Sometimes I catch myself second-guessing a critical technical decision or feeling overwhelmed on a project I donāt fully understand. Thatās usually a sign that Iām operating beyond my circle of competence.
For me, that circle isnāt just what I know on paperāitās where Iām fluent. Itās where I move fast, trust my instincts, and know the difference between whatās knowable and whatās just uncertainty I canāt eliminate. When I can name my unknowns with confidence, I know Iām in the zone. Thatās one of the biggest edges you get as a senior engineer: sharper decisions, fewer unforced errors, more trust from your team.
A circle of competence is a living thing, built slowly through years of experience, a few hard-won mistakes, and relentless curiosity. For me, it starts with being honest about where people already rely on me. Thatās usually the core. Then I try to name three things: what I know well, what I know I donāt know, and whatās just unknowable. If I can clearly name all three, I know Iām inside my circle. If I canāt, thatās an edge worth exploring.
One way I keep that circle sharp is by returning to fundamentals. Trends fade fast. Fundamentals donāt. I often revisit the basics of my domain, such as the CAP theorem for distributed systems or queuing theory for performance, and rederive them as if I were explaining them to a beginner. It keeps my foundation solid even as tools and frameworks shift.
Growth doesnāt happen by accident, either. I block time each week to dig into something new: reading papers, exploring source code, or hacking together quick throwaway prototypes. Once a year, I take on one project that truly challenges me. And I share what I learnāwhether through design documents, talks, or blog postsābecause teaching forces clarity and multiplies your impact.
Iāve also started treating myself like a system. After every project, I log my assumptions, key decisions, and outcomes. Did the latency drop I expected actually happen? If not, why? Over time, patterns emergeāsuch as my tendency to underestimate complexity in certain areas. Tracking that stuff compounds into better judgment.
One thing Iāve learned the hard way is that seniority can create blind spots. Every quarter, I ask peers what they see: āWhat am I missing? Where am I weak?ā Itās uncomfortable, but Iāve never done it without learning something useful. And before chasing shiny new skills, I check whether they actually help the team and companyāfaster, safer, cheaper.
None of this works if the ego takes over. Ego-driven choices create blind spots; competence-driven ones create leverage. When something fails, I try to treat it as data: what went wrong, why, and what Iāll do differently next time. The key is to keep failures small enough to survive and continue learning.
The way I make it all stick is simple. Every month, I take a few minutes to reflect on recent decisions and mistakesāwhat worked, what didnātāand write it down. Each quarter, I check in with peers and look for patterns. Once a year, I revisit fundamentals and challenge myself with a single complex project. No fancy tools requiredājust a notebook, a document, or a calendar reminder. The habit is what matters.
For me, the payoff has been tremendous. A clear circle of competence enables me to make faster, smarter decisions, avoid overconfidence traps, grow in ways that truly matter to the organization, and scale my impact through teaching and collaboration. It doesnāt happen overnight, but it compounds over time.
Not sure where to start? Write down one strength, one gap, and one genuine unknown. Thatās your foundation. Start there today and keep at itāit pays off for years to come.