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+# Hacking Guide
+
+## Setup the development environment
+
+Pre-requisites:
+
+- Fedora 34 or higher
+- mock
+- rpmdevtools
+- rpm-build
+- git (with LFS enabled)
+- createrepo
+- rsync
+- rclone
+
+```sh
+cd ~
+git clone https://github.com/nmasse-itix/dhclient-orange.git rpmbuild
+```
+
+See https://rpm-packaging-guide.github.io/
+
+## Building
+
+```sh
+cd ~/rpmbuild
+rpm -Uvh SRPMS/dhcp-*.src.rpm
+git checkout -- SPECS/dhcp.spec
+./build.sh
+./release.sh
+```
+
+## Backport new version of dhclient
+
+On a CentOS Steam machine:
+
+```sh
+cd /tmp
+dnf download dhcp --source
+```
+
+And then, on your development machine:
+
+```sh
+scp centos-stream-machine:/tmp/dhcp-*.src.rpm SOURCES
+rpm -Uvh SOURCES/dhcp-x.y.z-patch.src.rpm
+```
+
+Do a git diff to see potential changes against current version.
+Do not forget to:
+
+- change the version/release from x.y.z-t to x.y.z-t.itix1
+- change the package name from client to client-orange-isp
+- re-add the patch "dhcp-orange-fibre.patch"
+
+```sh
+./build.sh
+./release.sh
+```