Comment by lars512

I couldn't get the why of the project from the Github page alone. Rich Hickey's post introducing it a year ago is clearer:

http://blog.cognitect.com/blog/2014/7/22/transit

JSON has become the go-to schemaless format between languages, despite being verbose and having problems with typing. Transit aims to be a general-purpose successor to JSON here.

Stronger typing allows the optional use of a more compact binary format (using MessagePack). Otherwise it too uses JSON on the wire.

Anyone who knows more, please correct me.