Kill Switch
ELI5 — The Vibe Check
A kill switch is a way to instantly disable a feature in production without deploying new code. Something breaks? Flip the kill switch and the feature vanishes. It's like having an ejection seat for your code. Every feature that could potentially break production should have a kill switch. The ones that don't are the ones that break at 3 AM on a Saturday.
Real Talk
A kill switch is a mechanism (typically a feature flag or configuration toggle) that allows instant disabling of a feature in production without code deployment. Kill switches are critical for managing production incidents, A/B test failures, and third-party service outages. They should be implemented for any feature with significant blast radius or external dependencies.
When You'll Hear This
"Hit the kill switch on the new checkout flow — conversion dropped 40%." / "Every feature flag should be a kill switch by default."
Related Terms
Blast Radius
Blast radius is how much damage something can cause when it goes wrong. A bug in a low-traffic admin page? Small blast radius.
Circuit Breaker
Circuit Breaker is like the electrical circuit breaker in your house.
Feature Flag
A Feature Flag is an on/off switch for a feature in your app, controlled without redeploying. You ship the code but keep the feature hidden behind a flag.
Incident
An incident is when something has gone wrong in production and users are affected.
Rollback
A rollback is the panic button. When you deploy something and it breaks production, you hit rollback and the system reverts to the last working version — l...