Navigating Medical Leave and Performance Ratings: A Strategic Approach

Your health comes first! I feel like you're worrying too much about your rating, especially given the circumstances (not taking a proper break for 2 years is really rough and will burn you out). If you're at a "Tier 2" company, there really isn't a meaningful difference in pay, clout, etc from getting 4/5 instead of 3/5.

That being said, it's still important to care about your rating, particularly with avoiding a below average rating/PIP. Some thoughts here:

• Come up with a plan to replace yourself - 4 to 6 weeks is a long time, and as a senior engineer, I imagine you have a lot of scope. Make sure that your current workstreams don't fall apart when you're out. I would write a document for my manager/team whenever I was out for >1 week (things move fast at Meta!). Some more good thoughts on taking extended PTO here: "How much PTO should I take?"
• Talk to your manager - Figure out if you're closer to 3/5 or 4/5 and define the requirements to hit 4/5. Once your manager is aware of the medical leave, ask them how it affects the trajectory. It will probably be awkward leading the conversation to such a transparent and honest state, but that's simply what you need to do when it comes to disambiguating performance. More advice on all of this here: [Masterclass] How To Work Better With Your Engineering Manager
• Take your leave ASAP
  • Reason #1: You're almost certainly suffering from burnout.
  • Reason #2: Recency bias is huge for performance review. If you take leave next week and come back in mid-February, hopefully you can crush it in the remaining time before April to bump up your rating.

Best of luck - I hope your leave is really helpful for your long-term health!

I question the wisdom of deferring my health needs for the sake of a rating

Hard to argue with this logic. Your health is more important than your work. However, the nuance is that neither of these are binary options.

A few things to consider:

• What company do you work for now? If you're at a FAANG-adjacent company, the brand/career lift from FAANG won't be very high.
• Is there something you can accomplish before the end of the perf cycle that will will help you in your next round of interviews?
• Can you lightly bring up the topic from your manager about taking a leave, and what your options are?

See also these related discussions about asking for extended time off:

• Seeking FLMA because of stress and anxiety, how to apply?
• How to ask for extended time off?

How can I bring up the gap between 3 and 4 rating, and my medical leave with my manager?

I'd decouple these conversations. First get clarity on how you're trending for your performance review. (hopefully you have like a monthly career check-in)

Several weeks (or at least days) later, you can bring up the medical leave.

I’m at a tier 2 company. Not a FAANG currently.

I don’t think my current/ future ratings will help with landing a new job in the future. As it will be a fresh start at a new company.

however, I do care about my performance here, and want to be seen as a highly effective contributor. How can I bring up the gap between 3 and 4 rating, and my medical leave with my manager?

Thank you for the valuable advice!