Amplify Storage Simulator

Amplify Storage Simulator (v1.11.8) is an S3 API simulator designed for local testing of AWS Amplify projects that use S3 storage. It implements a subset of S3 REST APIs (ListObjects, GetObject, PutObject, DeleteObject, etc.) using a local file system backend, enabling offline development without actual AWS credentials. Part of the AWS Amplify CLI monorepo, it is updated irregularly alongside Amplify CLI releases. Unlike mock AWS services such as localstack or moto, it is lightweight, Amplify-specific, and integrates seamlessly with Amplify's storage category. It ships TypeScript types and is ESM-only. Key differentiators: automatic Amplify resource path mapping, no Docker dependency, and direct integration with Amplify's local mock server.