You can use Protocol Buffers for configs without having to serialize them in its binary format. Protocol Buffers has always had its own text format [0] and now a JSON mapping [1] as well.

The proto text format is actually more flexible and less verbose than JSON since it does not require the outer enclosing set of braces and quotes around all the keys and has support for comments.

Here are a couple of examples of config files using the Protocol Buffers text format:

* Bazel CROSSTOOL: https://github.com/bazelbuild/bazel/blob/master/tools/cpp/CR...

* SyntaxNet: https://github.com/tensorflow/models/blob/master/syntaxnet/s...

[0] https://developers.google.com/protocol-buffers/docs/overview...

[1] https://developers.google.com/protocol-buffers/docs/proto3#j...