This side of the river is the old world. The other side is AI. I want to ferry us all across.
RSS FeedFull-stack developer for 24+ years. I formerly led a 400-person engineering team, and I'm still a core maintainer of several large open-source projects. Everything here is something I've actually built, run, or broken: AI engineering practice, open-source dynamics, infrastructure, and security.
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Give an AI agent a city. It gives you back a film. | A City Through Time
Give a coding agent a city and a starting era. It researches the sources, pulls building and map data, builds the whole city as a white model, and lights it up era by era, from the earliest settlement to today. What comes back is a film, an old city you can walk through, and museum pages for its buildings. Two cities are lit so far: Xianyang, 6,000 years, and Rome, 2,800.
I tore down HumanLayer's source code: it leashes your coding agent, but sessions move to its cloud
HumanLayer open-sourced its approval layer for coding agents. I read the source: the engineering is real, but there is a simpler path using the CLIs' own built-in doors.
Recent Posts
I Let a Bot Run My X Account for a Month: 15 to 4,000 Followers, 37 Posts Flagged as Spam
I let scripts and an agent run my X account for a month. The followers went from 15 to 4,000, and X's own Under the Hood report for October shows 37 of my 1,937 posts flagged SPAM_HIGH_RECALL, almost all of them follow-back comments concentrated on two days. What the report says, what I suspect beyond it, and what I changed on November 12.
Claude Code reviewed its own work — out of 125 suggestions, only 2 actually worked
After 30 tasks, Claude Code reviewed its own work with /retro and proposed 125 improvements. Researchers then tested them one by one against later tasks, and only 2 fully worked. This post lays out the funnel, why most of the suggestions didn't help, and the delete-first-then-redo test that separates the keepers from the rest.
Muse's 30 Billion Tokens Don't Last Nearly as Long as They Sound
I worked backwards from Muse's own dashboard readings: the invite-reward cap is 30 billion, but what I actually received was about 4 billion, and 357M of it burned away in three days. Splitting the bill pile by pile, almost all of the money went on context being reread over and over and on the roughly 88,000-token startup cost of every new agent. At the fastest burn the 4 billion would be gone in 21 days; after the fixes it lasts 62 days, and converted into a subscription it comes to about 1.85 months of the Power tier.
A Local AWS Emulator Is Out: Agents Wrote All the Code, and the Team Reviewed Not One Line
On November 11, AWS released AWS Emulator, a local emulator of the AWS APIs covering 438 API models. All of its code was written by autonomous agents, and the team neither wrote nor reviewed a single line. I installed 1.0.322 myself, ran the four SQS steps of creating a queue, listing queues, sending a message, and receiving a message, and counted the fidelity score file that ships with the release record by record: out of 42,937 test units, only 24,243 passed, a pass rate of 56.5%. It is usable, but how many units each service actually passed is something you have to check for yourself first.
Two Months Building a Game With a Team of Agents: 6,050 Commits, 800K Lines, Then I Scrapped It
I spent two months building a Han-dynasty game with a team of AI agents: 6,050 commits on the main branch and roughly 800,000 lines of code, with the tests passing the whole time, while the game kept drifting further from playable until I scrapped it and started over. The failure was not the models. It was how I ran the team: no milestones, no stage-by-stage inspection of my own, and no visibility into how the agents talked to each other.
Claude draws the line on Nov 12: where you sit matters less than who owns your company
Anthropic's Supported Regions Policy takes effect on November 12. Any country or region not on the list is unsupported, and the policy runs three tests: where the person sits, where the company is registered, and who holds a majority stake. Passing the first test is not enough, because a Hong Kong registration or a majority mainland-Chinese stake still puts a company out, and a UnionPay logo on the checkout page only means payment can be taken.
