@zegnat/fuzzystringify is a library for fuzzing the JSON version of JavaScript objects. It is meant to be used for JSON APIs to ensure the API consumers do not grow to depend on a specific formatting.

Back in 2017, @abhayachauhan was working for PageUp and released an extension for Newtonsoft Json.Net called PageUp.FuzzySerializer. Read more about this on (a Wayback Machine copy of) their blog: Loosen coupling over APIs – The Fuzzy Serializer.

As of 2024, this fuzzy serialiser is still in use by PageUp and the blog post (although no longer live) is still linked to on their Developer Portal (archived).

The idea is interesting, so in March 2024 this repository was created to see if the same effect could easily be implemented in JavaScript. The original GitHub repository (PageUpPeopleOrg/PageUp.FuzzySerializer) no longer exists, but an old fork was discovered: stu-mck/PageUp.FuzzySerializer. This made it possible to port over the tests and start developing a fuzzer from scratch.