Reference checks predict performance when you make them structured and comparative, asking a former manager to rank the candidate against peers and describe specific behavior, instead of inviting generic praise. The default 'would you rehire them?' call is theater; the structured version is nearly free signal.
Questions that produce signal
- 1'Compared to all engineers you've managed, where does this person rank, top 5%, 10%, 25%?' Force a number.
- 2'Tell me about a specific project they owned end to end. What was their actual contribution?'
- 3'What kind of environment brings out their worst work?' Everyone has one; evasion is a flag.
- 4'If they joined your team again tomorrow, what role would you put them in?' Compare it to yours.
- 5'Who else saw their work closely?' A great reference volunteers more names.
How to read the answers
- Enthusiasm gaps: references for strong performers interrupt you with stories; tepid references answer only what's asked.
- Faint praise ('reliable', 'pleasant') on questions about impact usually means average.
- Specifics are the currency, a reference who can't name a concrete project saw the work from a distance.
- One lukewarm reference among strong ones is noise; a pattern is data.
