# Design Documents for Supported Features

Supported proposals describe extensions implemented and released as fully
supported features of the library. A fully supported feature has a high-quality
implementation. If the proposal impacted the public API of the library, it
should have provided updates to a publicly available documentation about the
library, including internal documentation if necessary. A fully supported
feature is regularly tested.

Proposals that appear in `rfcs/supported` may be retained indefinitely to
provide insight into the design of existing features.
