Architecture
The architecture decisions of an API platform: internal and external topologies, gateway or service mesh, gateway families, protocols, the agentic layer, resilience.
Six decisions shape the architecture of an API platform. They are independent of the product chosen, they are taken early, and putting them off costs more than taking them imperfectly.
| Decision | The page |
|---|---|
| Who goes through which gateway, and in which zone | Internal and external |
| What governs the inside of the domain | Gateway and service mesh |
| Which families of traffic the platform must serve | The three gateways |
| What each protocol changes in the contract | Protocols |
| What a traffic of agents, tools and models changes | The agentic layer |
| How the whole holds together when a component degrades | Resilience |
One guardrail runs through all six: the platform applies rules, it does not host logic. If removing the gateway broke features, and not just security and control, too much lives inside it. The precise boundary is set out in mediation.
Updated August 2026.