A key module in the POS Mobile app focusing on online payment processing. Implemented a middleware layer to bridge Espay’s server-side webhook with the Flutter client in real time. Integrating QRIS to ensure the payment succeeded.
A key module in the POS Mobile app focusing on online payment processing. Implemented a middleware layer to bridge Espay’s server-side webhook with the Flutter client in real time. Integrating QRIS to ensure the payment succeeded.
Built the complete payment flow: request, redirect, callback, and webhook validation.
Developed a secure PHP middleware to receive and verify Espay webhook events.
Integrated real-time payment status updates into the Flutter frontend.
Understand actors, states, validations, and operational exceptions before translating them into screens.
Keep mobile, backend, database, and external-system responsibilities explicit and testable.
Design for loading, failure, retries, edge cases, and maintainability—not only the happy path.