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I am William D. Sotto, a passionate Full Stack Developer based in Barcelona. I enjoy building scalable web applications using modern front-end frameworks like React and Angular, paired with robust back-end services in Node.js and Java. I strive to apply SOLID and DRY principles, deliver responsive and accessible user experiences, and optimize performance across the stack. I thrive in agile teams, working on academic and professional projects with a focus on clean architectures, automated processes, and thorough documentation to ensure maintainability and scalability.…I am William D. Sotto, a passionate Full Stack Developer based in Barcelona. I enjoy building scalable web applications using modern front-end frameworks like React and Angular, paired with robust back-end services in Node.js and Java. I strive to apply SOLID and DRY principles, deliver responsive and accessible user experiences, and optimize performance across the stack. I thrive in agile teams, working on academic and professional projects with a focus on clean architectures, automated processes, and thorough documentation to ensure maintainability and scalability.

William D. Sotto

Full Stack Developer, Back-End Developer, Front-End Developer, +2

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I am William D. Sotto, a passionate Full Stack Developer based in Barcelona. I enjoy building scalable web applications using modern front-end frameworks like React and Angular, paired with robust back-end services in Node.js and Java. I strive to apply SOLID and DRY principles, deliver responsive and accessible user experiences, and optimize performance across the stack. I thrive in agile teams, working on academic and professional projects with a focus on clean architectures, automated processes, and thorough documentation to ensure maintainability and scalability.…I am William D. Sotto, a passionate Full Stack Developer based in Barcelona. I enjoy building scalable web applications using modern front-end frameworks like React and Angular, paired with robust back-end services in Node.js and Java. I strive to apply SOLID and DRY principles, deliver responsive and accessible user experiences, and optimize performance across the stack. I thrive in agile teams, working on academic and professional projects with a focus on clean architectures, automated processes, and thorough documentation to ensure maintainability and scalability.

Available to hire

I am William D. Sotto, a passionate Full Stack Developer based in Barcelona. I enjoy building scalable web applications using modern front-end frameworks like React and Angular, paired with robust back-end services in Node.js and Java. I strive to apply SOLID and DRY principles, deliver responsive and accessible user experiences, and optimize performance across the stack.

I thrive in agile teams, working on academic and professional projects with a focus on clean architectures, automated processes, and thorough documentation to ensure maintainability and scalability.

Skills

Experience Level

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Intermediate

Intermediate

Intermediate

Language

Spanish; Castilian

Fluent

Catalan; Valencian

Fluent

English

Fluent

Work Experience

Full Stack Developer (Academic Project) at Universitat de Barcelona

January 1, 2025 - September 10, 2025

Desarrollo de una aplicación web full stack para gestión de presupuestos de reformas (Budget Management Web App). Tech stack: Next.js, FastAPI, Tailwind CSS y MySQL; desarrollo multilingüe con UI administrativa.

Backend Developer at Grupo Hotusa

January 1, 2025 - September 10, 2025

Desarrollo de servicios REST con Java y Node.js, integración con Oracle, FTP y manejo de errores; diseño de API robusta y trazabilidad de fallos.

Frontend Developer (Internship) at Grupo Hotusa

January 1, 2025 - September 10, 2025

Refactorización de componentes Angular 14→18, aplicando principios SOLID y DRY; optimización de rendimiento; manejo de formularios dinámicos; mejora de la experiencia de usuario y accesibilidad.

Proyecto Final de Grado en Producción de Proyectos at Universitat de Barcelona

January 1, 2025 - Present

Budget Management Web App for Renovation Projects como proyecto de fin de grado, con Next.js, FastAPI, Tailwind CSS y MySQL. Diseño y desarrollo de una solución full stack para digitalizar la gestión de presupuestos de reformas.

Full Stack Developer (Proyecto universitario) at Universitat de Barcelona

January 1, 2025 - Present

Budget Management Web App for Renovation Projects. Desarrollo de una aplicación web full stack multilingüe para gestión de presupuestos de renovación. Stack: Next.js, FastAPI, Tailwind CSS, MySQL. Arquitectura modular basada en roles y paneles. Exportación a PDF/CSV, gestión de gastos e informes, y panel de administración. Despliegue y documentación orientada a mantenibilidad.

Full-Stack Developer (Project) at Universitat de Barcelona

January 1, 2025 - Present

Budget Management Web App for Renovation Projects. Built a full-stack web app to manage budgets; Next.js, FastAPI, Tailwind CSS, MySQL. Admin dashboards with role-based access, expense tracking, and dynamic reports. Export PDFs/CSVs; multi-language UI; pagination and accessibility improvements. Documented code for maintainability.

Full-Stack Developer - Final Degree Project at Universitat de Barcelona

January 1, 2025 - September 7, 2025

Developed a full-stack, multilingual web app for renovation-budget management. Tech stack included Next.js, FastAPI, Tailwind CSS; features included admin dashboards, expense tracking, PDF exports, and external API integration; modular, scalable architecture with documentation.

Full Stack Developer at Universitat de Barcelona

January 1, 2025 - Present

Developed a full-stack, multilingual web application to manage construction and renovation budgets with a modular, role-based architecture and responsive UI. The platform allows administrators to assign tasks, register materials and expenses, and generate financial reports. Key features include differentiated user roles (Admin, Worker, Client) with role-based dashboards, real-time cost tracking with interactive charts, project-based downloadable PDF/CSV reports, deployed with the frontend on Vercel and backend on Railway.

Back-End Developer (Java + Oracle + FTP + REST API) at Grupo Hotusa

January 1, 2024 - Present

Designed and developed a fully automated system integrating an external API for currency operations. Processed and transformed CSV files via FTP into objects sent to the API, persisting data in Oracle with custom tables and error traceability. Applied clean architecture based on package separation and implemented CRON jobs for automatic daily execution. Integrated Neo4j for graph-based tracking of data flows and relationships. Achievements included full automation of financial operations data loading, detailed error logging, scalable architecture for future API integrations, and utilizing Neo4j to map complex financial entity relationships.

Full Stack Developer (Internship) at Grupo Hotusa

January 1, 2024 - Present

Refactored Angular components from version 14 to version 18 applying SOLID and DRY principles, leading to performance improvements of over 30% load speed. Implemented REST endpoints for complex forms using Node.js and Express. Validated and improved dynamic forms including error handling between frontend and backend, enhanced user experience through responsive design, accessibility, and pagination. Participated in SCRUM methodology with weekly sprints, daily meetings, and retrospectives while managing tasks on an internal platform with time tracking and tutor validation.