Eight disciplines make up the archive. Each one carries a recurring cast of problems, and each archive is written so it can be read front to back as a short course in that area.
Hooks, the database layer, cron, and the parts of core that decide how your plugin behaves under load.
Order lifecycle, checkout, HPOS, sessions and the post-purchase communication layer.
Query budgets, object caching, Core Web Vitals and measuring before you optimise.
REST design, webhooks, authentication, idempotency and talking to couriers and ERPs.
Capability checks, nonces, sanitisation, SQL safety and threat modelling for plugins.
Block themes, progressive enhancement, ARIA, and interfaces that work without JavaScript.
Local environments, static analysis, CI, release packaging and debugging technique.
Server configuration, caching layers, queues, observability and deployment practice.