What are the expectations of a strong senior engineer?

Alex has a very good mid-level to senior growth plan that you can find in Slack (it's a fairly long PDF). Even with the description though, it may not be super actionable.

What I'd recommend is for you to propose a few projects and the scope of work, and then ask the concrete question "How do you think this work I have planned ladders up to a senior promotion in the next performance cycle?" (or w/e the timeline is)

A few of the points that stand out to me regarding what senior means:

• You tackle projects at the 3-9 month time horizon. You should have a fairly good idea of the project and what stage it'll be in, several months out.
• You are trusted + efficient in writing code and, perhaps more importantly, in reviewing other people's code as well.
• The work you do is high impact and people look to you for direction in your area.

I'd also ask questions about the different ways engineers at Target are assessed (e.g. mentorship, code velocity, direction-setting, etc).

Here's the growth plan Rahul alluded to: Meta E4 -> E5 Growth Plan

It is the growth plan that I shared with all my E4 (Meta mid-level) mentees to help them get to E5 (Meta senior-level). It's one of my proudest works and feedback around this document has been great, but there's a couple caveats using it for your situation:

• Every company is different - This means that how companies view engineering culture and judge SWE performance are going to be different, and I imagine there's big gaps between Target and Meta as they are fundamentally different companies. Spend a lot of time observing strong L5s in your team/org - You can even ask your manager on who they believe are solid L5s to emulate.
• Meta is very people-skills driven - Target is big, but Meta is an order of magnitude larger, so this will make communication much more important at Meta in general. Also, Meta prides itself on its open culture, making people-skills even more important. I feel like most other tech companies are more technical than Meta are when it comes to SWE expectations (i.e. senior+ engineers will spend more of their time coding), and this will reflect in senior engineer expectations.

On top of the Meta E4 -> E5 growth plan, I also heavily recommend this Q&A from a mid-level Microsoft engineer to understand what senior scope looks like: "How to identify projects that are more suitable for senior engineers?"

Going back to the original question, there's a lot to unpack here (the senior promotion is generally a tough one), so I'll just add something from my experience that I found useful in understanding what it means to be a senior engineer (with the definition I worked with across Meta and Robinhood).

I joined Instagram as a mid-level engineer. One piece of advice my 1st manager at IG gave me in helping me grow to senior is they told me to observe and learn from a stellar senior engineer on my team, who was an iOS tech lead. My manager told me that they could just give this iOS engineer a few sentences like "Allow advertisers to add a polling sticker to Instagram story ads", and this engineer would just "magically" handle it all without my manager having to worry. This means that this engineer would do things like:

• Sync up with the PM and designer to create a product spec and mocks for this project
• Gather the necessary engineers (iOS, Android, back-end, and web) to build up the team
• Define the timeline
• Write project updates and clear out blockers proactively
• Create the technical strategy and get alignment on it

They would do all of this with 0 hand-holding and essentially act as an "API" our manager could call to deliver a large month project end-to-end with our manager having peace of mind the entire time.

To me, that's what a competent senior engineer looks like: Someone who can take an extremely ambiguous 6-9 month project and deliver it all on-time and with high-quality as the primary leader.