This document isn't an explainer on Feature Flags, you can find that with my amateur writeup, or literally hundreds of better writeups out there.
This document is also agnostic to the choice of service you'd use: LaunchDarkly or split.io or optimizely or whatever; that's orthogonal to this conversation.
Instead, this document is a list of considerations for implementing a client for using Feature Flags for User Interface development. Service providers usually give a simple fetch and use client and that's it; I contend that there's a lot more to care about. Let's dive in.
To encourage usage, we'd like for the developer experience to be as brutally simple as possible. So, this should be valid usage: