# API Design · Tech watch

[Canonical source](<https://sebastien.rigaux.be/en/tech-watch/tags/api-design>)

Designing API contracts, errors and behavior for consumers.

## [ActivityPub: a federated protocol with formal change rules](<https://sebastien.rigaux.be/en/tech-watch/links/activitypub-a-federated-protocol-with-formal-change-rules>)

The W3C repository presents ActivityPub, a decentralized social networking protocol that combines a client-to-server API with a federated server-to-server API. Built on the ActivityStreams 2.0 JSON-LD format, it supports extensible activity descriptions and different kinds of social applications.

The repository also explains how to evolve a published recommendation: clarifications belong in the Primer, corrections follow an errata process, and breaking changes require a new working group. That formal governance reflects the deployment cost of changing a protocol used by many independently operated servers.

2026-10-29 · [Markdown](<https://sebastien.rigaux.be/en/tech-watch/links/activitypub-a-federated-protocol-with-formal-change-rules.md>) · [Original resource](<https://github.com/w3c/activitypub>)

## [AT Protocol: shared lexicons for publishing and indexing](<https://sebastien.rigaux.be/en/tech-watch/links/at-protocol-shared-lexicons-for-publishing-and-indexing>)

Standard.site proposes shared lexicons for publishing platforms on AT Protocol. The goal is to give indexers and tools a common schema while making content easier to discover and move between hosts.

The standard describes metadata for publications, documents, and subscriptions without prescribing a content format. Each platform can choose which lexicons to implement. Verification uses a `/.well-known/site.standard.publication` route to link a domain to its publication, and an HTML tag to associate a document with its AT-URI.

2026-10-29 · [Markdown](<https://sebastien.rigaux.be/en/tech-watch/links/at-protocol-shared-lexicons-for-publishing-and-indexing.md>) · [Original resource](<https://standard.site/>)

## [Next Zod Route: type and validate Route Handlers](<https://sebastien.rigaux.be/en/tech-watch/links/next-zod-route-type-and-validate-route-handlers>)

Next Zod Route validates parameters, query strings and request bodies with Zod. Middleware and response handling help centralize conventions across Next.js API routes.

2025-02-13 · [Markdown](<https://sebastien.rigaux.be/en/tech-watch/links/next-zod-route-type-and-validate-route-handlers.md>) · [Original resource](<https://github.com/Melvynx/next-zod-route>)