Hydro plugin fundamentals including entry patterns (function-style apply, class-style Service, and mixed mode), import conventions, plugin package structure, database access (ctx.db and deprecated db), management scripts (ctx.addScript), and a complete minimal working example.
Hydro plugin service APIs including SettingService (plugin configuration), StorageService/StorageModel (file storage), TaskModel (background job queue), ScheduleModel (delayed task execution), and OAuth provider registration for third-party login.
Comprehensive guide to HTTP request handling and WebSocket connections in Hydro plugins. Covers route registration, handler lifecycle, parameter decorators, response building, operations, the @requireSudo security decorator, WebSocket handlers, and inheritance patterns.
Complete reference to Hydro's event system including event API (ctx.on/emit/broadcast), cluster-safe broadcasting, 60+ event types, resource cleanup (ctx.effect), timed tasks (ctx.interval), and replaceable modules (ctx.provideModule).
Guide to frontend plugin development including page registration (NamedPage, AutoloadPage), Nunjucks templates, UI injection, and internationalization (i18n). Build interactive frontend features for Hydro plugins.