How do you give feedback to more senior engineers and managers?

I'm going to make an entire course about giving and receiving feedback, but in the meantime, check this out: The Core Principles Behind Writing Great Performance Review Feedback

Writing feedback for very senior peers as a relatively junior person is hard, especially the constructive portion. Here's my advice:

• Don't feel pressured to provide constructive feedback - As an SDE 1, you are still trying to master the expectations at your own level, let alone understand what it means to be a high-performing SDE 2, SDE 3, or SDM. If you can't come up with any areas of improvement for your very senior peers, that's totally fine.
• It's about good -> great, not bad -> good - If someone is legitimately doing something bad (e.g. their code is super messy and breaks all the time), you shouldn't wait until the performance review formal feedback mechanisms drop to share that. You should deliver that feedback to them ASAP through your manager. When it comes to the more formal tools, think about what your teammates are doing well (it seems like your team is great, so I imagine there's a lot here) and how they can do it even better. For example, let's say your teammate has been really good at helping you directly write automated tests. You can give feedback on how they can level up by taking their automated testing knowledge and making it more available to the team via a testing wiki.
• Create positive energy - The feedback mechanism isn't just a tool to share feedback, it's also a tool to build up relationships and just add more positive vibes into the world. It seems like you enjoy working with your team - Show your gratitude! Don't be afraid to be a bit "mushy" and write something extremely vibrant, positive, and happy for your teammates. Strive to write something heartwarming for those who have helped you the most. It is impossible to appreciate someone too much.

Hope this helps!

Something I did as a manager, but should have done as an IC as well, is to have a dedicated Google Doc for each person on my team. I'd put observations about that person in their assigned doc, things like:

• They led this meeting really well or
• This presentation was very confusing or
• I'm not sure what this person is working on now

Having this doc and having a few bullet points accumulated throughout the year makes it much easier to provide meaningful feedback when asked.

A really good discussion I'd recommend you go through: How do I give feedback to my manager? To add to that:

• I really like Alex's point about "It's about good -> great, not bad -> good." Feedback doesn't have to be constructive, it can be "you're doing this thing that I really admire, please do more of it!"
• Another tactic is to flip the question back at these senior folks. Ask them what their goals are and what are the areas they want feedback on. This can help you focus on those areas in your interaction with them in the future.