This is a feature flag / dynamic configuration requirement: enable a new feature for a subset of users (premium customers), toggle it on/off quickly based on feedback/performance, and deploy configuration changes safely with validation and without disruption. AWS AppConfig (part of AWS Systems Manager) is designed for exactly this use case.
AWS AppConfig helps create, manage, and deploy application configurations, including feature flags, in a controlled way. It supports configuration validators (such as JSON schema or Lambda validators) to catch errors before deployment. It also supports controlled rollouts with deployment strategies to reduce blast radius (for example, gradual deployments). This allows rapid changes without redeploying code and minimizes disruption.
Option A aligns perfectly: use AppConfig feature flags to target premium users and toggle the feature quickly.
Option B is incorrect because Secrets Manager is for sensitive secrets (passwords, API keys), not feature flag management and progressive configuration deployments.
Option C is incorrect because AWS Config evaluates resource compliance and records configuration changes of AWS resources; it does not serve runtime feature flag delivery.
Option D (Parameter Store) can store configuration values, but it does not provide the same feature-flag-focused capabilities, validation/deployment strategies, and safe rollout controls that AppConfig provides. Also, “lifecycle rules” is not how Parameter Store toggles features.