It may be my limited experience with C#, but I really missed Rust/serde when deserializing a config file into a class/struct. (Actually INI not JSON.) It feels like doing error handling twice: first catching parser exceptions, and later checking for null fields everywhere. (Basically I was forced to default-construct the object before parsing, which either means nullable fields, or having hardcoded defaults for every field.) I guess the pragmatic thing is to turn off null warnings and accept that it may fail later.