An application communicates with multiple third-party services that use API keys. When stress testing the system, developers must change the URLs of the third-party services. The application must run

Secrets are designed for sensitive information requiring secure storage and access, not for general configuration values like dynamic URLs or port numbers that are frequently changed during testing.

Sane defaults provide initial reasonable values but do not offer the dynamic, runtime flexibility needed to change critical configurations such as service URLs or ports easily.

Application parameters, often implemented as environment variables or configuration files, allow for externalizing configurable values like service URLs, port numbers, and API keys from the application's codebase. This approach enables developers to modify these settings easily at runtime without the need to recompile or redeploy the application, which is particularly beneficial during development and stress testing scenarios requiring dynamic configuration changes.

Config maps are a Kubernetes-specific resource for storing non-sensitive configuration data and represent a specific implementation of externalized configuration, whereas 'application parameters' is a broader, more fundamental concept covering this requirement.