Quartz Composer
Used by 4 peopleen.wikipedia.org ↗

“Though not as often as in the past I also still make use Quartz Composer from time to time.”
David Lublin Interview, Developer, artist, co-founder (VIDVOX) · via Uses This 
“Interactive animations are typically generated using Apple's Quartz Composer.”
Deborah "CandyStations" Johnson Interview, Visual and concert designer · via Uses This