Overview of Jsonnet

Jsonnet was born out of Google by an engineer who wanted to improve upon and extend an internal configuration language known as Google Configuration Language (GCL). It was initially released in 2014 – the same year as Kubernetes. It is truly fortuitous that we received a tool that can generate YAML and the biggest abuser of YAML in the same year. Google giveth and Google taketh away.

At its core, Jsonnet is an extension of JSON – the common, ubiquitous method for sharing data between applications in a human-readable way. This means that any JSON document is also a valid Jsonnet program and will be emitted unchanged when run. Naturally, requiring Jsonnet to be a language that must operate within the constraints of the JSON specification can be limiting, and you will undoubtedly encounter oddities in the language attributable to those constraints.

Jsonnet does not endeavor to be a fully featured programming language as blissful to use as, say,...