In this session, I'll discuss something that may seem completely trivial - replacing a JSON parser in a large codebase. A year ago, we decided to switch from Newtonsoft.Json to System.Text.Json in an open-source framework. Because we had a lot of custom converters, used advanced concepts such as JSON patching, encrypting parts of the object tree, and relied on several unique features of Newtonsoft.Json, it has become a long and complex journey. I'll discuss the differences between the two libraries, what we learned, and how the change improved the framework's performance and memory efficiency.


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Lessons learned: From Newtonsoft.Json to System.Text.Json in Large Codebases