Performative: A toolkit for creating performance instruments and designing parameters in SuperCollider

Thanks for this.

However, is there any reason to include the FOSC extension in your quark?

"https://codeberg.org/madskjeldgaard/Performative".include

Installing Performative
Installing Monolithic
Installing CuePlayer
Adding path: /Users/prko/Library/Application Support/SuperCollider/downloaded-quarks/CuePlayer
CuePlayer installed
Installing wslib
Installing XML
XML installed
wslib installed
Installing fosc
Adding path: /Users/prko/Library/Application Support/SuperCollider/downloaded-quarks/fosc
fosc installed
Installing PolyBuf
Adding path: /Users/prko/Library/Application Support/SuperCollider/downloaded-quarks/PolyBuf
PolyBuf installed
Installing Singleton
Adding path: /Users/prko/Library/Application Support/SuperCollider/downloaded-quarks/Singleton
Singleton installed
Installing Pxshuf
Adding path: /Users/prko/Library/Application Support/SuperCollider/downloaded-quarks/Pxshuf
Pxshuf installed
Installing wslib
Installing XML
XML installed
wslib installed
Adding path: /Users/prko/Library/Application Support/SuperCollider/downloaded-quarks/Monolithic
Monolithic installed
Adding path: /Users/prko/Library/Application Support/SuperCollider/downloaded-quarks/Performative
Performative installed
... the class library may have to be recompiled.
-> https://codeberg.org/madskjeldgaard/Performative

According to Fosc installation gude, the recommended location is Platform.userExtensionDir or Platform.systemExtensionDir:

Install Fosc

Download the fosc master branch and unzip. Rename the ‘fosc-master’ folder to ‘fosc’. Move the ‘fosc’ folder to your SuperCollider Extensions directory. Information on installing SuperCollider extensions can be found here: Using Extensions | SuperCollider 3.14.0 Help.

Class duplication errors can be easily resolved by removing the path Fosc from the quarks paths.
I am attaching the full error logs.
error.txt (46.9 KB)

The following error is not related to FOSC, but it should be resolved.

ERROR: Found duplicate instance variable name 'data'
  in file '/Users/prko/Library/Application Support/SuperCollider/downloaded-quarks/Monolithic/Classes/Patches-Performances-Structure/SceneDef.sc'
  line 3 char 8:

I think it would be nice if users could use your package without confronting these steps!