13 articles tagged with "microservices"
One slow downstream dependency can take your entire system down with it — unless something in the middle knows when to stop trying. Here's how circuit breakers actually work, and the timeout tuning mistake that nearly took our whole platform out.
Your order service and your payments service have been quietly changing behind each other's backs for months. Nobody noticed until a deploy on a Friday afternoon turned a 200 into a 500. Contract testing is the prenup you should have signed at the start of the relationship.
Your request touches six services and dies somewhere in the middle. Logs tell you nothing because nobody agreed on a request ID. Here's how OpenTelemetry turns that mystery into a single, followable story.
Your integration tests pass. Staging is green. Then a downstream team renames a field and production quietly starts dropping orders. Contract testing is how you catch that before it ships — without spinning up eleven services just to test one.
You broke the monolith into twelve services and now a single failed checkout produces twelve unrelated log lines in twelve places. Correlation IDs are the boring, cheap fix — here's how to actually wire them through, not just talk about them.
You can't BEGIN/COMMIT across five microservices. The saga pattern is how you fake it anyway — with compensations instead of rollbacks and a lot of humility about what \"consistent\" actually means.
Code coverage tells you which lines ran. It says nothing about whether your assertions would notice if the logic on those lines were wrong. Mutation testing fixes that by breaking your code on purpose — here's how it works and why your 'green' suite might be a green screen of nothing.
You configured sampling on every service. Each one is working exactly as designed. And yet your traces keep showing up with chunks missing, like a comic book where someone tore out every third page. Here's why, and how consistent sampling fixes it.
Your monolith had ROLLBACK. Your microservices don't. The saga pattern is how you fake a distributed transaction using nothing but events, compensating actions, and the quiet acceptance that everything is eventually consistent.
Everyone name-drops the circuit breaker pattern in system design interviews. Far fewer have actually tuned one that survives contact with production. Here's what the tutorials skip: half-open state thrash, per-dependency breakers, and why a breaker with no fallback is just a fancier 500.
The classic test pyramid assumes one codebase, one deploy, one team. Split that into fifteen services and the shape quietly stops making sense. Here's what actually works when 'integration' means 'a network call to someone else's team.'
Your unit tests pass, your integration tests pass, and then production breaks because Service A renamed a field that Service B depended on. Contract testing is the missing layer that catches this before it ships.
Distributed transactions are where microservices go to cry. The saga pattern gives you eventual consistency without locking every service in a two-phase commit death grip — here's how it actually works.