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Johan Villalpando

@johanvillalpando

Message

Backend-focused Java/Spring Boot engineer building secure, scalable AWS services.

Mexico

Message

What I'm looking for

I’m looking for a backend-focused team where I can build secure Java/Spring Boot services on AWS, own REST API development, and deliver in Agile (Scrum/Kanban) with CI/CD-driven quality and reliability.

I’m a backend-focused Software Engineer who builds and deploys scalable applications with Java (Spring Boot) and PostgreSQL. I design REST APIs, implement secure authentication/authorization (JWT/RBAC), and deliver production services on AWS (EC2, RDS) with strong clean-code and microservices practices.

From freelancing to internships, I’ve shipped real outcomes: reducing administrative workload by ~60% for an inventory/payroll/scheduling system, leading a full rebuild of a university website to improve mobile usability for 3,000+ users, and deploying a Spring Boot 3 payment-processing microservice to AWS with improved reliability via centralized exception handling. I’m also actively building a Java 21 e-commerce & POS ecosystem on AWS with Swagger-documented APIs and CI/CD using GitHub Actions, while continuously optimizing performance and adding new features.

Experience

Work history, roles, and key accomplishments

Current

E-Commerce & POS Backend

Current

Personal Project

Dec 2025 - Present (4 months)

Designed a Java 21 / Spring Boot backend for an e-commerce and POS system, replacing a legacy SQLite-based architecture. Implemented Spring Security JWT/RBAC authorization, deployed on AWS (EC2 + RDS PostgreSQL), and automated CI/CD with GitHub Actions to reduce manual deployment time.

Java 21+Spring Boot Spring Security AWS EC2 AWS RDS Unit Testing Performance Optimization

Freelance Full-Stack Dev

Independent

Mar 2025 - Jul 2025 (4 months)

Built and delivered a Laravel + MySQL system for inventory, payroll, and scheduling, reducing administrative workload by ~60%. Developed a booking and payments foundation for a beauty salon and managed multiple client projects independently using Kanban to maintain on-time delivery.

Laravel MySQL Scheduling Payments Integration Kanban Version Control

Web Developer Intern

Universidad Tecnológica El Retoño

Jan 2025 - Jul 2025 (6 months)

Led an end-to-end rebuild of the official university website using a Kanban workflow, improving mobile usability for 3,000+ students and staff. Implemented fully responsive layouts and reduced reported UI bugs through iterative QA.

Responsive Web Design Kanban & QA HTML CSS JavaScript Usability Version Control

Java Backend Intern

Private Sector Company

Apr 2025 - Jun 2025 (2 months)

Developed and deployed a Spring Boot 3 microservice for payment processing with 6 REST endpoints (create, retrieve, capture orders). Deployed on AWS EC2, integrated external APIs, and improved reliability by reducing unhandled errors via centralized exception handling.

Java Spring Boot Microservices REST APIs AWS EC2 API Integration