Member of Technical Staff at OpenAI·2024 – now

Look after the systems OpenAI trains its models on

I was personally on call for some gpt-oss training runs, so you know those models were looked after well.

Talk to me about
Flying

Went flying for five hours while Codex wrote my code

Codex took maybe fifteen minutes to write it, run the tests, and fix the bugs. My day off beat a pre-AI workday.

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Wednesday Wisdom

Wrote 136 Wednesday Wisdom essays for engineers

I've written on why you should never trust a senior engineer who doesn't code, and on the agile waterfall.

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AI chip design

Gave away my AI chip design instead of starting a company

Drawing on TPUs at Google and GPUs at Nvidia, I wrote it up as a free document that grew from 80 to 151 pages.

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Principal Engineer at Amazon·2018 – 2024

Worked at Facebook, Confluent, and Amazon on core systems

I worked on Facebook's internal cloud, Confluent's data in motion, and Amazon's People Engine for 2M colleagues.

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Senior Staff Site Reliability Engineer (SRE-SWE) at Google·2006 – 2018

Led reliability teams at Google in Zurich and Cambridge

I also worked on TPUs there. Seven years after leaving Google, I still typed 'blaze build'.

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Owner at Multigroep·1992 – 2006

Owned a group of tech companies near Amsterdam

After too many years consulting at a large bank, I wrote a satire on designing unmanageable, insecure systems.

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Early life·1982

Still tinkering with a language my math teacher showed me

I was writing BASIC and assembler then. In 1990 I started a Comal interpreter in C, now open source.

Talk to me about
Jos Visser

Jos Visser⁠

OpenAI

Member of Technical Staff at OpenAI

About

I'm a Member of Technical Staff at OpenAI, and I led SRE teams at Google for over a decade.

Experiences

  1. Member of Technical Staff at OpenAILook after the systems OpenAI trains its models on

    I was personally on call for some gpt-oss training runs, so you know those models were looked after well.

  2. FlyingWent flying for five hours while Codex wrote my code

    Codex took maybe fifteen minutes to write it, run the tests, and fix the bugs. My day off beat a pre-AI workday.

  3. Wednesday WisdomWrote 136 Wednesday Wisdom essays for engineers

    I've written on why you should never trust a senior engineer who doesn't code, and on the agile waterfall.

  4. AI chip designGave away my AI chip design instead of starting a company

    Drawing on TPUs at Google and GPUs at Nvidia, I wrote it up as a free document that grew from 80 to 151 pages.

  5. Principal Engineer at AmazonWorked at Facebook, Confluent, and Amazon on core systems

    I worked on Facebook's internal cloud, Confluent's data in motion, and Amazon's People Engine for 2M colleagues.

  6. Senior Staff Site Reliability Engineer (SRE-SWE) at GoogleLed reliability teams at Google in Zurich and Cambridge

    I also worked on TPUs there. Seven years after leaving Google, I still typed 'blaze build'.

  7. Owner at MultigroepOwned a group of tech companies near Amsterdam

    After too many years consulting at a large bank, I wrote a satire on designing unmanageable, insecure systems.

  8. Early lifeStill tinkering with a language my math teacher showed me

    I was writing BASIC and assembler then. In 1990 I started a Comal interpreter in C, now open source.

Follow Jos for more...

LinkedIn

© 2026 Delphi · Terms · Privacy

Jos Visser

Jos Visser⁠

OpenAI

Member of Technical Staff at OpenAI

About

I'm a Member of Technical Staff at OpenAI, and I led SRE teams at Google for over a decade.

Experiences

  1. Member of Technical Staff at OpenAILook after the systems OpenAI trains its models on

    I was personally on call for some gpt-oss training runs, so you know those models were looked after well.

  2. FlyingWent flying for five hours while Codex wrote my code

    Codex took maybe fifteen minutes to write it, run the tests, and fix the bugs. My day off beat a pre-AI workday.

  3. Wednesday WisdomWrote 136 Wednesday Wisdom essays for engineers

    I've written on why you should never trust a senior engineer who doesn't code, and on the agile waterfall.

  4. AI chip designGave away my AI chip design instead of starting a company

    Drawing on TPUs at Google and GPUs at Nvidia, I wrote it up as a free document that grew from 80 to 151 pages.

  5. Principal Engineer at AmazonWorked at Facebook, Confluent, and Amazon on core systems

    I worked on Facebook's internal cloud, Confluent's data in motion, and Amazon's People Engine for 2M colleagues.

  6. Senior Staff Site Reliability Engineer (SRE-SWE) at GoogleLed reliability teams at Google in Zurich and Cambridge

    I also worked on TPUs there. Seven years after leaving Google, I still typed 'blaze build'.

  7. Owner at MultigroepOwned a group of tech companies near Amsterdam

    After too many years consulting at a large bank, I wrote a satire on designing unmanageable, insecure systems.

  8. Early lifeStill tinkering with a language my math teacher showed me

    I was writing BASIC and assembler then. In 1990 I started a Comal interpreter in C, now open source.

Follow Jos for more...

LinkedIn

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