WooCommerce REST APIHow WCPOS reads your store through the WooCommerce REST API, how to see the data the POS holds on the JSON tab, and why plugins that change prices or products on the fly don't reach the till.
ArchitectureHow WCPOS is built: the plugin on your WordPress site, the POS app on each till, the database the till sells from, how the two stay in step, and how checkout records payments.
Sync EngineDeveloper reference for the WCPOS 2.x sync engine: one database per store and cashier, background lanes, the change check, coverage, the write queue, one live browser tab and local storage.
Sync PerformanceThe numbers behind Store health's Performance tab: what each sync setting costs your server, how the POS backs off when your server struggles, and how the till stays responsive.
Role Endpoint AccessDeveloper reference: which WCPOS REST endpoints the administrator, shop_manager and cashier roles can reach, how a refused request is answered, and how to tell a role problem from a sign-in problem.
Discount RecordsDeveloper reference for how WCPOS records a price changed at the till and an Add Discount line on the WooCommerce order, how both interact with coupons, and the filter and receipt fields that expose them.
Search MatchingWhich fields each search box in WCPOS looks at, how the words you type are matched, phone numbers, and the wcpos_search_fields filter for a store's own fields.
Gateway TemplateBuild your own POS-only payment gateway for WCPOS from the gateway template: one PHP file, a setup script and automatic GitHub releases.
Gateway Checkout FieldsFor gateway developers: two filters let the POS draw your gateway's checkout fields on the tender pane with its own controls, then run your gateway's process_payment() with what the cashier enters.