Multi-section modular architecture, PDO/MySQLi, session management, file upload handling, form validation, JSON-LD schema injection, OOP patterns, Composer autoloading.
DOM manipulation, async fetch/AJAX, Intersection Observer, CSS animations, modal state machines, UTM parameter extraction, auto-popup timers, drag-and-drop APIs.
Paramiko SSH/SFTP automation, deployment orchestration, server backup scripts, database dump pipelines, log parsing, form submission scrapers, automated QA runners.
Schema design, idempotent migrations, prepared statements, FK cascades, multi-DB management (20 databases), bulk mysqldump, query optimization, bind_param auditing.