Dor Kalev

Engineering leader, serial founder, and writer. Building at the intersection of technology and people.

Startups, code, and the quest for glory

I've spent the better part of two decades building technology companies from the ground up. I started with mathematics at the Open University of Israel, drawn to the elegance of formal systems, then found that same elegance in code—in the architecture of systems that serve millions.

At Seeking Alpha, I cut my teeth on large-scale engineering. That led to FTBpro, which became 90min—the world's largest fan-generated football media platform. As CTO, I grew the platform to 130 million pageviews a month, scaling 20x without spending an extra penny on infrastructure.

Then came the pull of building something truly my own. I co-founded Contextors, a natural language processing startup in Tel Aviv. We built a novel sentence parser and NLP API—entity recognition, question-answering, sentiment analysis. We raised funding, made scientific breakthroughs, and ultimately had to shut it down. I wrote about the aftermath in Black Clouds Over the Skyline.

I founded Kapai, then a.tax—a platform for tax management—drawn each time by the impulse to build something that simplifies the complex. I also created HaDaf (daff.co.il), a digital stage for independent Hebrew writing that grew to host 342 authors and over 3,000 works. At Labguru, I led engineering for a platform that helps scientists manage their research.

Now I'm at BoltX, a Physical AI company building intelligent co-pilots for industrial maintenance teams—tackling the skilled-labor crisis in manufacturing.

Through it all, I write. Poetry and prose in Hebrew—165 pieces and counting. The Blindman series on Medium. And daily on Facebook, where I write about democracy, human rights, and what it means to be a citizen who gives a damn.

The journey so far

  • 2025 – Present
    Engineering
    Physical AI company powering a new age of machine experts. Tackling the skilled-labor crisis in industrial maintenance.
  • 2025
    Co-Founder & CTO
    a.tax
    Tax management platform.
  • 2021
    Founder
    Digital stage for independent Hebrew writing. 342 authors, 3,000+ works.
  • 2023 – 2025
    VP Engineering
    Labguru (BioData)
    Led engineering for a lab management platform used by scientists worldwide.
  • 2018 – 2023
    Self-Employed
    21tech
  • 2017
    Co-Founder & CTO
    Kapai (kap.ai)
  • 2014 – 2017
    Co-Founder & CTO
    Contextors
    Natural language processing startup. Built novel sentence parsing and NLP APIs.
  • 2012 – 2014
    CTO
    FTBpro / 90min
    Scaled the world's largest fan-generated football media platform to 130M pageviews/month.
  • 2007 – 2011
    Deputy VP R&D
    Seeking Alpha

Selected pieces

I write daily on Facebook about democracy and human rights in Israel. In Hebrew, I published 165 poems and stories on HaDaf. In English, on Medium.

Talks

Growing X20 Without Spending an Extra Penny on Hosting
2014 · CDN scaling strategies at FTBpro
The Dark Side of Single-Page Applications
Rails Israel, 2013 · Lessons from migrating FTBpro to Backbone