Symbiosis is a developer tool for adapting Mac OS X VST plug-ins to the Audio Unit (AU) standard. The project is released free with source code. It essentially consists of a single C++ file that you can compile into your VST project to make the plug-in compatible with the Audio Unit protocol. Optionally, you may choose to use a pre-built "wrapper plug-in" for adapting your existing VST plug-in to the AU standard without even having to recompile any source code.

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