --record=%{name}.filelist
+%{__python} -m installer --destdir=%{buildroot} dist/*.whl
 
-sed -i "\,\.egg-info/,d;s,.*/man/.*,&.gz," %{name}.filelist
+#%if "%{?with_pyver}" != "3"
+## Rename any conflicting file outside of python site packages tree
+#for f in %{_bindir}/pdm; do
+#   mv %{buildroot}${f}{,-%{?pyappend}}
+#done
+#%endif
 
-%files %{?pyappend} -f %{name}.filelist
+%files %{?pyappend}
 %defattr(-,root,root)
-%dir %{python_sitearch}/singledispatch-*-py*.egg-info
-%{python_sitearch}/singledispatch-*-py*.egg-info/*
-%doc README.rst
+%dir %{python_sitelib}/%{pkgname}-%{version}.dist-info
+%{python_sitelib}/%{pkgname}-%{version}.dist-info/*
+%dir %{python_sitelib}/%{pkgname}
+%{python_sitelib}/%{pkgname}/*
+#%doc README.rst
 
 %changelog
+* Mon Mar 06 2023 Automatic Build System <autodist@mambasoft.it> 4.0.0-1mamba
+- automatic version update by autodist
+
 * Sat Aug 14 2021 Automatic Build System <autodist@mambasoft.it> 3.7.0-1mamba
 - automatic version update by autodist