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Senior Frontend Developer with 8+ years of experience building and optimizing scalable web applications. Expert in React, TypeScript, and modern build tooling, leveraging AI-driven workflows (Cursor, Claude) to accelerate delivery, refactor complex codebases, and maintain high code quality. Experienced improving deployment pipelines, accessibility, SEO, and performance (Core Web Vitals). Skilled in integrating privacy/compliance solutions (GDPR), mentoring teams, and continuously enhancing internal tooling and developer experience across projects.…Senior Frontend Developer with 8+ years of experience building and optimizing scalable web applications. Expert in React, TypeScript, and modern build tooling, leveraging AI-driven workflows (Cursor, Claude) to accelerate delivery, refactor complex codebases, and maintain high code quality. Experienced improving deployment pipelines, accessibility, SEO, and performance (Core Web Vitals). Skilled in integrating privacy/compliance solutions (GDPR), mentoring teams, and continuously enhancing internal tooling and developer experience across projects.

Sarmun Bustillo Arrechea

Front-End Developer, Web Developer, Software Engineer, +2

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Senior Frontend Developer with 8+ years of experience building and optimizing scalable web applications. Expert in React, TypeScript, and modern build tooling, leveraging AI-driven workflows (Cursor, Claude) to accelerate delivery, refactor complex codebases, and maintain high code quality. Experienced improving deployment pipelines, accessibility, SEO, and performance (Core Web Vitals). Skilled in integrating privacy/compliance solutions (GDPR), mentoring teams, and continuously enhancing internal tooling and developer experience across projects.…Senior Frontend Developer with 8+ years of experience building and optimizing scalable web applications. Expert in React, TypeScript, and modern build tooling, leveraging AI-driven workflows (Cursor, Claude) to accelerate delivery, refactor complex codebases, and maintain high code quality. Experienced improving deployment pipelines, accessibility, SEO, and performance (Core Web Vitals). Skilled in integrating privacy/compliance solutions (GDPR), mentoring teams, and continuously enhancing internal tooling and developer experience across projects.

Available to hire

Senior Frontend Developer with 8+ years of experience building and optimizing scalable web applications. Expert in React, TypeScript, and modern build tooling, leveraging AI-driven workflows (Cursor, Claude) to accelerate delivery, refactor complex codebases, and maintain high code quality.

Experienced improving deployment pipelines, accessibility, SEO, and performance (Core Web Vitals). Skilled in integrating privacy/compliance solutions (GDPR), mentoring teams, and continuously enhancing internal tooling and developer experience across projects.

Skills

Experience Level

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Intermediate

Language

Spanish; Castilian

Fluent

English

Advanced

German

Advanced

Work Experience

Senior Frontend Developer at F7 Media GmbH

March 1, 2024 - Present

Accelerated development and deployment pipelines by 3–10× by migrating to Vite and building custom plugins for internal needs, replacing legacy build tools. Integrated AI-assisted workflows (Cursor, Claude) into daily development to speed up boilerplate setup, component refactoring, and code documentation cycles. Used AI tools to rapidly prototype client concepts, reducing turnaround time for simple CMS implementations and streamlining debugging. Maintained and continuously improved a custom Vite-based build system to ensure compatibility across projects, streamline onboarding, and improve developer experience. Implemented cookie consent and tracking management solutions to comply with EU privacy regulations (GDPR). Optimized advanced Web Core Vitals metrics and accessibility compliance, driving measurable improvements in UX and SEO. Mentored junior and mid-level developers through technical guidance, code reviews, and onboarding support.

Frontend Developer at F7 Media GmbH

September 1, 2021 - February 28, 2024

Collaborated cross-functionally with design and backend teams to deliver high-quality, scalable web applications. Contributed to technology upgrade initiatives, including migration to SPA architectures and headless CMS. Proactively optimized Web Core Vitals, accessibility standards, and SEO to improve site performance and search rankings. Maintained and enhanced custom frontend libraries and build tooling to streamline development processes.

Junior Frontend Developer at F7 Media GmbH

March 1, 2020 - August 31, 2021

Developed and maintained client websites and web applications focused on functional, responsive user interfaces. Collaborated with designers to deliver pixel-perfect layouts and maintain brand consistency. Participated in code reviews and followed best practices for clean, maintainable code. Implemented interactive UI elements and animations to increase user engagement.

Freelancer (Frontend/Web Developer)

August 1, 2019 - Present

Built and managed custom websites and web applications for a range of clients, with strong focus on performance and user experience. Delivered tailored CMS integrations and templates enabling clients to manage content efficiently and independently. Provided long-term technical support, updates, and iterative improvements for live projects based on client needs. Advised clients on modern frontend development best practices, tooling, and performance strategy. Designed and implemented custom responsive layouts aligned with client brand identities, enhancing visual consistency. Boosted SEO performance and accessibility compliance to help clients reach wider audiences and meet industry standards.