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Softlaunch SDKs load your configuration snapshot and evaluate flags locally. Pick the SDK that matches where your code runs.

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Client vs. server

Client SDKs

Run in browsers, mobile apps, and other public clients. Use a client key (slc_), which serves an obfuscated configuration.

Server SDKs

Run in trusted backends. Use a server key (sls_), which reads the full configuration. Keep it secret.

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Available SDKs

React

@softlaunch/react — a provider and hooks for React apps.

JavaScript

@softlaunch/js — a client for any JavaScript runtime.
More SDKs are on the way:

Node.js

Coming soon

Go

Coming soon

Python

Coming soon

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A shared API

Every SDK exposes one typed accessor per flag type. The arguments are the same everywhere: 
get<Type>Flag(flagKey, subjectKey, attributes, defaultValue);
ArgumentDescription
flagKeyThe key of the flag to evaluate.
subjectKeyA stable identifier for the user or entity.
attributesKey–value attributes used for targeting.
defaultValueReturned while loading, or if the flag is missing or mistyped.
The typed accessors are getBooleanFlag, getStringFlag, getIntegerFlag, getNumericFlag, and getJsonFlag (the React SDK exposes the same set as hooks: useBooleanFlag, and so on).
SDKs stay subscribed after the first load. When you change a flag, connected SDKs receive the update in real time and re-evaluate.