This is the Mercury, a tool for rapidly iterating on visual ideas. I worked on this during an Amii Hack Night and presented it at DemoCamp 57.
Here's a demo video: https://www.loom.com/share/bc75679fd59b4380b764b0f502ce051a?sid=d06add8c-9eb4-4a0b-8dea-4564cdc384c1
Detailed instructions on how to get this running are available in the submodules: Mercury UI and Mercury Backend.