What is Nexema?

What is Nexema?

Nexema born as a side project when I was working in a very large project and writing .proto files for the HTTP services got me a lot of heaches. I was sure a lot of optimizations could be be done, either on the protocol or in any plugin.

Nexema is an alternative for Protobuf or MessagePack that aims to be developer-friendly. You write your types and services one time, you run a command and then you have source code files for every language you want.

Another one?

The first thing that maybe came to your mind was: really? Another data interchange format?
Nexema is not just another data interchange format, it aims to solve common problems that appears when working with Protobuf or MessagePack for example.

  • MessagePack misses an schema, if you want to use it for sharing data in a HTTP server, probably you will end up writing classes for the backend and then for the client.
  • Protobuf misses some OOP features, if you want inheritance, you will probability write another message and then append it to the "extended" version. If you want nullability, you have optional, but this does not generate true nullable types is some languages. Nexema gives you more flexibility when generating code. You have enums, structs, unions, inheritance, comments. You can select what kind of serialization process does the generated code use (incoming).


  • Inheritance, write base types and then extend them
  • Unions, like classes but one field can be set at time
  • Enums
  • You decide what to generate, if you want only types, you got it. If you want types and serialization, you got it.
  • Faster JSON serialization, made by generating json serialization/deserialization code. No more reflection.


  • Auto generated HTTP/GRPC services
  • Realtime serialization/deserialization, if you are working with large types, instead of serializing/deserializing when creating the object, you can keep the buffer in the type and read from it when necessary.
  • Dependencies, reuse your types in multiple projects