Flask-Restful seems pretty well maintained and it's very easy to use. If you use marshmallow it's very easy to get request validation with meaningful errors. Th

Flask-Restful seems pretty well maintained and it's very easy to use. If you use marshmallow it's very easy to get request validation with meaningful errors. There is also a package called apispec that can make a Swagger specification from your flask paths and marshmallow models. I like Django but unless I'm using it already I've not seen a reason to use it instead of these simpler libraries for APIs.