The tax portal's invoice service hard-codes direct HTTPS calls and shared database tables into the payment service, so either team's change breaks the other at deploy time. What problem is this, and what direction improves it?
Select an answer to reveal the explanation.
Short Explanation
When invoice and payment share tables and call each other like they share a cubicle wall, you have tight coupling — one sneeze and both catch a cold at deploy time. Loosen that with queues or events and clear API contracts. Then each team can ship without freezing the other.
Full Explanation
Tight coupling appears as shared schemas, hard-coded synchronous dependencies, and coordinated releases. Loose coupling uses asynchronous messaging, published events, or stable versioned interfaces so services evolve independently. Merging into one binary increases coupling. Shared tables do not create isolation, and removing API Gateway does not address the root coupling between invoice and payment.