Tell Me About a Time You Disagreed With a Technical Decision

This question looks like it's about the disagreement. It isn't. The interviewer wants to see how you handle being wrong, how you handle being right, and whether you can disagree without burning the relationship. The best answers end with you committing to a decision you argued against.

What they're really asking

Can you challenge a senior person or a popular idea using evidence instead of ego? Do you separate the technical merits from who proposed them? And once a call is made, do you get behind it or sulk? They are checking for maturity, not for stories where you won every argument.

How to structure your answer

STAR keeps you from rambling. Situation: set the scene in one or two sentences. Task: what was your role and what was at stake. Action: this is the bulk of the answer, what you actually did to make your case. Result: what happened, including what you learned. For a disagreement, spend most of your time on Action and be honest in Result. If the team went the other way and it worked out, say so. That's a stronger answer than pretending you were vindicated.

A sample answer

On my last team we were planning a rewrite of our dashboard from a tangle of jQuery widgets into React. The tech lead wanted a big-bang rewrite, ship the new dashboard all at once. I disagreed. The dashboard was our highest-traffic page and a full cutover felt risky. I pulled the analytics: about 40% of weekly active users hit that page, and we had no easy rollback if something broke.

I wrote a one-page doc proposing the strangler approach instead, migrating one widget at a time behind a feature flag. I walked the lead through it in our next sync. He pushed back on the overhead of running two stacks side by side, which was fair. We landed on a hybrid: incremental migration, but timeboxed to one quarter so it didn't drag.

It shipped on time with no major incidents, and we caught two layout regressions early because each widget went out behind a flag. The lead later used the same pattern for the settings page. The win wasn't getting my way. It was getting to a better plan than either of us started with.

What to avoid

• Picking a disagreement you obviously won, with the other person painted as foolish. It reads as ego.
• Leaving out the result, or having no measurable outcome. "We argued and then moved on" says nothing.
• Making it personal. Disagree with the decision, never the person.
• Refusing to ever commit. If you say you fought the call and stayed bitter after it was made, that's a red flag, not loyalty to your principles.