Microservices are services bounded by business capability, each owning its own data store, independently deployable and independently scalable. The hard parts are the boundaries between them: what talks sync vs. async, how consistency is kept without distributed transactions, and how failures in one service don’t cascade into all of them.
Core definition#
Services bounded by business capability, each owning its own data store, independently deployable and independently scalable. “Database-per-service” — no service reaches directly into another’s database — is the load-bearing rule that makes independent deployability actually hold; a shared DB across services re-couples them even if the code is split.
