My manager is letting me choose between a couple options which project I want to work. What kinds of things should I look for to choose which project would be better for me in terms of becoming a better engineer and resume impact?
If it's possible, would you be able to post the different project options? We can go through the exercise of going through the pros and cons of each.
To make sure you are growing in your career, I would look at these signals:
A few criteria to consider:
I discuss finding the right team in the Senior to Staff course: Finding The Right Team.
Also, checkout the masterclass about team selection here.
Optimize for people.
When you're a junior engineer, you don't exactly know how to judge complicated things like technical complexity or evaluate a project's prospective impact (junior engineers are usually not judged for impact because of this).
What you do know (or should have some idea of) is how good/supportive a person is due to social intuition. For each of these projects, look at the other engineers attached to them and see which ones you have gotten along with the most. This is a very visceral exercise as you just have to listen to your gut and retrospect on vibes.
From there, go to the project with the people you like the most. Your goal as a junior engineer is to be a knowledge sponge and suck in as much learning as possible. That is 90% dependent on the people around you with just 10% being determined by the project itself.
If all the projects are solo projects, then just pick one with the technology/product domain you are most interested in. Optimize for passion so you can sustain energy over time.
Check out the junior to mid-level course as well: [Course] Grow From Junior To Mid-Level Engineer: L3 To L4