Freelancer profile translated to English.
Back to original languageAbout Rubén
I build digital products that deliver results: SaaS with payments and subscriptions, cross-platform mobile apps, high-converting landing pages, and AI-powered automations.
I work with Next.js, Flutter, and Firebase/Supabase, and integrate LLM models (GPT, Claude, Gemini) to create intelligent experiences: chatbots, autonomous agents, content generation, and AI pipelines.
I don't just deliver code: I get involved in the business, care about user experience, and ensure the product reaches its first customers. I've founded and launched my own SaaS products, so I understand the journey from zero to production. Additionally, I have experience leading teams at product companies like Holaluz and deploying code to production at IBEX 35 companies like Bankinter and Telefónica.
I can help you with:
- Rapid MVP for SaaS or mobile app
- Integrating LLMs and AI agents into your product
- Automations that save time and money
- SEO-optimized websites and landing pages with Next.js
If you have an idea and want to move fast, let's talk.
Spanish
Native or bilingual
English
Fluent
Remote only
Primarily works remotely
Experience
- Momentum CoachFounderSOFTWARE PUBLISHINGSeptember 2025 - Today (11 months)Madrid, SpainPowerlifting application with artificial intelligence developed in Flutter and Firebase. I designed the full-stack architecture, the LLM coaching flows, the training plan management, and monetization with subscriptions. I also cover product analytics, iOS/Android releases, observability, and internal automations to iterate quickly from real product data.
- SF StudioCo-FounderSOFTWARE PUBLISHINGFebruary 2025 - Today (1 year and 6 months)Madrid, SpainWeb and Custom App Development Studio. Development of mobile applications with Flutter, websites with Next.js, and customized digital solutions for clients. Specialization in cloud architecture, API integrations, and production deployment.
- Holaluz.comTeam Lead & Senior Software EngineerApril 2023 - January 2025 (1 year and 9 months)As a Senior Engineer, I was responsible for maintaining, evolving, and creating some of the company's core applications and services. This included high-concurrency REST/Microservices and asynchronous messaging with Kotlin/PHP + SNS/SQS/Kafka in a DDD architecture, as well as dealing with very legacy Java 1.8 code and batch processes in a rather unfriendly ERP.
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Education
- Introduction to Objective C & iOS Eclipse IDE for Beginners: Increase Your Java Productivity Project management with Agile methodologies and Lean approaches. JUnit Tutorial for BeginnersIntroducción a Objective C & iOS Eclipse IDE for Beginners: Increase Your Java Productivity Gestión de proyectos con metodologías Ágiles y enfoques Lean. JUnit Tutorial for Beginners
- University Expert in DevOps & Cloud, Computer Technology/Computer Systems TechnologyUNIR - The Online University2022Experto Universitario en DevOps & Cloud, Tecnología informática/Tecnología de sistemas informáticos