Seniority is not a checklist
A senior engineer is not simply someone who knows more APIs. Seniority shows up in how a person frames uncertainty, protects constraints, and helps others make better decisions.
Mentor around real decisions
The strongest mentoring happens around live work: how to split a service, when to avoid a dependency, how to communicate risk, and how to keep delivery moving without hiding weak assumptions.
Weak feedback
"Make it cleaner."
Useful feedback
"This boundary makes rollback depend on two teams. Name that trade-off in the design note."
Useful feedback loops
Growth accelerates when feedback is specific. Review one design note, one pull request, one incident, and then name the pattern behind the work.