Phil Calçado

Phil Calçado

@philcalcado.com

Headed engineering at companies with either billions of users and no revenue, or billions in revenue and no users.

1.1K followers4.5K following443 posts

All this talk about using only end-to-end tests for AI-written code makes me think the real winner of the AI race is going to be Buildkite.

The situation in America is such that every four years we vote on whether we’re allowed to say “Merry Christmas” or “artificial intelligence.”

Two Cybertrucks a block apart in Carroll Gardens. Haven’t seen two of these things in a day since 2024. I hope this ain’t no motherfucking bad omen.

Jev and the System One models in its wake: you either get it immediately, or you can’t see why anyone’s excited about a model that can’t write a sentence. If you get it, you’ve probably spent years torturing LLMs into production. Slides from today’s session: philcalcado.com/downloads/je...

From what I’m seeing of Jev in real-world applications, a lot of us are about to learn the hard way that you can’t just multiply probabilities 😬

Email wasn’t replaced by Slack but by four hundred Google Docs on the same topic, all named 'Untitled'. I mean, if we’re writing memos like it’s 1954, we could at least bring back the pneumatic tubes.

Being Brazilian in an American coffee shop means everyone else gets pleasant bossa nova ambience while I’m forced to understand that this man has been singing “sun, love, sea, you” on a loop for three minutes

Being Brazilian in an American coffee shop means everyone else gets pleasant bossa nova ambience while I’m forced to understand that this man has been singing “sun, love, sea, you” on a loop for three minutes

For ten years I've run the same RFC process for how engineers make technical decisions. In just a few months, AI broke its foundational assumption that a good document meant somebody had done research work So I wrote an update for an AI world—as an RFC, obviously philcalcado.com/2026/07/10/w...

philcalcado.comWriting AI-Assisted RFCsThe Structured RFC Process was built on the assumption that people hate writing. LLMs inverted it, so the format had to change to protect the one thing still scarce in a review: human attention.

I've user PagerDuty for, what, at least 15 years? I have no idea what any of the buttons in their terrible UI does except ack and resolve.

Funny that we’re rediscovering ASD-STE100, as it’s basically how most AIs have talked in fiction, and in the movie Her the whole plot was what happens when they don’t.

If people are this upset about Little Italy(!!), I can't wait to see how these bots go when the new version of the map shows Carroll Gardens as a French enclave

I mean, you don't have to tell me that the Anthropic 's Claude Code team doesn't review their AI-written code--it's pretty obvious. Just this week they broke--again--the copy and paste inside the IntelliJ terminal.

hot take: Slack is ok for chat and terrible as an email replacement the fragmentation creates more "quick meetings" because eventually the only way to know wtf is going on across channels, threads, and DMs is to summon everyone into a call and no, AI won't solve this

Having AI do the research and write your tech spec is like keeping a pristine, never-even-opened copy of The Power Broker on your living room bookshelf.

my favorite part of tech keynotes is the AI demo just sitting there like okay what are the SF gang doing today are we planning a trip are we planning a party are we choosing a restaurant are we breaking up with bae where we going AI fam

It's disheartening to watch so many companies that were building genuinely useful infrastructure and platform primitives for AI products pivot to AI coding agents.

AWS making S3 strongly consistent in 2020 quietly killed a lot of distributed systems sacred cows. A whole class of designs that used to require databases, queues, or coordination products suddenly became "just a bunch of files in S3." www.opendata.dev/blog/ingesti...

opendata.devIngesting 1Gbps of logs into ClickHouse for $180/month | OpenDataNew pipelined producer and consumer clients for OpenData Buffer, plus a ClickHouse integration with batch deduplication, move 1.1 Gbps of logs from an OTel Gateway to ClickHouse via S3 for $180/mo.