Git - How to Handle Emergency Deploy to Live Environment

Master always have our latest changes in our development and could be dirty and not production worthy. In order for us to do an emergency stable deploy to our live environment, it can be achieved as follow.

1. Suppose we have our Master M. On our last well known tag called mytag deployed to our live environment.
2. Subsequently C1 and C2 changes are commited to our Master.
3. And, we have an emergency deployment required for C3 change that needs to be pushed to live with out C1 and C2.

This can be achieved by the following.

# branch out to master-e from mytag
$ git checkout -b master-e mytag

# After committing change C3 to our new branch, we are then good for live deployment.
# Last thing to do is to apply C3 to Master Origin, so that our next deploy will have C3
# This can be achieved by a simple merge.
$ git checkout master
$ git merge master-e

The new branch master-e is then kept until the next master deploy, if we need other emergency deploys before our next master deploy, we can reuse master-e.