What makes an effective principal engineer or scientist? I distilled what I’ve learned from role models and included their direct advice which you’ll find quoted below. While my perspective is naturally Amazon-centric, these ideas should also apply to most principal tech IC roles. As always, use your best judgment and assess if this advice applies to you and your situation.
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1. Different principals will have different flavors. Some dive deep in one space while others excel at horizontal influence. Some are technical trailblazers who show how things are done, while others clarify complexity and illuminate the path forward. Still others are masters at aligning multiple orgs towards a common vision. No one flavor is more important than the other, and you need to find the flavor that plays to your strengths.
“Amazon very specifically says they want their principals hands on. I’ve spent a lot of time trying to dispel the notion that “PE’s don’t code”. Any principal who’s not being hands-on for an extended period of time (okay in short bursts) is likely setting themselves up for failure.”
2. The work that was core, and made you successful in your previous role, is now the side task. At this level, writing the code yourself may not be the best use of your time. While you should still be writing code (to stay connected to the work), your core role is now technical vision, design feedback, sponsorship, providing business, product, and technical context, finding new problems, connecting the dots, etc.
“This is a well-known saying for L7+ roles. It is not saying that you should spend less time coding, but that even if you are still coding 80% of the time, the most impactful part of your role is how to make everyone more effective. The mindset shifts from focusing solely on coding for a single project or perfecting on your own to influencing how all builders can build better across projects. This can be through contributing high-quality code to the repository and letting the code speak for itself, but also through other efforts—arguably more effective—such as giving feedback on design proposals, writing technical guidance, and driving the long-term vision.”
3. You’re kind of a part-time PM for technology. Scratch that, you’re part-time everything: product, design, engineering, science, quality assurance, hiring, finance, culture, etc. Nothing is not your job. The high judgment you have allows you to step out of your wheelhouse.
4. Your role will involve more communication, influence, and connecting the right people. Your projects will typically be larger in scope, involving teams across directors and even VPs. These projects won’t succeed without effective alignment and collaboration, and you’ll want to be careful not to ship your org chart to customers.
5. Being right is less than half the battle. You also have to convince others that you’re right, and more importantly, convince them to care enough to act on it. This means figuring out how to build momentum, who can sponsor the idea, and how to get it over the finish line.
“Sometimes it also means starting the project and showing value to gain these things. Principals should lead by example and we want people to be proactive in solving issues and not wait for committee.”
“I would almost say that principals are the committee, so who are you waiting for :)”
6. A big part of the work is teaching the org to value something it doesn’t care about. Your audience will range from executives to working-level ICs. This is some of the hardest work you can do, and it fails often, but as someone who has an eye on the future and broader view, you should still do it. A mentor shared that for every 10 docs he pitched, probably three would get acted on, and he considered that a great outcome.
“Compared to ICs who shoulder more of the day-to-day, team-level, and immediate deliverables, L7+ roles have more space to step back and take a broader, longer-term view of the company. It allows them to evaluate impact more objectively, and contributing at that level is where they add the most value—connecting to #7 below, those are the things that won’t happen without them.”
7. There’s a category of work that just won’t happen without you. It’s usually at the intersection of what you really care about and what you’re exceptional at. It could be building a quick prototype and socializing a new customer experience with leadership, building bridges across orgs or other practitioners in industry, or crafting the three-year vision. Focus on this category of work. Also, it’ll get deeper and narrower over the span of your career.
8. Sometimes, the most valuable thing you can do is not even to do the work but to connect the dots. This includes connecting teams who’re looking to do the work to teams who’ve done the work that they can reuse or learn from. It also includes identifying someone suitable who can do the work and grow along the way.
9. You can only do so much yourself. You’ll be more useful to the org spending part of the time coaching and mentoring others to be more effective. Perhaps set aside a few hours each week, such as office hours or regular syncs with folks you’re grooming. Identify one or two ICs you’d like to groom and set goals for yourself on how you’ll help them.
“Scaling through others is the key point here. I like to think the success of a PE is when the org is able to make the same decisions as the PE would. Then the PE moves on to other ambiguous problems and set the culture to achieve the right outcomes.”
“While you will want to help everyone, however you have to focus your energy on building others who can take your place long term. Not everyone has that ability so you have to spend focused time on those that you see demonstrating the potential to take over from you and they can in turn help others that show less potential at the moment and enable them.”
10. Transition from involving others in the work to making the work theirs. Make it an opportunity for someone to do the work that got you to where you are. Support and set them up for success. Don’t worry, there’s a never-ending backlog of important problems and interesting opportunities to work on for customers.
“I tell folks that they should spend 1-2 hours a week with someone to scale them to achieve 40 hours of work under your insights. This is what the true Principal scale is of being able to find those small things that enable a Sr SDE to be even better.”
11. When you give others the work, it is now theirs. You can provide context and guidance, but ultimately, the direction is theirs to set. This includes letting them take an approach you wouldn’t take. If it goes poorly, we all get to learn from it; if it goes well, you get to learn something from it. Nonetheless, you should step in if the project is walking through a high-risk, one-way door that could backfire.
12. Create space for others in meetings. Sometimes, the room looks to the most senior person for their opinion or decision; you can create space for others by asking questions instead. Also, if you see someone who’s not participating, gently pull them in on topics that play to their strengths. And if the meeting forgot someone who should have been in the discussion, add them to the next occurrence.
13. You don’t always have to demonstrate value. Some of the most effective principals I’ve worked with go through an entire meeting silent, or barely leave comments during document reviews. If the team and discussion are going fine as it is, that’s great! It means you can take a step back from the workstream and focus your energies elsewhere.
“Be careful on the other side of this: If you’re present and staying silent, you have some implicit approval. Beware of multi-tasking and what your presence means.”
14. In meetings with execs, it’s okay not to address every topic on the agenda. If they’re engaged in the topic, ask meaningful questions, and make the decisions or unblock the obstacles that only they can, that’s a good meeting.
15. Beware: If you work in a breadth role, your entire week can be filled with everything that comes at you. This includes reviews, escalations, emails, help needed, etc. This can become a bigger issue the longer you stay at an org, where you become the “go-to” person because you know so much or have earned that credibility. As a result, you’re now a “mandatory” attendee at every meeting. Learn to push back and guard your time, or else you’ll have no time to push for the ideas you really care about. The goal isn’t to be in every meeting or have an opinion on every idea, but to be fully present on the key ones that matter.
“One thing that a mentor shared with me is that you need time to think. If you are going from meeting to meeting, you can’t process things and can’t look ahead. You need to schedule quality thinking time and disconnect from meetings to really find that next big thing.”
“You need to look to delegate—set someone else up to be that person so that you can free up your time. This gives you benefits in freeing you up, but also helps put aside scope for someone new to help them grow.”
16. If you can’t explain why what you’re working on needs a principal, you might be working on the wrong thing. (This may also apply to L6s.)
17. Because of your position, you can sometimes improve outcomes with relatively low effort. The title grants you organizational privilege, and thus greater access to relationships and context. Combined with your experience, this allows you to see around corners better. Thus, you can meaningfully improve a project’s chances of success and outcomes by investing fairly little effort. This is high ROI, and when you spot such opportunities, act on them
18. The title comes with an aura of credibility even when you shouldn’t have it. Sometimes, people read more into your offhand comments than they should, especially if they don’t know you well. As a result, they may do a lot of work because of a casual comment you made. This can be a waste of time and effort. Thus, be clear on what you do know, what you don’t know, what you’re asking for, and what you’re simply commenting on.
19. Don’t just say the “what”; also share the “why” you think so. This helps others make better decisions. It also reduces the chance that others say “Principal <NAME> said this and thus we should …” and parrot things you said without fully understanding why you said it.
“The kinds of problems that require L7 input usually involve decisions under significant uncertainty. What’s crucial—but also difficult—is articulating your mental model: How you arrive at a judgment without having all the information, and why certain pieces of knowledge are more important than other data points.”
20. Find mechanisms to stay in touch with teams. This can be design reviews, weekly demos, sitting nearby and keeping an ear out, team lunches, or casual hallway chats. This helps you keep a pulse on the org and where the key problems or opportunities are.
21. Help teams keep sight of the bigger picture. When the working level is focused on the thick of things and day-to-day delivery, they can sometimes lose sight of the bigger, longer-term problems/opportunities and get stuck in the local optima. With the context that you have, you can help remind teams of this.
22. Be pragmatic; balance seeing the big picture and accepting local solutions. Consult and listen to the working level on the details; they’re your on-the-ground experts.
23. You’ll be asked for reviews or promo feedback on someone that you’ve only spent an hour or two with. It’s okay to decline instead of providing poor-quality feedback that’s based on a tiny sample of their entire behavior.
24. Make time to interact with interns and their mentors. A few touch points during the internship can be transformative, including an early check-in (and course correction if necessary) and being there for demo day. Also, work with the mentors and interns towards deliverables that continue to be valuable beyond the internship, where others can extend the project. This includes product 1-pagers, working software, and technical documentation.
25. To get to principal, you need to put yourself on the critical path. To be effective as a principal and go beyond it, you need to actively remove yourself from it. While you were previously the “go-to” person, you want to transition from essential to adjacent. The org should increasingly benefit from you, but shouldn’t be dependent on you to be effective. Think about how you can empower others to make the contributions you’re making.
“Be careful about injecting yourself in critical path projects. Your focus is a lot more prone to being stolen by some other priority, so you need to keep yourself out of the critical path or be really stringent about locking down if you are in the critical path.”
26. If you were promoted to principal, it’s because you’ve been acting as a principal for a while. Typically, for more than a year. Thus, don’t worry about the increased expectation of the title. Just keep doing what you’re doing, engage with other principals, figure out your style, and work with your leadership to identify your focus areas.
27. With great freedom comes great responsibility. You have the autonomy to choose what to work on, but there’s the expectation of accountability and impact. The freedom isn’t about doing what you want, but ownership of finding the highest leverage problems to solve. Don’t expect to be told what to do or be given any guidance. You’re expected to figure out what the org should focus on.
28. Define and align your charter with your leadership. One way is to split your work into three buckets: (i) owner, (ii) sponsor, (iii) consultant. As a consultant, you’re involved in reviews and provide guidance, and have a high-level understanding of the system’s or product’s intent. As a sponsor, in addition to the above, you make the idea a priority for the org, work to build alignment and drive decisions, and engage with stakeholders. As an owner, it’s everything above, plus being the system expert and first point of contact, and having borderline obsession with the success of the design, execution, and impact. I tend to own 1 - 2 projects (> 50% time), sponsor 2 - 3 projects (~20% time), and consult the rest of my time.
29. Being a principal can be lonely. You’re part of all teams but also part of none. Build a network of peers with whom you can have open conversations. It likely doesn’t matter if you’re working on the same domain or even in the same company.
30. Don’t neglect your own needs. Make time and space for projects that support your learning, growth, and wellbeing. While it can feel selfish in the short term, it’s far more preferable to you burning out on the org. If you’re actively looking for work that keeps you healthy and happy and growing, your org benefits too, and it’s easier for them to retain you. Work with your manager on how to balance this.
31. Keep learning; our industry moves fast. If you take on projects that teach you nothing, or at least nothing relevant to your work, you’re moving backwards. This is sometimes inevitable—timebox such projects when they come along. Also, your learning doesn’t have to solely come from the job. I know PEs who find time to read papers and technical textbooks, and hack on prototypes over weekends to better understand new ideas and technology.
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Thanks to Brian K, Tim L, Yiwen O, Prannoy C, Aman A, Dennis T, and others for reading an early draft and providing feedback. And thanks to my mentor and role model, David S.
If you found this useful, please cite this write-up as:
Yan, Ziyou. (Oct 2025). Advice for New Principal Tech ICs (i.e., Notes to Myself). eugeneyan.com. https://eugeneyan.com/writing/principal/.
or
@article{yan2025principal,
title = {Advice for New Principal Tech ICs (i.e., Notes to Myself)},
author = {Yan, Ziyou},
journal = {eugeneyan.com},
year = {2025},
month = {Oct},
url = {https://eugeneyan.com/writing/principal/}
}
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