Cargo Features

[dependencies]
rs_observable = { version = "0.1.4", default-features = false, features = ["all", "single", "tokio"] }
default = tokio

The tokio feature is set by default whenever rs_observable is added without default-features = false somewhere in the dependency tree.

all = single, tokio
single all?
tokio default all?

rs_observable has 4 features without comments.