Middleware, Instrumentation & Production Notes

Planned page

This is the fourth and final page of the Fastify framework track. Its detailed walkthrough will be added in a later brief. It builds on the Tenant-Aware API and Transaction Continuity pages.

Purpose

Demonstrate that the same Ambiten runtime policies remain useful when the HTTP framework changes from Express to Fastify.

Planned scope

• Reuse model middleware and lifecycle behavior without depending on Fastify request objects.
• Preserve tenant and request identity in execution-scoped instrumentation.
• Distinguish Fastify transport hooks from Ambiten model-operation middleware.
• Keep shared clients, tenant infrastructure, and configuration at process lifetime.
• Define startup, readiness, error handling, request draining, and shutdown responsibilities.
• Describe trusted tenant selection and authorization boundaries before production deployment.

Target checkpoint

The application should preserve its model policies and instrumentation while Fastify owns transport behavior. Resource cleanup belongs to the process lifecycle, and request-specific state must remain scoped to its execution.

This page will consolidate the framework change, not reproduce the entire Production Runtime tutorial or claim that adapter installation alone makes an application production-ready.

Continue learning

Previous: Transaction Continuity.

Return to the Fastify Overview or Framework Tracks. NestJS is the next planned framework integration and remains separate from this track.