The problem with JSON is that it's only solving the trivial first part of the problem. You still have essentially a parser after the JSON parser to handle your

The problem with JSON is that it's only solving the trivial first part of the problem. You still have essentially a parser after the JSON parser to handle your own logic. The more features you add, the closer down the path from simple towards Yaml and XML you move. But even with XML, you'll have to implement your own domain-specific validation for those things not represented by schemas etc. In the end, your simple format isn't so simple anymore. Sometimes I wish for specific configuration formats which are fit for the purpose instead of the bolted-on monstrosities like jinja-templated yaml. This has all the problems you mention, but I think we're losing something by the culture that we're not supposed to write our own parsers anymore.