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Jesús Leganés-CombarroJL

Jesús Leganés-Combarro

WebRTC, Python & Node.js expert - Fullstack dev

€700/day
Zurich, CH
15+ years

Average response time: 1 hour

About Jesús

Passionate computers engineer and ex-PhD. candidate in Computers Engineering. Proud advocate of Open Source, standards, specifications, and best practices.

With more than 18 years of professional experience, and being involved in Open Source scene and wireless communities since I was 17 years old, I have been working both profesionally or in personal side projects in almost all computer engineering areas, including web development, robotics, operating systems desing, videogames, networking, or drivers programming. My profile is purely technical, with a great interest in hard-to-solve problems, quality of code, performance optimizations, high-edge technologies, and design of clean APIs and architectures focused on minimal designs, modularity and reusability.

I’m fullstack with preference for backend, R&D and academic projects. Thanks to that, I have more than 10 years of experience with Node.js, and I’m also expert in Python and C++ between other languajes, and I’m currently interested on Rust. Regarding mobile apps, I have 5 years of experience with ReactNative.

I have won three times the spanish national Universitary Free Software Championship and been CTO of two start-ups (and co-founder of one of them). Currently I’m working as WebRTC Architect at Dyte and as part-time freelance developer, consultor and auditor. In my spare time I like to read books, go to cinema or travelling, go running or cycling, or work on my own side projects to improve my skills and craft things with cool high-edge technologies.

I have a Licenciature in Computers Engineering, and convalidated It to the equivalent Master in Computers Engineering. My Licenciature (and Master) thesis was NodeOS, a minimal operating system for Node.js based applications, with more than 6000 stargazers on GitHub, winner on the Systems category at the 11th CUSL national championship, and graduated with distinction. My Licenciature thesis director was Prof. Enrique Soriano-Salvador.
  • Spanish

    Native or bilingual

  • English

    Native or bilingual

  • French

    Conversational

  • Arabic

    Basic

Can work on-site
Zurich (up to 50km)

Experience

  • WebRTC.ventures
    Senior WebRTC Engineer
    September 2025 - Today (9 months)
    Charlottesville, VA, USA
    • - Added support to Google libwebrtc library for audio samples timings optimal for satellite phone calls in Opus codec
    • - Study lower limits on bandwidth usage of state-of-the-art video codecs in web browsers
    • - Research on narrow bandwidth audio voice transmission using custom streaming protocol over UDP datagrams and BLE GATT messages down to 800bps
    • - Improve support of Mediasoup for telehealth application
  • CosmosGroup
    Deputy CTO & Generative AI Engineer | WebRTC, Code quality, Best Practices, FastAPI, NextJS
    January 2025 - September 2025 (8 months)
    Dubai, United Arab Emirates
    • - Directed development of real-time NLP pipelines for avatar agents with intent detection and ElevenLabs voice, achieving 20× lower latency (measured end to-end)
    • - Architected a scalable AI infrastructure with 99.99 % uptime (SLO + monitoring) and managed a 6-engineer distributed team across backend, ML and voice domains.
    • - Delivered 90+ PRs (8 in one week), accelerating roadmap execution and closing a major product epic.
    • - Enhanced backend and CI/CD reliability (fixed OOM issues, flaky tests and Go vulnerabilities) earning commendations for technical leadership, expertise and commitment.
    • - Optimized CI pipelines, and expanded unit and Playwright E2E test coverage by 40 %, improving overall quality and stability.
    • - Championed code audits, best practices and testing culture across Python (FastAPI) and Node.js (Next.js) projects, raising engineering standards group wide.
    • - Designed migration from VoiceFlow to LangFlow
    • - Implemented from scratch a high-performance document classifier and LLM trainer without pre-trained models, handling 20 processes and 1000+ threads on a regular laptop, achieving +80% precision
    • - Implemented generic and vertical-agnostic RAG
  • Mafalda SFU
    founder - Chief Technology Officer
    March 2021 - Today (5 years and 3 months)
    Massively vertical and horizontal scalable SFU built on top of Mediasoup Self-managed solution up to thousand simultaneous participants in media conference and streaming sessions
    TRC
    1 year 2 months

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Education

  • Phd. Computer Engineer
    Rey Juan Carlos university
    Thesis: "Confocal microscopy visualization techniques applied to neurology"
  • Mse. Computer Engineer
    Rey Juan Carlos university
    2016
    Thesis: "NodeOS, minimal operating system for Node.js"

Skill set (8)

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