apolloconfig/apollo

Apollo is a configuration management system designed for software teams that run many different services or applications and need a reliable way to manage the settings those applications use. Instead of storing configuration values (database addresses, feature flags, timeouts, etc.) inside the application code or on individual servers, Apollo provides a central web interface where configurations can be edited, versioned, and pushed out to running applications in real time, typically within one second of publishing a change. It is particularly suited to microservice architectures, where many small services run independently and may be deployed in different environments (development, staging, production) or across multiple server clusters. Apollo lets you manage configurations separately for each environment and cluster through one unified interface, without touching the code itself. Key capabilities include: real-time configuration updates without restarting applications, version history with easy rollback, gradual (grayscale) rollout of changes to only a subset of instances before applying them everywhere, full audit logs, and access controls separating who can edit versus publish configurations. Client libraries are available for Java.Net, Go, Python, Node.js, PHP, and others. Deployment requires only Java and MySQL. Someone would use Apollo when they have multiple applications or services whose settings change frequently and they want a safe, auditable, centralized way to manage those changes without redeploying code.