How do you judge a developer before hiring them?
Ask for something you can check without trusting them: live software you can use, source code you can read, a build you can run. Then judge the conversation: plain answers, honest about limits, keen to put things in your name. Charm is not evidence.
The longer answer
In practice.
The evidence test
Anyone can show screenshots. Live tools, public repositories and named
checkable claims are the difference between a portfolio and a story. Mine is
arranged for exactly this test, per
the engagement report,
and you should apply it to everyone including me.
The conversation tells
Good sign: they ask about your business before proposing technology, say "I
don't know" at least once, and volunteer what could go wrong. Bad sign: every
answer is yes, every timeline is fast, and the ownership question makes them
vague.
The small first job
Structure a real, small, paid piece of work as the interview: a repair, an
audit, one automation. How they scope, communicate and hand over tells you
everything a reference call cannot.
Same rabbit hole