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Carlos J GarciaCJ

Carlos J Garcia

Senior Full Stack Dev | Product & Innovation

126 €/día
Madrid, ES
8-15 años

Tiempo medio de respuesta: 1h

Acerca de Carlos J

I help teams and companies turn ideas, prototypes, or partially built products into reliable, working software.

With 8 years of experience as a Senior Full Stack Developer, and currently working in innovation and venture-building environments at Telefónica Innovación Digital, I am used to operating in contexts where requirements are not always fully defined. I can quickly assess technical feasibility, propose pragmatic solutions, and deliver concrete, production-ready results.

I typically work on:

Full stack development for web applications

Backend services, APIs, and system integrations

Authentication and authorization (OAuth, JWT, API keys)

Improving or stabilizing existing codebases

Prototypes and MVPs that need to evolve into maintainable systems

I value clear scopes, asynchronous communication, and well-defined deliverables. My goal is to minimize overhead while maximizing impact, focusing on clean implementations, clear documentation, and predictable outcomes.

I am a good fit if you:

  • Have a specific technical problem to solve
  • Need help validating or implementing a solution
  • Want an experienced developer who can work autonomously
  • Prefer efficient collaboration with few meetings









I am less suited for open-ended engagements without a defined scope or projects requiring heavy day-to-day coordination.

If your project needs someone who can navigate uncertainty, make sound technical decisions, and deliver efficiently, feel free to reach out.
  • Español

    Bilingüe o nativo

  • Inglés

    Competencia profesional completa

Solo teletrabajo
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Experiencia

  • Telefónica Innovación Digital
    Full Stack Develoiper
    TELECOMUNICACIONES
    abril de 2025 - Hoy (1 año y 2 meses)
    I am a Full Stack Developer working on digital products and technical solutions at Telefónica Innovación Digital, within innovation-driven environments, venture building initiatives, and exploratory technology projects.

    I have contributed to both rapid prototypes and production-ready services, collaborating closely with engineering and product teams in fast-moving contexts. I am comfortable operating in uncertain or exploratory scenarios, assessing technical feasibility, validating approaches, and progressively turning ideas into reliable, production-ready solutions.

    My profile is primarily focused on backend development and system architecture, while maintaining strong frontend skills to deliver end-to-end solutions when needed.

    My experience includes:

    Designing and implementing APIs and backend services

    Integrating third-party services and external APIs

    Authentication and authorization systems

    Backend automation, workers, and internal tools

    Frontend development for web applications

    Dockerized environments and reproducible deployments

    I am used to working with well-defined scopes, asynchronous communication, and clear deliverables, prioritizing practical solutions, concise documentation, and efficient execution.
  • ASZENDIT TECH SL
    Full Stack Develoiper
    octubre de 2023 - abril de 2025 (1 año y 6 meses)
    Madrid, España
    Worked as a Full Stack Developer at Aszendit TECH, collaborating as an external consultant on multiple client projects across different industries. During this period, I was involved in innovation-focused initiatives, including projects delivered in collaboration with Telefónica Innovación Digital, which later led to my current internal role.

    My work covered both exploratory and applied development, contributing to projects related to innovation, emerging technologies, and post-quantum topics, where assessing technical feasibility and validating solutions was a key part of the role.

    In parallel, I also worked as a Full Stack Developer for a renewable energy startup, supporting the development and evolution of their product as an external contributor. This involved building and maintaining web applications end to end, adapting to startup constraints, and delivering practical solutions aligned with business needs.

    Across these projects, I gained experience working in heterogeneous technical environments, collaborating with different teams and stakeholders, and delivering solutions under varying levels of definition and uncertainty, always with a strong focus on maintainable code and real-world applicability.
    Fullstack Innovation Postproducción Cloud Engineer Product Development

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Formación

  • Computer Science
    UPM
    2020

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