payflow

PayFlow is a complete business suite for small and medium companies, part of the Sparken ecosystem: a point-of-sale system with electronic invoicing connected to Ecuador's tax authority (SRI), inventory management with a dedicated mobile app for stock audits, payroll control, and a marketing module for sending campaigns and promotions to customers. It also includes PayFlow Market, an e-market where businesses registered as wholesale distributors can sell inside the platform, taking delivery or pickup orders. I build and maintain it end to end: React and Next.js front ends over Spring Boot microservices with PostgreSQL, Redis and Kafka, on AWS managed with Terraform.

Small and medium companies in Ecuador usually run sales, invoicing, stock and payroll in disconnected tools, while legal compliance adds pressure of its own: every electronic invoice must be reported to the SRI. PayFlow answers with one integrated platform. The front end is built with React and Next.js on TypeScript, TailwindCSS, Redux Toolkit and TanStack Query, over Java microservices with Spring Boot, where PostgreSQL stores the records, Redis accelerates reads and Kafka carries the events that keep point of sale, inventory and reporting in sync.

David Gavilanez, team lead and Senior Full-Stack Developer at Sparken, builds and maintains the product end to end and mentors the team behind it. Quality is enforced in the pipeline, not negotiated afterwards: SonarQube gates with Cypress, Testing Library and Jest run on every release, and the interface is assembled from the company's own TailwindCSS component library, documented in Storybook. The suite keeps growing around its merchants, from the PayFlow Market wholesale channel to the marketing module that pushes their promotions to customers.