Context
Our core platform needs to scale horizontally to support millions of concurrent connections, isolate high-load components (like ML inference serving and real-time streaming), and enable multiple teams to deploy their services independently without coordination blockages.
Decision
We will adopt a Microservices Architecture instead of a unified monolith. Each service will be responsible for a single domain (e.g., Shipment, Routing, Authentication, Billing), have its own database to ensure loose coupling, and run in isolated containers.
Consequences
- Pros:
- Independent scaling of resource-heavy services (e.g. ML inference requires GPUs, auth requires memory-focused DB caching).
- Isolated failure domains; a crash in route calculation does not bring down billing or user login.
- Team autonomy and faster development cycles.
- Cons:
- Increased network hop latency.
- Higher operational overhead (monitoring, distributed tracing, Kubernetes configuration).
- Complex transaction management (requires patterns like Saga or Outbox instead of local ACID transactions).