Omar U. Espejel

I have been a Developer Advocate Engineer for three years at top open-source companies in the crypto and AI industries.

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At Starknet Foundation, I'm a Developer Advocate Engineer, a role I also held at Starkware. I've presented advanced Layer2 concepts at the major crypto conferences, including ETHCC 2024, Devcon 2022, and 2023. Before that, I was a Machine Learning Engineer on the Developer Advocacy Team at 🤗 Hugging Face. Additionally, I host Hacia Afuera

Previous Roles (not all of them)

  • Developer Advocate Engineer at Starkware: Onboarded developers to the Cairo programming language and Starknet, led the creation of the Starknet Book, and represented Starkware at various conferences in Europe and America
  • Machine Learning Engineer / Developer Advocate at Hugging Face 🤗: Crafted courses on Transformers and Gradio. I've got a soft spot for (1) sentence transformers, helping sentences find their perfect match, and (2) the fastai library

Projects at Starkware and Starknet Foundation (not all of them)

  • Starknet Book: As the lead maintainer and foremost contributor to the Starknet Book which has garnered over 800 stars on Github. I've played a crucial role in establishing it as an essential resource for the Starknet community
  • Starknet San Francisco Hacker House 2023: Led the largest hacker house ever in the Ethereum Layer 2 ecosystem
  • Cairo documentation: Substantially contributed to the first docs of Cairo 1
  • Starknet's Provisions Program: Actively involved
  • Mentorship and Grants Program: Lead the mentorship and grants program for developers
  • Developer Statistics: I developed a Python program to analyze the developer ecosystem. This tool allows us to identify new developers entering the ecosystem and track their monthly commit activity
  • Basecamp: Supported on the cohort based education about Cairo and Starknet
  • Workshops at top conferences: Devcon (Bogotá), Devconnet,, ETH Latam, ETH Rio, ETH Argentina, ETH Sao Paulo, and more
  • Communities: Created and maintain Telegram developer communities (Spanish-, Portuguese-speaking and North American)

Personal Projects

  • Gradiente: startup for getting intelligence from legislative sources
  • Hacia Afuera: The most important technology and science podcast in Spanish, where we dive deep into the latest innovations and discoveries with the best guests

Recorded Live Courses/Presentations (not all of them)

Podcast where I was invited (not all of them)