Badge request: Joind.in

[Joind.in](https://joind.in/) is a popular platform for conference talks where speakers and organizers can list talks and collect reviews from attendees.

It would be great if there was a badge that I could put in my presentations' README files (I write them in [reveal.js](http://lab.hakim.se/reveal-js/#/) and host the repositories on GitHub ([example](https://github.com/stevegrunwell/taking-the-web-offline)) with the aggregate score of the most recent time I've given a presentation:

[](https://legacy.joind.in/talk/view/16802)

Joind.in [provides an API](http://joindin.github.io/joindin-api/) with information about talks when provided a talk ID.

Thanks for your consideration!

Start with the Joind.in API documentation linked in the issue and review existing Shields badge implementations for external services. The work is done when a badge accepts a Joind.in talk ID, displays the latest aggregate score, and links to the talk page.

Written by the indexing model from the issue text.