Great Crate. Possible to Merge back to tokio-tls?

This is a great crate. The state of affair of async-tls is problematic. Its update to rustls 0.20 is still not released, whereas users are providing continuous feedback to tokio-tls.

It seems to me that futures-rustls is compatible with either tokio-tls and async-tls. Is it possible to use rust features to provide a different configuration for different needs of backends.

For example, is it possible to use features = ['tokio', 'futures'] where the default feature is 'tokio' so that tokio users won't feel any change, while enabling async-std or gio users to benefit from the community and continuous improvement of the library by enabling the 'futures' feature for their choice of backend?

Start by reviewing futures-rustls's current feature configuration and how it relates to tokio-tls, async-tls, and futures-rustls backends. Compare the rustls 0.20 update status and assess whether tokio, futures, async-std, and gio users can be supported through separate features. Done means the compatibility and feature-design question has a settled implementation plan.