Squisher is a plugin for Grasshopper3D that expose three components to allow using the Squish command to flatten double curved surfaces and meshes. It is a wrapper of the Squisher Class from RhinoCommon.
Install the plugin as usual (copy the the .gha to your GH Libraries folder). You will need the latest version of Rhino 7.
The three components are available under: Tranform>Squisher
The source code is available as usual under: