How does ConfigCat work?

The ConfigCat SDK polls the CDN for the latest feature flag and setting values repeatedly and caches them. When a feature flag value is requested by our customer's application the SDK evaluates feature flag values locally on the client side and returns them. This way no data leaves the client application even if the feature flag values depend on sensitive user info. In case of no internet connection a customer provided default value will be returned, making sure the application runs smoothly.

Architecture diagram of ConfigCat

Management Console

Graphical user interface (GUI) even for non-technical people to easily manage Configs, Feature Flags and Settings, invite team mates, add/remove Group Permissions or view the Audit Log.

ConfigCat API

Serves the Management Console with data. Provides an interface for creating and updating Feature Flags. Runs the business logic and keeps CDN Servers consistent with the Database.

CDN Servers

Serving our customers' JSON configuration files containing Feature Flags, Settings and their values. Designed to scale quickly and to handle a massive number of requests.

ConfigCat SDKs

Responsible for downloading and caching the JSON configuration files. Also providing an interface to access Feature Flag and Setting values simply from any Desktop, Mobile, Frontend or Backend application. All the SDKs are open source on GitHub.