That's a great question, and we are preparing a write-up talking about the D3 libraries ecosystem at this moment. There is certainly a good amount of D3 librari

That's a great question, and we are preparing a write-up talking about the D3 libraries ecosystem at this moment. There is certainly a good amount of D3 libraries out there, and it could be frustrating to do some research on so many! Specifically, stacked against C3, Britecharts has a more 'D3-like' API, while C3 is a lot more declarative. This means that on C3, we will render charts by passing large configuration objects, while in Britecharts we strive to use a different API, chaining settings like we do on D3. Also, C3 hasn't been updated to D3 v4, and we can say it is an inactive project.