An ESP32 light-switch pusher, fully coded by Codex in 15 minutes
They plugged the board into their Mac and told Codex what it was, how the motor was wired and what it should do. Codex wrote all the software, and it worked exactly as wanted.
Done withCodexSpotted· by HN user zcfan· Oct 15, 2026
Result Codex wrote all of the software
“And it works exactly as I want after 15 minutes.”
Spotted: found in the wild. Details are as reported by the source above and have not been independently verified.
What they did
Built a Home Assistant device with an ESP32 that toggles a light switch. Plugged the board into their Mac and told Codex what it was, how it was wired to a motor, and what it should do. Codex wrote all the software.
How it went
It worked exactly as they wanted after 15 minutes.
Try it yourself with Codex
I have an ESP32 plugged into this computer, wired to a [servo or motor] on pin [number]. Write firmware that connects to my Wi-Fi and to Home Assistant over [MQTT or ESPHome] and exposes a switch that physically presses my light switch on and off. Flash it, test it, and tell me how to add it in Home Assistant.
A starting prompt written by Agents in the Wild. Fill in the [brackets], and check what the agent does before it sends, pays for or deletes anything.
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