The best way to write and contribute code is to create a git repo somewhere (e.g., github) for the repo you are interested in editing (e.g., `qubes-manager`, `core`, etc). To integrate your repo with the rest of Qubes, cd to the repo directory and add your repository as a remote in git
You can then proceed to easily develop in your own branches, pull in new commits from the dev branches, merge them, and eventually push to your own repo on github.
When you are ready to submit your changes to Qubes to be merged, push your changes, then create a signed git tag (using `git tag -s`). Finally, send a letter to the Qubes listserv describing the changes and including the link to your repository. Don't forget to include your public PGP key you use to sign your tags.
Now it is a good moment to make sure you have changed kernel release name in rel-pvops file. For example, if you change it to '1debug201211116c' the resulting RPMs will be named 'kernel-3.4.18-1debug20121116c.pvops.qubes.x86\_64.rpm'. This will help distinguish between different versions of the same package.
You might want to take a moment here to review (git diff, git status), commit your changes locally.
1.*make check* - will check if all the code was commited into repository and if all repository are tagged with signed tag.
2.*make show-vtags* - show version of each component (based on git tags) - mostly useful just before building ISO. **Note:** this will not show version for components containing changes since last version tag
3.*make push* - push change from **all** repositories to git server. You must set proper remotes (see above) for all repositories first.
4.*make prepare-merge* - fetch changes from remote repositories (can be specified on commandline via GIT\_SUBDIR or GIT\_REMOTE vars), (optionally) verify tags and show the changes. This do not merge the changes - there are left for review as FETCH\_HEAD ref. You can merge them using "git merge FETCH\_HEAD" (in each repo directory).
When developing it is convenient to be able to rapidly test changes. Assuming you're developing Qubes on Qubes, you should be working in a special VM for Qubes and occasionally you will want to transfer code or rpms back to dom0 for testing.
Here are some handy scripts Marek has shared to facilitate this.
