Writing @Pragmatic_Eng, the #1 software engineering newsletter on Substack. Author of @EngGuidebook. Formerly Uber & Skype.
Amsterdam, The Netherlands
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Substack launched analytics insights and: wow.
Thank you to everyone reading @Pragmatic_Eng!
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Slightly more bullish on Google after seeing this
And X is back as the place where stuff happens & gets done!
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Some of the most “AI-native” mid-sized and above companies I observe are the same ones that have had dedicated infra platform and dev platform teams, “pre-AI.”
These co’s have always had robust dev tooling + release pipelines and so now AI tools have so many verification layers they can use (the existing systems.)
For startups starting from scratch, they need to eventually rebuild all those systems: from eg ones for automated testing, manual testing, FF, canary rollouts, o11y, experimentation, migrations etc etc
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I’m in the middle of a deepdive with Uber who have like ~20 custom infra / dev tools systems, a bunch of which are “pre-AI” and were there to move fast but with reliability.
So adding AI into these systems pretty straightforward, and new AI systems use the existing ones for eg verification or feedback loops or tooling
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Google integrated Gemini into every single place inside Google Workspace where it doesn't work, and nowhere where it would be useful
Like the emoji picker, so I could find this green check emoji ✅
Does anyone still work at Google who cares about UX, or users, in general?
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And, look, Google has incredible engineers, who are very talented, and solve massive and complex engineering problems. I love Google Docs, and it's a product at massive scale, is very reliable, performant etc.
But no one seems to sweat the details: either no one cares, or there's too much red tape to fix the papercuts. Like having a functional emoji picker, 20 years after the product launched. In 20 years, not one eng or designer went "you know what, this emoji picker sucks, let me fix it up." Not one!!
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What is disturbing is people building machines (LLMs) lobbying for “consciousness”.
Machines are tools we humans we create for us. An LLM is as conscious as my screwdriver, lawn mower or smartphone is - all tools we build to do X or Y.
Damning Ant founder thinks like this?!
NEW: According to a bombshell report in the New York Times, Anthropic co-founder Chris Olah threatened to walk out of Pope Leo XIV’s AI encyclical launch in May because the pope rejected the idea that machines can be conscious.
Olah’s team then privately lobbied the pope’s advisers “to take the possibility of model consciousness seriously.” Pope Leo XIV held firm.
For months, Anthropic has wined and dined theologians and religious scholars under nondisclosure agreements, hoping they would bless the idea that Claude has moral standing. thelettersfromleo.com/p/nyt-…
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GTFO if Anthropic is really making the case that AI == human and should be treated as such?!!
This is SO damning
Read it, it’s a a free article: nytimes.com/2026/09/29/us/an…
WTH Anthropic?!!
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I never got my head around why Kotlin was so quickly adopted on the backend, but Swift barely was, even if theoretically could have worked as well.
Anyone know reasons for one or the other?
Google: “[Swift] has matured into a viable systems and cloud language, pairing Rust-like data-race safety with predictable, reference-counted performance.” Announcing their Swift-based cloud SDK for backend services: cloud.google.com/blog/topics…
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@jacobtechtavern explaining it well, thank you
The main reason is that Kotlin is built on top of the JVM, so it had an enormous ecosystem of compatible Java libraries, as well as legions of existing Java backend devs who wanted to transition to a hot new tech
Swift on the server has comparatively always suffered from just a lack of ecosystem, and to complete the contrast, there weren't meaningful numbers of Objective-C backend devs
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Pretty incredible how turbopuffer are showing off how their new architecture is up to 128x slower than the old architecture… before the optimisations they are doing.
And they are doing + blogging about each optimization
Not seen a migration shared like this before, love it
we implemented batched reads in the v3 full-text engine, leading to a ~9x performance improvement. postings are stored as columns, and we were reading them a row at a time
sometimes optimization is not about being clever, but simply avoiding mistakes
tpuf.link/v3/2026-10-02
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Oh thought this is obvious: it’s a shadow system, v3. Until it’s more performant than v2 it cannot / will not serve prod.
This part (when the new system is still being ironed out, so early) is virtually never shown in public!!
the tpuf team is built different 💪
realizing it might not be clear - but v3 (new) isn't in prod yet :)
v2 (prod) is still very fast, but we're grinding v3 to make it even faster
still lots of work to do but we are moving fast
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Getting harder to tell if a trending video / post about a startup launch is real or made up; if funding happened or not.
Deleted my thread going down the rabbit hole of trying to figure out if an AI startup launch was real or fake. @lulumeservey is right:
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Even the outrage video looks like its copied from a former outrage video. And the tweet format, everything
You cannot make this up, it all smells fake fake fake
Back to trusting the real world lol
General Catalyst just co-led a $31.5 million seed round into a blatant rip-off of my company, Kled.
(skip to 40 seconds if you want to skip context)
I would typically not speak on things like this, but this level of blatant copycatting is egregious and completely unacceptable, and needs to be made an example of.
This is one of hundreds of YC startups who have conducted this disgusting behavior. Unimaginative slop that continues to get rewarded due to nepotism.
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You know what - I’ll just ignore this whole thing
And delete this thread
Decide what you believe is real, and what is fake
I could not verify if anything in this thread is real (is Replay real? Did they raise $20M? Did they copy Fastlane? Is the outrage video fabricated or copied a former outrage video?)
Both startups sell AI personas + AI videos as a service that look real
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Unironically one reason startups in the 2010s would start using "hip" technologies + blog about them (eg Clijure, Go, React etc when these were 'new' and still rare) was to hire much easier, especially solid devs who were not allowed to introduce new tech at their current co!!
Today's management tip is that if you aren't an "AI company," all of your employees are currently considering whether they should leave you for an "AI company."
"AI company" is defined as "posts on X / podcasts all the time about AI"; it is not a revenue or traction metric.
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It was not that deliberate, but more devs working there were like "oh that's a cool technology" --> "oh we're a startup we should be able to use it"
and management saw that hiring got a whole lot easier just like that
and places that played the "we're responsible adults, Java / C# is a PERFECTLY mature choice to stay on" saw their best devs simply disappear, one at a time, joining one of those startups where they could play with the latest stuff, at work
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"How did you hear about us? Was it deep research, AI, or someone else?"
"Yeah, it was deep research."
"Yes, we hear this a lot."
My recent conversation with an insurance broker. Kind of wild how quickly discovery of these small businesses went from Google to AI agents and AIO (AI optimization, similar to SEO but ofc for AI) starts mattering very much for them...
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