Features from optional dependencies

serde implicit feature

Enables serde

serde:

A generic serialization/deserialization framework

serde_json implicit feature

Enables serde_json

serde_json:

A JSON serialization file format

tokio implicit feature

Enables tokio

tokio:

An event-driven, non-blocking I/O platform for writing asynchronous I/O backed applications

url implicit feature

Enables url

url:

URL library for Rust, based on the WHATWG URL Standard