--- title: "Ignition: Flashing 2,300 conference badges with Temporal" url: https://daily.dev/posts/ignition-flashing-2-300-conference-badges-with-temporal-4bgcem7oo source_url: https://temporal.io/blog/ignition-flashing-2-300-conference-badges-with-temporal type: article source: "Temporal" published: 2026-08-06T10:37:23.773Z updated: 2026-08-06T10:39:26.255Z tags: ["python", "embedded", "workflow-orchestration"] reading_time: 13 upvotes: 0 comments: 0 language: en --- > ## Documentation Index > Fetch the complete documentation index at: https://daily.dev/llms.txt > Use this file to discover all available pages before exploring further. # Ignition: Flashing 2,300 conference badges with Temporal **[Temporal](https://daily.dev/sources/temporal)** · 13 min read · 0 upvotes · 0 comments ## Summary A detailed account of building Ignition, a Temporal-powered firmware flashing system used to flash 2,300 ESP32-based conference badges in two days at the Replay 2026 conference. The system used a parent-child Workflow model where each physical badge carrier mapped to one parent FlashBadgesWorkflow with 32 per-badge child workflows. Key engineering challenges included handling USB re-enumeration when QA firmware caused devices to reappear under different port names, separating flash success from actual boot validation, and running six fully isolated local Temporal servers on laptops to avoid a shared failure domain. The architecture wrapped esptool with durable state, retry policies, heartbeated activities, and boot verification to turn a fragile manual process into a reliable production line operable by non-experts. ## Full article daily.dev links to this article rather than hosting it. Read it at the original source: ## Similar posts on daily.dev - [I built 2,000 badges for Replay and I’m not sure I’ve slept since December](https://daily.dev/posts/i-built-2-000-badges-for-replay-and-i-m-not-sure-i-ve-slept-since-december-6zq7asu5z) · Temporal · 0 upvotes · 0 comments - [How we turned the Replay keynote surprise into an open-source embedded playground](https://daily.dev/posts/how-we-turned-the-replay-keynote-surprise-into-an-open-source-embedded-playground-jvmlbu4zy) · Temporal · 0 upvotes · 0 comments - [An Event Badge Re-Imagined As A Cyberdeck](https://daily.dev/posts/an-event-badge-re-imagined-as-a-cyberdeck-yqapkukqe) · Hackaday · 0 upvotes · 0 comments - [Building Festival Badges That Sync Themselves Up](https://daily.dev/posts/building-festival-badges-that-sync-themselves-up-k4edbiijo) · Hackaday · 0 upvotes · 0 comments --- Tags: [#python](https://daily.dev/tags/python), [#embedded](https://daily.dev/tags/embedded), [#workflow-orchestration](https://daily.dev/tags/workflow-orchestration) [View this post on daily.dev](https://daily.dev/posts/ignition-flashing-2-300-conference-badges-with-temporal-4bgcem7oo)