Requirements analysis, direct communication with clients to understand project needs, implement new features and fix bugs, perform API integration, external database management, backend workflow scheduling, UI and UX knowledge, following best development practices, project documentation, creation of JavaScript charts with chart.js, integration with online payment platforms like Juno, MercadoPago, Asaas, and Stripe, social login authentication with Google and Facebook, database structure planning, and project execution from start to finish.