What is Principal Engineer role?
A principal engineer usually means one of the most experienced individual contributors in the organisation. It’s an ultimate step in the engineer career ladder that gives great recognition for folks in that role but also the highest expectations for their performance. Being principal engineer is not an easy task and everyone who is on the trajectory to get there should embrace the big shift of what is the most impactful and valuable for such an experienced role - leadership over execution.
Disclaimer: this is not official guidance that we use at Intercom. There is a big overlap, but there is plenty of my opinions here that never were (or not yet) solidified at Intercom.
Elevator pitch
A principal engineer is the most experienced individual contributor. However, it’s a big gap between senior engineer and this level. It is not a linear progression of technical skillset. It’s better to say that it’s one of the most experienced leaders in the organisation that has flexed ability and space to go deep in engineering.
Principal engineers should be partnering with a consistent set of teams over time. Similarly to other leadership positions like director of engineering, it takes months to see the change and long-term impact of a leader. If they move around the org too often, there is a risk that they will act more like expert executor, not a strategic leader.
Leadership
A principal engineer is first and foremost a leadership position. They should focus on the strategic area that almost always will map to multiple teams. These areas will often be formalised as groups - your organisational structure almost certainly represents strategic areas.
This leadership is backed by feedback on every level - you will hear this from junior engineer collaborating with a principal for a few weeks and from their experienced engineering manager at the same time.
They are principal engineers but they don’t work in silos. They make sure that we build cohesive strategies and execution and to do this, they need to make sure that product, design and business are aligned too. They are able to lead through functions or at least partner with and get alignment through more organisation focused leader like a director of engineering.
You will often see principal on the front line of the company. AMAs, All Hands, demos, wide audience and targeted audience for leadership - principals should speak and communicate publicly and should be visible. They are inspiring and people need to get inspired.
They often proactively pair with engineers in multiple teams to introduce patterns and technologies that they advocate for. Principal engineers are role modelling the way your company approach engineering, following your principles, values and culture. You can see their name on numerous tech design working groups, code reviews or see them whiteboarding a problem with a few folks in the room. They make sure they follow your processes and whenever these processes stop working from them, they recommend and incorporate changes across the organisation, instead of abandoning it.
Autonomy
A principal engineer has full autonomy with excellent communication structure. It’s a lonely job. There is no one to tell them exactly what to do. There is no one to delegate work to them. It’s them who tells others what they work on, and they do it really well so other engineering leaders are fully aware.
A principal engineer will often have multiple projects happening at the same time. Some of them are going slow, some of them are going faster, some of them are paused. Creating the strategy is a long term process and in most of the cases starts from a challenge - an anticipation of future problems. They acknowledge the fact that to understand the priorities and impact of strategic problems, they need research.
A principal engineer proactively spends some of their time outside of critical path, looking for and identifying impactful problems. They know when to be hands-on and spend more capacity executing on a current critical project and when to delegate.
They have a strong network of relationships, also on the leadership level, that is actively maintained.
Growth and inclusiveness
Principal engineers coach teams and individuals. You could pair a senior engineer with any other IC and should expect a good coaching relationship and growth of the coachee. You would pair a principal engineer to a team and you would expect the whole team outcomes to be better. Sometimes it means coaching managers, sometimes senior engineers, sometimes being way more hands-on and playing a role model job.
Principal engineers are considered key partners in engineers growth on all levels. They are fully aware of the weight of their opinions and are objective, fair, transparent and inclusive. They can expertly flag any dysfunctions of teams, managers and individuals. They don’t have to be able to address them or successfully identify a root cause. Last but not least, the quality of their feedback is great.
Hope that helps!
If you are looking for more resources, there is an excellent post by Will Larson with plenty of additional resources. I would particularly highlight this one from Keavy McMinn which helped me put some of my thoughts to words.
