By deploying feature flags and configuration changes at runtime, software behavior to be adjusted immediately or gradually without the risk of redeploying a new version of code. When you use AWS AppConfig, your teams can be responsive, turn features on or off, or throttle up or down other configurations in real time, without restarting your app in production. This process is called “continuous configuration."

With AWS AppConfig’s advanced targeting capabilities, you can enable or experiment with limited cohorts of users before rolling out features to all users. You can set up multiple values within flag data, and target those values to fine-grained and high-cardinality user segments.

AWS AppConfig supports best practices by rolling out configuration changes instantly or gradually. The configuration change is monitored over a time period that customers define. If you configure alarms in Amazon CloudWatch, AppConfig can automatically rollback configuration changes in the event that those alarms are triggered.

Many customers use AWS AppConfig to safely release new features. A feature can be released on production, but hidden behind a feature flag, inaccessible to users. When the feature is ready to be released, deploying a small configuration update with AWS AppConfig can “turn on” that feature for users. Features can be released to some or all users, instantly or gradually with multiple values within flag data, allowing customers to target those values to fine-grained and high-cardinality user segments.

AWS AppConfig can be used to adjust ops behavior at runtime.  For example, you may put timeout values into configuration data, and want to update those on the fly to best tune application performance. Similarly, a DevOps engineer may want to adjust logging verbosity, and increase what events are recorded during a suspected security incident, all without re-deploying the full app. 

Certain functionality, APIs, or types of data may only be available to specific users for your app. This can be managed through a dynamic allow-list. Conversely, you may want to block access to specific data or features, and this would be managed through a block-list. AWS AppConfig enables quick and safe management of these lists that gate access.