A supplier’s open source client library, read to answer one question, without learning the language first.
what was enough:
find the entry point named in the documentation
follow it, ignoring idiom and reading structure
find the one branch that looked relevant
confirm by changing it and running their tests
the question: does the client retry on a 429, and does
it respect Retry-After?
the answer: it retries, and it does not read the
header — it uses a fixed 1-second backoff.
which changed our rate limiting from optimistic to
deliberate.Reading unfamiliar code for one specific question is a different and more useful skill than being able to write the language, and the confirmation step is what makes it reliable — a hypothesis from reading is worth a great deal less than a hypothesis tested against their own test suite. Forty minutes, and it changed a configuration we had been guessing at.