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I'm Fred Zerpa, a Full Stack Software Engineer based in Madrid, Spain. I build scalable web applications using Python, JavaScript, React and Node.js, with a strong focus on backend services, database design with SQL and MongoDB, and cloud deployments on AWS and Docker. I enjoy turning complex requirements into reliable, maintainable solutions and collaborating across frontend and backend teams. I thrive in agile environments, communicate clearly, and continuously seek to improve code quality, performance, and user experience. I speak English (C1/C2) and Spanish, and I'm always eager to learn and embrace new challenges.…I'm Fred Zerpa, a Full Stack Software Engineer based in Madrid, Spain. I build scalable web applications using Python, JavaScript, React and Node.js, with a strong focus on backend services, database design with SQL and MongoDB, and cloud deployments on AWS and Docker. I enjoy turning complex requirements into reliable, maintainable solutions and collaborating across frontend and backend teams. I thrive in agile environments, communicate clearly, and continuously seek to improve code quality, performance, and user experience. I speak English (C1/C2) and Spanish, and I'm always eager to learn and embrace new challenges.

Fred Zerpa

Full Stack Developer, Developer, Back-End Developer, +5

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I'm Fred Zerpa, a Full Stack Software Engineer based in Madrid, Spain. I build scalable web applications using Python, JavaScript, React and Node.js, with a strong focus on backend services, database design with SQL and MongoDB, and cloud deployments on AWS and Docker. I enjoy turning complex requirements into reliable, maintainable solutions and collaborating across frontend and backend teams. I thrive in agile environments, communicate clearly, and continuously seek to improve code quality, performance, and user experience. I speak English (C1/C2) and Spanish, and I'm always eager to learn and embrace new challenges.…I'm Fred Zerpa, a Full Stack Software Engineer based in Madrid, Spain. I build scalable web applications using Python, JavaScript, React and Node.js, with a strong focus on backend services, database design with SQL and MongoDB, and cloud deployments on AWS and Docker. I enjoy turning complex requirements into reliable, maintainable solutions and collaborating across frontend and backend teams. I thrive in agile environments, communicate clearly, and continuously seek to improve code quality, performance, and user experience. I speak English (C1/C2) and Spanish, and I'm always eager to learn and embrace new challenges.

Available to hire

I’m Fred Zerpa, a Full Stack Software Engineer based in Madrid, Spain. I build scalable web applications using Python, JavaScript, React and Node.js, with a strong focus on backend services, database design with SQL and MongoDB, and cloud deployments on AWS and Docker. I enjoy turning complex requirements into reliable, maintainable solutions and collaborating across frontend and backend teams.

I thrive in agile environments, communicate clearly, and continuously seek to improve code quality, performance, and user experience. I speak English (C1/C2) and Spanish, and I’m always eager to learn and embrace new challenges.

Skills

Experience Level

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Intermediate

Intermediate

Language

English

Fluent

Spanish; Castilian

Fluent

Work Experience

Software Developer at VA Locator

November 30, 2024 - July 10, 2025

Developed robust RESTful APIs using Express.js/Node.js and implemented CI/CD pipelines with Jenkins, boosting data collection and analysis efficiency by more than 50%. Designed dynamic user interfaces with ReactJS, integrating Redux or Context API, React-Router, and containerized front-end and back-end applications with Docker for improved scalability. Leveraged AWS services (S3, EC2, Lambda) for enhanced cloud storage, computing, and serverless operations, and employed agile methodologies (JIRA) to achieve 100% automated testing coverage that significantly reduced production issues. Implemented automated testing with Jest, React Testing Library, and Supertest to ensure high code quality and minimize production issues.

Software Developer at iWorker

November 30, 2024 - July 10, 2025

Optimized SQL queries for better performance and developed cloud-integrated RESTful APIs using AWS services such as Amazon RDS and AWS Lambda, improving system performance by 18%. Built interactive front-end applications with Next.js, incorporating caching technologies (Redis & SWR) to reduce load times by 25% and enhance SEO performance. Managed version control using Git (GitLab/Bitbucket) and streamlined development processes via GitHub Actions, contributing to a 95% on-time project delivery rate.

Operations Engineer at Unidad Educativa El Ángel

September 30, 2023 - July 10, 2025

Designed and implemented a cloud-based API using the MERN stack (MongoDB, Express.js, React.js, Node.js), integrating Material-UI (MUI) as the user interface, automating data collection by 33%. Implemented containerized services with Docker and Kubernetes, enhancing deployment efficiency and scalability. Designed a disaster recovery plan using Node.js and MongoDB to ensure system uptime and data integrity.

Secure Software Developer at GuardedBox

January 1, 2025 - January 1, 2025

Worked primarily on frontend development using React, focusing on UI improvements, usability and maintainable components. Collaborated with backend and security teams to integrate frontend features with SQL-based data sources. Improved internal tools by refactoring frontend logic and enhancing data presentation. Participated in Scrum-based workflows, contributing through task tracking, collaboration and documentation.

Software Developer at VA Locator

January 1, 2022 - January 1, 2024

Developed full stack web applications using React (frontend) and Node.js / Python (backend). Designed, implemented and consumed custom REST APIs using FastAPI. Automated backend workflows and data processing using Python and JavaScript, reducing repetitive manual tasks and improving consistency. Designed and optimized SQL queries and worked with MongoDB, improving data retrieval performance and reporting efficiency. Deployed and supported services in AWS (S3, EC2, Lambda), contributing to scalable and reliable cloud-based solutions. Worked in Scrum-based agile teams, participating in sprint planning and task tracking using Jira, ensuring on-time delivery and continuous improvement.

Customer Support at Digilink

January 1, 2018 - January 1, 2019

Managed 50+ daily support calls via phone, live chat and emails using VoIP, Zendesk, Gmail, and Intercom, achieving a 90% customer satisfaction rate. Documented customer feedback and KPIs in Google Sheets, sharing daily reports via Slack to improve internal visibility. Organized scheduling and follow-ups using their own Scheduling System.

Operations Engineer at Unidad Educativa El Ángel

January 1, 2020 - December 31, 2021

Designed and implemented a cloud-based API using MERN stack (MongoDB, Express.js, React.js, Node.js), integrating Material-UI (MUI) as the user interface, automating data collection by 33%. Implemented containerized services with Docker and Kubernetes, enhancing deployment efficiency and scalability. Provided Level 3 (L3) technical support for complex system incidents, documented troubleshooting procedures and configurations to reduce escalations.