A lightweight Trello Power‑Up that adds a Sprint Number to cards — built when Trello’s official way to store that information became paid. This was used at Davidson Consulting / AFI‑ESCA to keep sprint metadata on cards for free with a tiny HTML/JS Power‑Up.
When Trello changed its plans, setting a sprint number on cards via official features became a paid capability. To avoid breaking our workflow, I shipped a small Power‑Up that exposes a custom field-like UI and stores the sprint number on card data through the Power‑Up client API.
This project is historical — simple HTML + JavaScript, no framework, focused on pragmatism over complexity.
- Add / edit a Sprint Number from the card sidebar (Power‑Up section).
- Store value at the card level (Power‑Up private data).
- Zero backend: can be hosted as static files (GitHub Pages / S3).
- Minimal UI → fast to use, zero learning curve.
- The Power‑Up registers a card‑badge / card‑button and a card‑back section via the Trello Power‑Up client library.
- The value is persisted using the t.set / t.get helpers (Power‑Up private data scope).
- No external services required; authentication is delegated to Trello’s Power‑Up runtime.
If needed, you can migrate data later to official Custom Fields by reading the Power‑Up private data and writing to Custom Fields.
- Serve the static files (e.g.
python -m http.serveror any static host). - In Trello, go to Power‑Ups → Create a Power‑Up (Developer Portal) and point to your manifest / index URL.
- Enable the Power‑Up on a test board and open a card to see the Sprint Number UI.
Tip: Trello Power‑Ups run inside an iframe; the client SDK handles authorization and context injection.
This was a stop‑gap for a specific moment in time (Trello plan change). Modern Trello workspaces can use Custom Fields or existing third‑party Power‑Ups for richer metadata.