The Foundation of High-Performing Teams: Psychological Safety
Google's Project Aristotle famously found that the #1 predictor of a high-performing team wasn't skills, experience, or seniority. It was psychological safety.
In an engineering context, this means:
- Can I admit I don't understand this legacy code?
- Can I point out a flaw in the Senior Architect's plan?
- Can I admit I made a mistake that brought down production?
If the answer is "no," your team is operating far below its potential.
The Cost of Silence
When engineers don't feel safe, they:
- Hide bugs until they are unfixable.
- Over-engineer solutions to avoid criticism.
- Stop innovating because the "risk" of failure is too high.
- Burn out from the stress of maintaining a "perfect" facade.
How Managers Build (or Break) Safety
Psychological safety is fragile. It takes months to build and seconds to destroy.
1. Model Vulnerability
If you want your team to admit mistakes, you must admit yours. "I totally misjudged the complexity of that integration, and that's on me. Let's talk about how we can adjust." This gives the team permission to be human.
2. The Blameless Post-mortem
When things go wrong—and they will—focus on the system, not the person. "How did our testing suite allow this to pass?" is a safety-building question. "Who approved this PR?" is a safety-breaking question.
3. Normalize "I Don't Know"
Protect the junior engineers. When someone asks a "dumb" question, validate it. "That's a great question. Even I find that part of the codebase confusing."
Measuring the Invisible
How do you know if your team is safe?
- Participation: Everyone (not just the loudest) contributes in meetings.
- Pushback: People disagree with you or each other openly and respectfully.
- Failures: Small failures are caught and discussed early.
Documenting Growth moments
When someone shows vulnerability or admits a mistake, recognize it. In your 1:1, say "I really appreciated you speaking up in the meeting today about the potential risks in the project. That saved us a lot of pain later."
Capture these moments of "leadership through honesty" in your notes. These are the behavioral traits that define a senior engineer.
Conclusion
Psychological safety isn't about being "nice" or "soft." It's about creating an environment where the truth can be told. And in engineering, the truth is the only way to build reliable systems.
About the Author
Carlos Corrêa da Silva is an Engineering Manager and the builder of Ledger, a tool designed to help engineering managers maintain context on their teams. He focuses on making people management more systematic and less reliant on memory.