Working Surfacelink · 25 Oct 2026
04
A row of identical small kilns, each firing its own pot, with a conveyor carrying out film strips that show two frames side by side, a cracked pot and the same pot mended, while a figure seen from behind holds one strip up to the light, the whole scene drawn with wide empty margins on every side.
Shopify Engineering

We gave AI agents a mobile dev environment

Michael Garfinkle, Mauricio de Meirelles and David Cortes · 22 October 2026

Company story · agents · critique & review · Understanding the work

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Takeaway

Shopify gave its AI agent remote Macs to build, test and record mobile app fixes, and the agent's share of merged mobile pull requests rose from 6% to 61%.

Summary

Shopify's mobile engineers ran several AI agent tasks at once, but three or four were enough to overload a laptop, and closing the lid stopped the work. River, Shopify's AI agent in Slack, could edit iOS code on Linux but could not build or test the app. Michael Garfinkle, Mauricio de Meirelles and David Cortes describe how the team built Remote Dev, a pool of prepared remote Macs, to fix this.

Key points
  • Each agent session gets its own remote Mac, and keeping Macs ready in advance cut setup from more than 30 minutes to a few minutes.
  • For a bug fix, the agent records the broken behaviour, applies the fix and repeats the same steps, so the reviewer sees the result before and after.
  • A live stream of the running app on a web page lets designers and product managers try a change without setting anything up.
  • A fast, low-cost AI model tags every agent conversation by outcome, and the team uses the failures to improve the agent's instructions.
Implication

An engineering team can ask its AI agents for visible proof that a change works, not only passing builds. The authors also report that adoption needed internal promotion as well as better tools.

Plays
Engineering

Have a low-cost AI model label every coding agent conversation by outcome, and use the failed conversations to rewrite the agent's instructions.

Engineering

Ask an AI agent fixing a bug to record the broken behaviour, apply the fix and repeat the same steps, so the reviewer sees the result before and after.

Derived by Working Surface from the article; more in the Playbook. Source line: Just because the code compiles doesn't mean the feature behaves as expected.

Source issue

25 October 2026: AI agents and people outside engineering can change real products safely once a team has built shared templates, written rules and automated checks.