Two weeks ago at the Freebase user group meeting, Freebase hacker at large Will Moffat showed us a preview of Acre, a new tool for building apps on Freebase.

Here’s a 15 minute video of his talk:

(Apologies for the lighting, which makes some of the overhead projection impossible to read, but hopefully you can follow along anyway.)

To summarise/paraphrase:

• Acre is a hosted server-side Javascript development environment based on Mozilla’s Rhino
• Acre ties into the Freebase Query Editor: build a query, then build an app based on it
• Apps are written in Javascript, using any templating engine you like (we use Mjt)
• Output can be HTML, RSS, XML, JSON, HTTP redirect…
• Point people at a permanent URL for your app’s output
• Make building blocks for mashups, or even your own API

The timeline for this thing being available is somewhere in the range of a month or so; we’re not promising any particular date, but stay tuned because you can bet we’ll be talking about it a lot when it’s ready for prime time.