Floci is a free and open source tool that runs versions of AWS services on your computer. It supports services such as S3, DynamoDB, SQS, and Lambda, and works with familiar AWS tools and software libraries. Some services use Docker containers for more realistic behavior. Floci is useful for developing and testing cloud applications, including in automated test pipelines, without an AWS account or authentication token. It also offers a browser console for checking local resources and options to save or discard data between runs.