wtf is play-json?

Play JSON is a library for the Scala programming language that helps you read, write, and manipulate JSON, the common data format used to exchange information between servers, APIs, and front-end apps. It was originally built for the Play web framework but can be used on its own in any Scala project. The library gives you tools to parse a raw JSON string into a structured tree you can navigate, and to convert that JSON directly into Scala objects (and back). You can look up nested fields using simple path operators, search recursively through a document, or build JSON from scratch using a concise syntax. It also supports validation, so you can check that incoming data matches your expectations, like ensuring a latitude is between -90 and 90, before turning it into a Scala object. This is useful for any Scala developer building an API, processing web requests, or consuming third-party services that return JSON. For example, if you receive a JSON payload describing a place with residents, you can define a Scala case class for that structure and use the library's macros to automatically convert the JSON into a typed object you can work with in your code, without hand-writing all the parsing logic. A notable strength is the range of approaches it offers. For simple cases, automatic macros handle conversion with almost no boilerplate. For more complex scenarios, a functional DSL lets you define custom readers and writers with field-level validation rules. You can also fall back to manual construction or hand-written logic when you need full control.