Tobi Lütke: the AI agent that only works in public and transformed Shopify

Shopify's CEO tells how River — the AI agent living in the company's Slack — became a teaching workshop for 5,938 employees. The secret: she only works in public. Every conversation is visible, searchable, and teachable — and the code merge rate climbed from 36% to 77% in two months.

What River is

River is an AI agent that works like a teammate: you mention her in Slack channels, and she reads code, runs tests, opens pull requests, and queries the data warehouse. In 30 days, 5,938 employees worked with her across 4,450 channels — and about one in eight PRs merged into the codebase was authored by River.

The constraint that became a feature

The central design decision: River doesn't respond to direct messages. She only works in public channels. What felt odd became her greatest strength — knowledge spreads by osmosis, in what Tobi calls Lehrwerkstatt: the whole shop floor is the classroom, and everyone learns by watching the best work.

The result in numbers

Without retraining a model or switching models, the merge rate climbed from 36% to 77% in two months. What changed was learning: people watch River work, notice where she gets stuck, and write down what she should know — each team's accumulated taste flows into the agent.

Why it matters

The article is the clearest defense of working with AI in public: the risk isn't AI doing the work, it's AI doing the work and no one learning from it. For e-commerce, the lesson applies to any company — an organization moves at the speed of its slowest secret.