The story
Twenty years, three acts
Every engineer's career is a story about what they were trusted with. Mine runs from an island where I fixed the machines myself, to the trading floor, to the front door of a new financial world. Then comes the strangest chapter: everything the career taught turned out to be preparation for a question nobody was asking yet. You will see it coming before I did. The thread underneath it has its own page.
- Act I · The island and the floor
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Origins
San Juan · at fourteen
The kid who fixed the machines
Puerto Rico, before cloud anything. If you wanted a computer that worked, somebody had to build it - and by fourteen, people in San Juan were paying me to be that somebody. By high school I was also running a two-hundred-member youth organization: activities, budget, fundraising, a fifteen-person board. Machines that obey and people who volunteer are different problems. I got an early start on both. For senior year of high school, I took a one-way ticket to Florida.
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Engineering
Cornell · five years
The study of representing the world
Information science, then a master's in engineering management. Information science asks one great question - how do you represent the real world inside a computer? It turned out to be the question I would spend my whole career answering. I taught calculus to other students and kept the books for the Hispanic engineers' chapter, because apparently I cannot be near an organization without running part of it.
And in the summer of 2009 came my first corporate technology job: building databases at Sony Music in New York, while selling clothes in a SoHo store on the side. This site is the first public bio that job has ever appeared in.
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Engineering
Three summers, one team
Goldman Sachs, from the inside
The same trade-processing team took me back three summers running - trust you only earn by shipping. I built the tools that check the firm's records against its own risk systems, and somewhere in there I started running the mentoring program for the incoming interns. Teaching the next class while still being one: a pattern that never stopped.
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Engineering
Then the floor itself
Systems that are not allowed to fail
Securities technology: the systems that double-check the firm's trades and file the reports the law requires. When your software sits between a bank and its regulators, correctness is not a virtue - it is the whole job. I built a query service designed to be shared firm-wide as internal open source, and wrote in the firm's own in-house programming language. I also helped stand up a round-the-clock operation, spanning dozens of teams, that catches errors before they become anyone's worst day.
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The hidden hours
Every morning, 5:50
The double life
Here is the part my colleagues never saw. Before the floor each day there was a study hall, an old library, and a discipline of close reading that predates every system I have ever shipped. That second life ran in parallel for years, quietly training me for work I could not yet imagine. That story has its own page.
- Act II · The leap, and the long apprenticeship
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June 2015
Two names, one month
I gave up the “perfect job” - the one you are not supposed to leave. That same month I incorporated two companies: LazoffTech for client engineering, and a second one for the long research project running underneath. The first has funded the second ever since. Every job that followed looked like client work and turned out, in hindsight, to be the curriculum.
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Research
The next two years
Lesson one: the data is the product
First came a learning platform built with a team in Israel, then a ground-up rebuild of a much-loved video library. Two years of learning the lesson every senior engineer eventually learns: organizing the material is harder than writing the code - and the structure you choose for knowledge determines everything you can do with it later.
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September 2016
A list called “Websites to make”
One year in, I wrote myself a five-line plan. The first line was this website - “the main site where all the projects are listed.” It took nearly ten years, and most of that list is now real. The first line is the page you are reading.
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Engineering
Six years
The front door to a new financial world
I joined ConsenSys through its education arm, building the platform that taught developers an entirely new way to program. I stayed six years and left as the senior engineering manager responsible for every website behind MetaMask and consensys.io - the pages millions of people walked through to enter an economy that had not existed a decade earlier. Running the web presence of software that guards people's money teaches you a professional level of paranoia. I recommend it.
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Engineering
Three and a half years
The company whose product is an oracle
Chainlink builds the systems that tell blockchains the truth about the outside world - prices, events, facts. The industry's own name for them: oracles. I spent three and a half years building the sites and tools its developers rely on - three of those years while still running the web at ConsenSys, both engagements flowing through the research company. By then the joke was writing itself: my day job was helping machines report facts with sources, and so was everything else.
- Act III · The machines arrive
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Engineering
2023
A machine in the house
Everything the career taught - connecting information, making it findable, running systems that do not lose things - pointed at one place, and it was not a data center. It was a machine on my own shelf, running models I could open up and inspect, holding data that never leaves the building. I stopped renting my computing and started owning it.
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The rule that runs through everything
An answer arrives with the source it came from - or it does not arrive.
I found the rule on the oldest shelf in the world, and I wrote it into the code.
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Engineering
2026
The year of the machines
When the AI tools matured, two decades of collecting became fuel. In one year I shipped more new projects than in every earlier year combined: maps of knowledge, honest tests, tireless helpers, and an entire fleet of teaching sites. All of it built and run by one person, with a rack of machines at home. What every engineer dreamed of - one person building like a team - finally exists. It rewards exactly the people who spent years preparing for it.
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Research
Now
The room where the voices answer
The strangest thing I have ever built: I taught a machine to read the oldest library I know, and to answer the honest way - name where you read it, or say nothing. Eight voices now answer from that library, out loud, from a machine in my house, and anyone can talk to them. It is my grounding testbed: the hardest citation problem I could find, running in public.
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The rule, measured
Does the rule hold?
It holds. Every answer must name a real source you can go and look up, verified word for word against the actual text - and if no source exists, the system says nothing. Only a model that clears every check ships.
That discipline - cite or stay silent, measured, in public - is what I want to bring to a team working on AI you have to be able to trust. The research behind it is at jew.tech; the productized version is Digital Twin Pro.