I am a frontend developer with a strong focus on building scalable, responsive, high-performance web applications. I specialize in the React ecosystem (React, Next.js, JavaScript/TypeScript) and modern styling frameworks. Perseverance is my main quality. I translate business requirements into functional, user-friendly interfaces and collaborate closely with teams to ensure high-quality code and optimal performance. In my spare time, I enjoy exploring AI-driven automation and keeping up with new technologies.

Juan Castilla Mariscal

I am a frontend developer with a strong focus on building scalable, responsive, high-performance web applications. I specialize in the React ecosystem (React, Next.js, JavaScript/TypeScript) and modern styling frameworks. Perseverance is my main quality. I translate business requirements into functional, user-friendly interfaces and collaborate closely with teams to ensure high-quality code and optimal performance. In my spare time, I enjoy exploring AI-driven automation and keeping up with new technologies.

Available to hire

I am a frontend developer with a strong focus on building scalable, responsive, high-performance web applications. I specialize in the React ecosystem (React, Next.js, JavaScript/TypeScript) and modern styling frameworks. Perseverance is my main quality. I translate business requirements into functional, user-friendly interfaces and collaborate closely with teams to ensure high-quality code and optimal performance. In my spare time, I enjoy exploring AI-driven automation and keeping up with new technologies.

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Experience Level

Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Intermediate
Intermediate
Intermediate
Intermediate
Intermediate
Intermediate
Intermediate
Intermediate
Intermediate
Intermediate
Intermediate
Intermediate
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Language

Spanish; Castilian
Fluent
English
Advanced

Work Experience

Freelance Web Developer at Freelance
March 1, 2023 - September 17, 2025
Designing and implementing websites for businesses using WordPress, Shopify and JavaScript; applying marketing strategies to promote services.
Private Teacher at Self-Employed
July 1, 2022 - September 17, 2025
Private programming educator for young learners, helping them build foundational skills.
Frontend Developer at Prodia Consultores S.L
January 1, 2024 - September 17, 2025
Implementation of UX design in websites; CSS/SASS, JavaScript client functionalities; creating Drupal 9 modules; web performance and browser compatibility tests.
Frontend Developer at Almora Soluciones
April 1, 2024 - September 17, 2025
Frontend development work including UX improvements and website development.
Automation/Frontend Developer at Buwic AI Málaga
September 1, 2025 - September 17, 2025
Automation of internal processes in companies with AI and related marketing tasks.
Frontend Developer at Buwic AI Málaga
September 1, 2025 - September 20, 2025
Automating internal business processes with AI using N8N and Make; AI marketing automation; WordPress development; assistant scraping tasks.
WordPress Developer at Marketing (Freelance), Málaga
June 1, 2025 - September 20, 2025
Website development in WordPress; implemented UX design for websites; collaborated with clients to deliver responsive sites.
Frontend Developer at Producia Consultores S.L
January 1, 2024 - September 20, 2025
Implemented UX design in websites; integrated CSS, SASS and JavaScript client functionalities; created modules in Drupal 9.
Web Developer at Freelance
March 1, 2023 - September 20, 2025
Design and development of websites in WordPress, Shopify and JavaScript; marketing strategies to promote services.
Private Tutor at Private Tutor
July 1, 2022 - September 20, 2025
Teaching programming to young people who want to learn to code.
Frontend Developer at Buwic AI Málaga
September 1, 2025 - September 20, 2025
Automating internal business processes with AI using N8N and Make.
WordPress Developer at Marketing
June 1, 2025 - September 20, 2025
Website development in WordPress; Plugins and AI systems automation processes.
Frontend Developer at Almora Soluciones
April 1, 2024 - September 20, 2025
Implemented UX design in websites; CSS/SASS styles and JavaScript client functionalities; Created modules in Drupal 9; Implemented web performance and browser compatibility tests.
Frontend Developer at Prodiga Consultores S.L
January 1, 2024 - September 20, 2025
Implemented UX design in websites; CSS/SASS styles and JavaScript client functionalities; Created modules in Drupal 9; Implemented web performance and browser compatibility tests.
Web Developer at Freelancer
March 1, 2023 - September 20, 2025
Design and implement websites for businesses in WordPress, Shopify and JavaScript. Used marketing strategies to promote services.
Private Tutor at Private Tutor
July 1, 2022 - September 20, 2025
Teaching programming to young people who want to learn.
Frontend Developer at Solbyte
March 1, 2026 - Present
Frontend developer for web applications in React with Next.js.
Lead Frontend Developer at Internal Time-Tracking App (Malaga project)
October 1, 2025 - March 1, 2026
Led frontend development of an internal time-tracking application using React and modern JavaScript, significantly improving user experience and attendance-tracking accuracy.
Frontend Developer at Buwic AI
June 1, 2025 - September 1, 2025
Automating internal business processes with AI using N8N and Make; marketing automation; AI-assisted workflows; WordPress development.
Frontend Developer at Prodia Consultores S.L.
March 1, 2023 - January 1, 2024
Implemented UX design in websites; incorporated CSS, SASS; created modules in Drupal 9.
Web Developer at Freelancer
August 1, 2018 - March 1, 2023
Design and implement websites for businesses in WordPress, Shopify and JavaScript; plugins and AI automation processes.
Private Tutor
April 1, 2021 - July 1, 2022
Teaching programming to young people who want to learn to code.
Frontend Developer at Freelancer
August 1, 2018 - March 1, 2023
Design and implement websites for businesses using WordPress, Shopify, and JavaScript. Applied marketing strategies to promote services.
Frontend Developer at Prodia Consultores S.L
March 1, 2023 - January 1, 2024
Implemented UX design in websites; incorporated CSS/SASS styles and JavaScript client functionalities; created modules in Drupal 9; implemented web performance and browser compatibility tests.
Frontend Developer at Solbyte
October 1, 2025 - March 1, 2026
Lead the frontend development of an internal time-tracking application using React and modern JavaScript, significantly improving the user experience and the accuracy of attendance tracking.
Frontend Developer at Freelancer
March 1, 2026 - Present
Freelance frontend development for web apps in React with Next.js; translation of business requirements into functional interfaces and collaboration with teams to deliver high-quality code.

Education

React MERN Hooks Course at Udemy
May 1, 2023 - January 1, 2024
ASIR (Administración de Sistemas Informáticos en Red) at IES Oretania
September 1, 2021 - March 1, 2023
React MERN Hooks course at Udemy
May 1, 2023 - January 1, 2024
React MERN Hooks +66h at Udemy
May 1, 2023 - January 1, 2024
Web App Development at Cenec Málaga
September 1, 2021 - March 1, 2023
React MERN Hooks course (66h) at Udemy
May 1, 2023 - January 1, 2024
Course at Udemy - React MERN + Hooks
May 1, 2023 - January 1, 2024
Web App Development (DAW) at Desarrollo de Aplicaciones Web (DAW) – Curso
September 1, 2021 - March 1, 2023

Qualifications

ASIR Certification
September 1, 2021 - March 1, 2023
React MERN Hooks Course
May 1, 2023 - January 1, 2024
React MERN Hooks course
May 1, 2023 - January 1, 2024
Testing with Jest and Cypress
September 1, 2021 - March 1, 2023
React MERN Hooks course (66h)
May 1, 2023 - January 1, 2024

Industry Experience

Software & Internet, Professional Services, Media & Entertainment, Education, Retail, Other