How do I prove to my manager I deserve a promotion to E4? Or above a meets all rating?

I think someone from Meta can offer more precise advise, but maybe you'll find these helpful since this generally maps to other big tech companies as well:

1. At Google, The main difference between Level 3 and Level 4 is independence. Meeting expectation at L3 means you are doing everything you are told to do. At Level 4, you would be expected to figure out more of what you need to do on your own, especially from an implementation perspective. E.g. You are trying to implement logic A, get it to work but change doesn't really fit the intent of the surrounding code - L3 would probably submit it for review soon after, but a good L4 will take some time to maybe do a refactor first then send the code logic change.
2. If you manager is new and isn't able to clearly explain to you what performing at the next level would look like, it may be best to find a more senior team member who's able to show you what that would look like. What is the code velocity of the average level 4 engineer on your team look like? How about the best level 4 engineer? Coming close to their levels and learning from them how to do it would likely go a long way.
   1. Caveat here: you also don't want to focus on Code Velocity too much (it's more of trailing indicator for how effective you are at implementation) - it's more important to figure out how the top performers on your team are able to move so fast, rather than trying to brute force this.

Good luck!

@Senior SWE at Google is spot on.

One tactic to get more concrete feedback from your manager is to make an attempt at what an EE rating would look like.

So in your next 1:1 (or perhaps you have a separate dedicated 1:1 to add more weight to the discussion), you can bring some ideas.

Based on what we talked about, here's how I'm thinking about what it would mean to hit MA, EE, and GE for each project. I'd love your feedback if I'm thinking about this in the right way.

Make each rating bucket very clear and, ideally, quantifiable (something like "Finish project X 3 weeks ahead of schedule and 4 other developers using the tool by end of half"). Be open to feedback, suggesting this as a starting point rather than a contract you want your manager to agree to.

This is the principle of "people like correcting things more than they like helping" :) I'm not saying your manager is bad, but this is a way to lower the activation energy to get feedback.

@Rahul Pandey As an E3 engineer, what quantifiable metrics would be best to make those buckets? As business impact at our level does not matter too much, is "finishing project 3 weeks early" probably a better metric for me to hit than "get 20 more engineers to use my new tool"?

A more broader question would be: what stands out as an E3 engineer to get a EE/GE?