LaunchDarkly provides SDKs for various languages, frameworks, and platforms that not only connect applications to its API but also offer additional functionality such as streaming flag changes and local caching of flag values. While the SDKs are straightforward to use, developers may prefer creating custom wrappers around the API provided by the SDK for reasons like encapsulating all SDK-specific interaction in a single library, simplifying SDK usage, preventing accidental bugs, or adding domain-specific business logic around flag usage. The example code on GitHub demonstrates how to create such wrappers using Node.js Express project with wrappers for both the frontend browser client and the backend Node server environment.