# How we turned the Replay keynote surprise into an open-source embedded playground

DevFeed: [How we turned the Replay keynote surprise into an open-source embedded playground](<https://devfeed.tech/articles/how-we-turned-the-replay-keynote-surprise-into-an-open-source-embedded-playground-35873.md>)

Original publisher: [Read original article](<https://temporal.io/blog/how-we-turned-replay-keynote-surprise-open-source-embedded-playground>)

Author: Shy Ruparel

Published: 2026-05-26T00:00:00Z

Content type: article

Language: en

Sources: [Temporal Blog](<https://devfeed.tech/sources/temporal-blog.md>)

Topics: [Open Source](<https://devfeed.tech/topics/open-source.md>), [Embedded Systems](<https://devfeed.tech/topics/embedded-systems.md>), [ESP32-S3](<https://devfeed.tech/topics/esp32-s3.md>), [MicroPython](<https://devfeed.tech/topics/micropython.md>), [kicad](<https://devfeed.tech/topics/kicad.md>)

Tags: [embedded](<https://devfeed.tech/tags/embedded.md>), [embedded-systems](<https://devfeed.tech/tags/embedded-systems.md>), [esp32-s3](<https://devfeed.tech/tags/esp32-s3.md>), [kicad](<https://devfeed.tech/tags/kicad.md>), [micropython](<https://devfeed.tech/tags/micropython.md>), [open-hardware](<https://devfeed.tech/tags/open-hardware.md>), [open-source](<https://devfeed.tech/tags/open-source.md>), [temporal-voices](<https://devfeed.tech/tags/temporal-voices.md>)

## AI overview

Temporal describes how it designed and distributed 2,000 hackable ESP32-S3 badges at Replay and then released the badge's firmware, hardware designs, fabrication files, documentation, tools, examples, and community app infrastructure as an open-source ecosystem.

## Source excerpt

We handed out 2,000 tiny hackable computers at Replay. Now the whole ecosystem is open source. Here's the story of how we built and shipped them.