Amazon Web Services said AWS Emulator is now available for building and testing AWS applications on a computer or in a continuous-integration environment, with no deployments or AWS account required, according to an official what’s-new notice.
Existing AWS SDK and CLI calls go to the emulator and come back in milliseconds, AWS said, signed with credentials the emulator provides. For supported operations, it returns the same result as AWS for valid calls and the same errors for invalid ones; unsupported operations return 501 Not Implemented. Resource state is kept in memory until the process stops. Each copy gets its own port, keys and in-memory state, so agents, test suites and CI jobs do not see one another’s resources. AWS gave the example of a coding agent creating a DynamoDB table, testing against it offline, and fixing code before a deploy.
Services in the emulator are generated from the same API models AWS publishes for its SDKs, the company said; when AWS adds a service or API, it shows up in the emulator, with behavior filled in and verified release by release. A fidelity report compares responses to AWS. The emulator does not depend on an AWS Region, has no additional service fee — customers pay only for resources when they deploy to AWS — and its source code is published under the CC0 1.0 Universal public-domain dedication, the notice said.