Just right after [Tiffen and Digital Film Tools announced](http://www.kremalicious.com/2008/04/first-aperture-adjustment-plugins-have-arrived/) their new image editing plugins for Aperture 2.1 Apple has released the Software Development Kit (SDK) for coding Aperture 2.1 plugins. It's available [from Apple's Developer Connection](https://connect.apple.com/cgi-bin/WebObjects/MemberSite.woa/wa/getSoftware?bundleID=20044) for registered members (registering is free). You can grab the Aperture 2.1 plugin-SDK (3D9) as a 595KB download from there and start coding. If you want to know what exactly you can do with it as a programmer you should [read those lines from Apple](http://developer.apple.com/appleapplications/aperturesdk.html).
So it should be just a matter of time before we see another bunch of plugins popping out.
