[lnmx]

So, EDN [1] is a formalization of Clojure data-literal syntax that includes tagged types, has a text representation, and no built-in caching.

Fressian [2] supports the same types and extensibility as EDN, has a compact binary encoding, and the serializer/writer can choose its own caching strategy (so-called domain-specific caching[3]). I believe it was created to provide a serialization format for Datomic.

Transit sounds like an evolution of EDN and Fressian: make the bottom layer pluggable to support human-readable/browser-friendly JSON or use the well-established msgpack for compactness. Caching is still there, but it can only be used for keywords/strings/symbols/etc. instead of arbitrary values like Fressian -- probably a good trade-off for simplicity.

[1]: http://edn-format.org [2]: http://fressian.org [3]: https://github.com/Datomic/fressian/wiki/Caching

[devin]

Nailed it.