Managing the Library Folder

I have an asset build process running on a remote machine. Right now, I'm blowing away the library in between builds. Otherwise, the build machine library will eventually grow too big. I can make a cap on the library and wipe it, but I'll be hitting some big spikes, because there are some common assets on the build node in addition to assets that are being built.

Any ideas?

I don't think AssetDatabase.MoveAssetToTrash deletes the corresponding library folder, but I haven't tested it.