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+## About
+
+srczap manages a local copy of the
+[HardenedBSD source code](https://git.hardenedbsd.org/hardenedbsd/HardenedBSD).
+The copy of the source tree is maintained by members of
+the `_srczap` group, and a copy of the source tree
+can be installed to `/usr/src/` by root.
+
+## Examples
+
+### CLI: setup-srczap
+
+This command should be run after installing srczap for
+the first time.
+
+    # Add the srczap user, group and home directory.
+    # This command requires root privileges.
+    # setup-srczap
+
+### CLI: srczap
+
+
+    # Clone the HardenedBSD source code into /home/_srczap/src/.
+    # This command is delegated to the '_srczap' user.
+    $ srczap clone
+
+    # Pull updates into /home/_srczap/src/.
+    # This command is delegated to the '_srczap' user.
+    $ srczap pull
+
+    # Install /home/_srczap/src/ into /usr/src/.
+    # This command requires root privileges.
+    # srczap install
+
+    # Start over: erase /usr/src/ and /home/_srczap/src/.
+    # This command requires root privileges.
+    $ srczap erase
+
+
+### ENVIRONMENT
+
+* __$SRCZAP\_GITURL__ <br>
+  The URL to a git repository.  <br>
+  Default: https://git.hardenedbsd.org/hardenedbsd/HardenedBSD.git.
+
+* __$SRCZAP\_BRANCH__ <br>
+  The git branch to clone and pull updates from. <br>
+  Default: hardened/14-stable/master.
+
+* __$SRCZAP\_INSTALLDIR__ <br>
+  The directory where the source tree will be installed. <br>
+  Default: /usr/src/.
+
+## Install
+
+**Source**
+
+The most recent version of srczap can be installed directly
+via git:
+
+    $ git clone https://github.com/0x1eef/srczap.git
+    $ cd srczap
+    # make install
+    # srczap setup
+    # pw groupmod -n _srczap -m <user>
+
+## Requirements
+
+* [doas](https://man.openbsd.org/doas) (`pkg install doas`)
+* [git](https://www.man7.org/linux/man-pages/man1/git.1.html) (`pkg install git`)
+
+## Sources
+
+* [GitHub](https://github.com/0x1eef/srczap)
+* [GitLab](https://gitlab.com/0x1eef/srczap)
+* [git.hardenedbsd.org](https://git.hardenedbsd.org/0x1eef/srczap)
+
+## License
+
+[BSD Zero Clause](https://choosealicense.com/licenses/0bsd/). <br>
+See [LICENSE](./LICENSE).