AWS AppConfig

What AWS AppConfig is

AWS AppConfig is a configuration service for changing application behavior while software is running in production. Teams can use feature flags and dynamic configuration to release a feature immediately or roll it out gradually to selected user groups, including fine-grained and high-cardinality segments. AppConfig also supports A/B and multivariate experiments on live traffic, covering feature flags, configuration values, and user experiences. Teams can manage LLM model settings, parameters, and prompts as dynamic configuration and test variations with live traffic.

Configuration data can be deployed from AppConfig’s hosted store, AWS Secrets Manager, Systems Manager Parameter Store, or Amazon S3. Deployments can be started from the AWS Management Console, AWS CLI, or an SDK. AppConfig supports workloads on EC2 instances, AWS Lambda containers, mobile applications, and edge devices. Monitored alarms can trigger rollback when they cross predefined thresholds; named integrations include Amazon CloudWatch, Datadog, and Dynatrace. AWS-authored extensions can send deployment events to EventBridge, SNS, or SQS, and create or update Atlassian Jira issues when feature flags change. PrivateLink provides private VPC access, and customer-managed AWS KMS keys add encryption for hosted and deployed configuration data. The hosted configuration store defaults to a 2 MB size limit, with a 4 MB maximum.

Who it suits

AWS AppConfig suits teams that need to adjust production behavior with feature flags or runtime configuration, or gradually release changes to selected user groups. It can also fit teams running experiments or managing LLM settings as configuration across supported AWS-hosted, mobile, and edge workloads.

Limits

The hosted configuration store has a 2 MB default configuration size limit and a 4 MB maximum. The listed plan is billed by usage: $0.0000002 per configuration request, $0.0008 per configuration received, and $0.90 per experiment hour.

Getting started

1. Open the AWS AppConfig website.
2. Choose the hosted store, Secrets Manager, Systems Manager Parameter Store, or Amazon S3 as a configuration source.
3. Use the AWS Management Console, AWS CLI, or an SDK to start a deployment.
4. Connect the deployment to a supported workload, such as an EC2, Lambda container, mobile, or edge application.

Verdict

Choose AWS AppConfig if your team needs to change production configuration, roll out features gradually, or run live traffic experiments. Its usage-based plan charges for configuration requests, configuration received, and experiment hours, and hosted configurations have a 4 MB maximum.