Should new UK TypeScript projects use tRPC or REST internally?

For internal full-stack TypeScript APIs (Next.js frontend → Node.js backend, same codebase): tRPC is the correct choice. Benefits: (1) no OpenAPI schema to maintain, (2) TypeScript types shared automatically — backend changes instantly reflected in frontend type errors, (3) Zod input validation generates tRPC input schema automatically, (4) React Query integration (tRPC client uses React Query — caching, loading states, refetching all handled). When to use REST internally instead of tRPC: (1) non-TypeScript clients need to call the internal API, (2) the internal API will eventually become a public external API (start REST, add OpenAPI from day 1), (3) team prefers explicit API contracts over implicit TypeScript types.

What is the UK regulatory position on tRPC for FCA-regulated APIs?

tRPC for FCA-regulated external APIs: not appropriate. FCA COBS machine-readable product information requirements, NHS FHIR R4 standard, and GDS Service Standard all require REST + OpenAPI 3.0 for external-facing APIs. tRPC does not produce an OpenAPI schema by default (there is a trpc-openapi package — but it adds complexity). FCA Consumer Duty: product information APIs must have OpenAPI 3.0 documentation (machine-readable — FCA regulatory disclosure standard). ClickMasters approach: tRPC for internal type-safe full-stack communication, REST + OpenAPI for any API that faces external consumers (TPPs, NHS systems, GDS, partners). The two can coexist in the same codebase.

Trpc Vs Rest Vs Graphql Uk 2026

tRPC vs REST vs GraphQL — UK TypeScript Full-Stack APIs (2026)

Updated: February 20269 min read

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Direct Answer

REST with OpenAPI 3.0 remains the UK standard for external APIs (FCA COBS, NHS FHIR R4, GDS Service Standard all mandate REST + OpenAPI). tRPC is ClickMasters' default for internal TypeScript full-stack APIs (Next.js App Router + Node.js backend) — end-to-end type safety without schema duplication, zero code generation. GraphQL is right for BFF (Backend For Frontend) aggregation layers where multiple clients need different data shapes. UK API design choice must balance regulated sector compliance requirements (REST mandatory for FCA/NHS/GDS external APIs) with developer productivity (tRPC wins internally).

Factor	REST + OpenAPI 3.0	tRPC	GraphQL
FCA COBS / NHS FHIR R4 / GDS	✅ Required — OpenAPI 3.0 is the regulatory standard	Internal only	Not mandated
End-to-end TypeScript type safety	Via code generation (openapi-typescript)	✅ Native — shared types, zero codegen	Via codegen (graphql-codegen)
UK GDPR data minimisation	OpenAPI select fields — explicit schema	✅ zod schemas — precise input/output validation	GraphQL field selection
Developer productivity	Good — but OpenAPI → client types require codegen	✅ Best — instant type safety, no build step	Good — but resolver boilerplate heavy
External partner integrations	✅ Universal — any client consumes REST	TypeScript clients only	GraphQL clients only
NHS / FCA audit trail	✅ HTTP access logs — standard	Logged via Express/Fastify middleware	Logged via Apollo plugin
Learning curve (new UK team member)	✅ Low — every developer knows REST	Low if knows TypeScript	Medium — GraphQL concepts
ClickMasters use	✅ All external UK APIs (FCA, NHS, GDS)	All internal full-stack TypeScript APIs	BFF aggregation layers only