NodaTime 

Noda Time is a date and time API acting as an alternative to the built-in DateTime/DateTimeOffset etc types built into the .NET framework.

Provides serialization support between Noda Time and Json.NET.

Provides extra types which may be useful when testing code which uses Noda Time, such as a fake programmable implementation of IClock and a time zone which has a fixed transition. These types are also used to test Noda Time itself.

Provides serialization support between Noda Time and Google.Protobuf