Proposal: Static Web With Go-Only Runtime APIs

Source

Task: 20260816-static-frontend-go-api-4f8c2a7d
User confirmation: the frontend must be a static page set and every API must be provided by Go.

Replace ADR-003's retained Next.js SSR responsibility with a stricter runtime boundary:

Next.js is a build tool. Its production output is the static out/ tree.
An unprivileged Nginx workload serves pages and static assets only.
The browser calls same-origin /api, /uploads, and /generated-results; Ingress routes those paths directly to the Go modular monolith.
Go exclusively owns authentication, authorization, Cookie signing and validation, PostgreSQL, billing, providers, storage, Webhooks, health, readiness, and the embedded WorkerLoop.
Client route guards are presentation behavior only and never an authorization boundary.
The Web workload receives no runtime ConfigMap, session Secret, database credential, provider Secret, or internal Go URL.

Clean next build exports every application route as static content.
Static architecture tests fail if Next Route Handlers, Middleware, server page imports, image optimization, or a non-same-origin auth seam return.
The checked-in Go route surface covers every browser request; the single discovered billing response casing defect was corrected and regression tested.
Full Vitest, TypeScript, Go, and ACK assertion suites pass.

Production Web availability is independent of PostgreSQL, Go internal DNS, and session-secret injection; API failures become visible client errors rather than fatal RSC rendering errors.
New business endpoints must be implemented in Go. Reintroducing Next Route Handlers, Middleware authentication, or SSR Cookie access violates the accepted boundary.
Schema creation remains an operator/CI concern until a dedicated migration image is justified; it must not reuse the static Web image.

ADR-003 currently says Next serves SSR and that static export is a future choice.
Canonical current-state and architecture documents still describe the internal Next-to-Go auth bridge, retained Next Route Handlers, a Migration Job artifact, and local Node Worker behavior as part of the supported shape.

No further confirmation is required. The user explicitly selected this pure static frontend and Go-only API architecture in the source task.