SocialHub: six social networks behind one interface, testable without a single real account

We put every network behind one interface, SocialChannelProvider, and wrote each of the six twice: a live implementation that speaks the real API, and a simulator that behaves like it. In simulated mode the networks perform the OAuth handshake, accept or reject posts by the real per-network rules, fail a configurable share of publishes so the retry path is exercised, and return comments and metrics over time. Switching a workspace from simulated to live is configuration, not a code change, and the application refuses to start in live mode without its encryption key.

The platform is a Java 21 and Spring Boot 3.3 API with PostgreSQL 16 and Redis, and a Vue 3 and TypeScript frontend. It was built in six phases, each ending in a working product: accounts, workspaces and roles; channel connection, media library and a composer that adapts one post per network; scheduling with a drag-and-drop calendar, approvals, campaigns and automatic retry with backoff; a unified inbox and an analytics dashboard fed by scheduled metric collection; eight Claude-powered writing and reply features behind a per-workspace spend guard and a brand voice; and finally demo seed data and a full verification pass.

AI is optional by design. Without an API key the AI controls disable themselves with a reason and the rest of the product works unchanged. The one feature allowed to write by itself, Autopilot, is held narrow: each autopilot is switched on explicitly, and what it writes waits in the ordinary approval queue by default.

We are plain about the limit of this approach: the live implementations are built to each network's documented API but have not yet been verified against the real networks. That verification is the remaining step before launch, which is why SocialHub is listed as coming soon.