Add customer critical merge request process

doc/development/code_review.md

@@ -468,6 +468,21 @@ When a merge request author has been blocked for longer than
 the `Review-response` SLO, they are free to remind the reviewer through Slack or assign
 another reviewer.
 
+#### Customer critical merge requests
+
+A merge request may benefit from being considered a customer critical priority because there is a significant benefit to the business in doing so.
+
+Properties of customer critical merge requests:
+
+- The [Senior Director of Development](https://about.gitlab.com/job-families/engineering/engineering-management/#senior-director-engineering) [@clefelhocz1](https://gitlab.com/clefelhocz1) is the DRI for deciding if a merge request will be customer critical.
+- The DRI will assign the `customer-critical-merge-request` label to the merge request.
+- It is required that the reviewer(s) and maintainer(s) involved with a customer critical merge request are engaged as soon as this decision is made.
+- It is required to prioritize work for those involved on a customer critical merge request so that they have the time available necessary to focus on it.
+- It is required to adhere to GitLab [values](https://about.gitlab.com/handbook/values.md) and processes when working on customer critical merge requests, taking particular note of family and friends first/work second, definition of done, iteration, and release when it's ready.
+- Customer critical merge requests are required to not reduce security, introduce data-loss risk, reduce availability, nor break existing functionality per the process for [prioritizing technical decisions](https://about.gitlab.com/handbook/engineering/#prioritizing-technical-decisions.md).
+- On customer critical requests, it is _recommended_ that those involved _consider_ coordinating synchronously (Zoom, Slack) in addition to asynchronously (merge requests comments) if they believe this will reduce elapsed time to merge even though this _may_ sacrifice [efficiency](https://about.gitlab.com/company/culture/all-remote/asynchronous/#evaluating-efficiency.md).
+- After a customer critical merge request is merged, a retrospective must be completed with the intention of reducing the frequency of future customer critical merge requests.
+
 ## Examples
 
 How code reviews are conducted can surprise new contributors. Here are some examples of code reviews that should help to orient you as to what to expect.