I want to clarify, when Web API v1 was develop, it was designed to show that a web api is not only work with SQL database, but also follow the RESTful API concept thus it was initially based on MinimaList library.
Then Web API v2 is developed to prepare for more real world use case, especially connecting to different type of database system, where MiniORM was born.
If I remember correctly, this Todo List Web API Server may be the first or early attempt to integrate with security or user authentication.