A field guide to the mental shortcuts that quietly steer estimates, code reviews, debugging sessions, incident response, and hiring decisions — written for engineers, not psychologists.
General "list of cognitive biases" resources are everywhere, but most are written for a general audience: abstract definitions, no connection to the work you actually do. This repo skips the abstraction. Every entry answers one question: what does this bias look like on a real engineering team, and what do you actually do about it?
- What it is — a one-line, jargon-free definition.
- How it shows up — a concrete scenario from estimation, review, debugging, or team process.
- Warning signs — phrases and situations that suggest the bias is active.
- Mitigation — a concrete counter-move, not just "be aware of it."
| Category | Biases covered |
|---|---|
| Estimation & Planning | Planning Fallacy, Anchoring, Optimism Bias, Sunk Cost Fallacy |
| Code Review & Design | Confirmation Bias, Not Invented Here, IKEA Effect, Bikeshedding |
| Debugging & Incidents | Availability Heuristic, Hindsight Bias, Curse of Knowledge, Fundamental Attribution Error |
| Team & Process | Groupthink, Bandwagon Effect, Status Quo Bias, Survivorship Bias |
| Hiring & Management | Halo Effect, Affinity Bias, Dunning-Kruger Effect, Recency Bias |
- Engineers who want a sharper eye during code review or design discussions.
- Tech leads running estimation, retros, or incident postmortems.
- Anyone building a hiring loop who wants to notice their own shortcuts.
A few ways teams have found this useful in practice:
- Pin the relevant category's link in your sprint-planning or postmortem doc template as a pre-read.
- Pick one bias per retro and ask, "did this show up for us this cycle?"
- During interviewer calibration, walk through the Hiring & Management entries before debrief.
Corrections, sharper examples, and new bias entries (with a genuine engineering-specific scenario, not a generic one) are welcome via PR. Keep new entries in the same four-part structure.
Content is available under CC BY 4.0 — reuse and adapt freely, with attribution.