Missing alternative

[mrtank]

Hi,

Let me know what library I missed here

There is a pure F# alternative, which also handles F# types. Union types serializable with a lot of configurability.
https://github.com/Tarmil/FSharp.SystemTextJson

[bartelink]

I think https://github.com/jet/FsCodec (which I maintain) should be placed alongside that (it similar in what it does, i.e. both are extensions around Sysntex.Text.Json, but provides less fewer rendering options for DUs and is hence much less code)