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.

Academic experience

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.

I started my Ph.D., but currently is on-hold. My PhD thesis was Co-focal microscope techniques applied to neurology, where I was compositing multi-gigabyte high resolution multi-layer microscope scan images of neurons to generate 3D models. My Ph.D. thesis director was Ph.D. Sofía Bayona-Beriso.

  • NodeOS

    • Novática 236.pdf, April-June 2016:

      They were also given honorable mentions for the projects:


      NodeOS of Jesús Leganés Combarro (Rey Juan Carlos University).

      Original (spanish)

      Se entregaron también menciones especiales para los proyectos:


      NodeOS de Jesús Leganés Combarro (Universidad Rey Juan Carlos).

    • The Case for Writing Network Drivers in High-Level Programming Languages, 13 September 2019:

      4.10.1 Related work. JavaScript is rarely used for low-level code, the most OS-like projects are NodeOS and OS.js. NodeOS uses the Linux kernel with Node.js as user space. OS.js runs a window manager and applications in the browser and is backed by a server running Node.js on a normal OS. Neither of these implements driver-level code in JavaScript.

  • ShareIt!

    • Introducing ufo.js: A browser-oriented p2p network.pdf, February 2014:

      Among real life applications using the datachannel as best as they can, we should definitely mention shareit and sharefest. Such applications allow browsers to share files in the absence of any form of upload to external servers, as opposed to well-known services such as Dropbox or Google Drive. Both shareit and sharefest use an external server holding and managing a connection to each peer; these connections are used to accomplish all the signaling procedures between peers. Thus the actual p2p communication happens during file transfers.

      Note: ShareIt! used an external server to bootstrap the initial discovery and signaling with other peers, once they were connected to at least another peer and being part of the P2P network, the discovery and signaling with new peers was done directly between peers over the P2P network itself, leaving the connection with the external server as a fallback mechanims.


Interesting facts

  • Co-founder of Spain Robotic & Domotic Association
  • Co-founder of AlcorcónWireless and Ex-Member of MadridWireless communities
  • Participant of Spring Mathematics Championship, Madrid 2004
  • Grant receiver for 3DS - 3 Days Startup, Madrid 2012
  • WebRTC pioneer since 2012
  • NodeOS lead developer, and Mafalda SFU founder
  • Several years Madrid San Silvestre Vallecana 10km runner (53’38”, 2019)
  • Currently learning chinese and arabic JustForFun™

Countries visited

I’ve been so far in 18 Century Club territories, 16 countries, and 3 continents

  • Europe
    • 🇪🇺 European Union
      • 🇪🇸 Spain: Madrid, Valencia, Toledo, Segovia, Tarragona, Castellón, Cadiz, Sevilla, Almería, Oviedo, Malaga, Merida, Barcelona, Coruña, Pontevedra, Zamora, Zaragoza, Teruel
        • 🇮🇨 Canary Islands: Gran Canaria (Las Palmas, Maspalomas), Fuerteventura
      • 🇵🇹 Portugal: Oporto, Lisboa
      • 🇩🇪 Germany: Hamburg
      • 🇦🇹 Austria: Viena
      • 🇨🇿 Czech Republic: Brno
      • 🇮🇹 Italy: Milan
      • 🇧🇪 Belgium: Bruselas, Bruges
      • 🇧🇬 Bulgaria: Sofia
      • 🇵🇱 Poland: Katowice
    • 🇬🇧 United Kingdom:
      • 🇬🇮 Gibraltar
      • 🏴󠁧󠁢󠁥󠁮󠁧󠁿 England: London
      • 🇮🇪 Ireland: Dublin
    • 🇨🇭 Switzerland: Zurich
  • Africa
    • 🇲🇦 Morocco: Marrakech
  • Asia
    • 🇶🇦 Qatar: Doha
    • 🇮🇳 India: Bangalore
    • 🇦🇪 United Arab Emirates: Abu Dhabi, Dubai, Al Ain

Recomendations, testimonies & quotes

Recomendations from co-workers and managers of my previous job companies, and testimonies from clients about my freelance projects.


Jorge Abrines, CTO of Vaelsys, July 2012:

Jesus is a worker with a lot of knowledge in several technical areas, from low level programming up to scripting languages, and including devices integration that’s where he was helping us. He is a person with a great interest for learning and improve himself each day, and I recommend him specially for his technical expertise and aptitudes.

Diego González, Founder of SciArt Lab | Software Engineer / Blockchain Expert at Docuten, May 2014:

Jesus is much more than a brilliant developer. He loves to achieve complex goals just by using a keyboard and a bunch of code lines. I would describe him as a creative and genius mind, a geek with a lot of technical skills but also with engagement and passion. Jesus is that kind of guy that can launch a project to the top. I strongly recommend him.

Juan Francisco Gato Luis, Android R+D & Singer, May 2014:

I don’t need so much words to recommend Jesús. Just one case, if you need a man that works for a project and not for money, this guy could reach it. He just can do it, and if he don’t [know] how to made it, he will reach a way.

Juan Searle, CTO at Full Circle_ apps, December 2020:

“I agree a lot with everything [you’ve proposed]. I’m surprised that you have owned the code in just some hours, without documentation and without mentoring from our side. Cool!

This afternoon we’ll have a call with the client and let’s see if we get their aproval for the testing/refactoring, I’ll keep you updated. We’re going to propose it as a critical action to be done.”

“Tell you that it has been a pleasure to count on you for this job: serious, decisive and accessible. My idea is to have someone to whom I can ask for NodeJs development and evolution of projects already done like this one from TVN, and I think I’ve found the right person. If you are still available I will count on you in future projects without a doubt.”

Isabel Dorado, Remote Talent Advocate at Circular, December 2020:

Senior developer with experience leading teams and really hands on. Background in both back and frontend development. His expertise is related to Python, Node and C++. Spanish and English!

Miguel Muñoz Royo, Business and Technical Lead at UST Global, December 2020:

The truth is that the conversation with Jesús has been very good. He’s a Node.js super architect with experience more than enough for the profile we are looking for.

Judith Aranda Rubio, Talent Management at Ferrovial, December 2020:

Wide development experiences and skills.

Alberto Doval Iglesias, CTO at Councilbox, June 2021:

Jesus was working with us at Councilbox in a very ambitious project to replace our video conferencing server. His experience at webrtc helped us complete the migration of our video infrastructure to Mediasoup.

James Croney, Tech Lead at Virbela, November 2021:

“You have good eyes for spotting best approaches and practices for things, even if people ignore them.”

“You have a good head on your shoulders about code and you offer good insights about things.”

Sol Rengifo Calderón, founder of Gud, July 2022:

Working with Jesus has been a luxury. He has been able to offer us an accurate and detailed view of the status of the project and has advised us at all times in an accurate, clear, honest and very professional manner. We will continue to collaborate with him without a doubt.

Kushagra Vaish, CTO and co-founder of Dyte, January 2023:

“Project you touch, project that increase its quality globally.”

Alexander Gavazov, Principal Tech & Lead at Intellias, September 2023 (LinkedIn comment):

Having interacted with Jesus, I can confidently recommend him not only as a principal in JS (end-to-end), but also for any matters related to engineering. His extensive knowledge and commitment are evident in every task he undertakes, showcasing a high level of expertise in every project.

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