Floci AWS Local Emulator on Ubuntu 24.04

A free self-hosted AWS local emulator

Floci is a free, open source, MIT licensed local AWS emulator, a self hosted alternative to LocalStack. It gives you AWS shaped services on a single virtual machine without a cloud account, an auth token, or paid feature gates. Point your AWS SDK, CLI, Terraform, CDK, OpenTofu or test suite at the emulator and keep your existing workflows, so teams can develop against AWS APIs and run continuous integration without spending on real cloud resources or per developer licences.

Around 69 AWS services on one VM

Floci speaks the AWS wire protocol on port 4566 and emulates S3, SQS, SNS, EC2, ECS, Lambda, RDS, DynamoDB, ElastiCache, OpenSearch, IAM, API Gateway and around 69 AWS services in total, using real Docker backed execution for the services that need it rather than shallow mocks. It is a Quarkus native binary, so it starts in milliseconds and idles at tens of MiB of memory, comfortably within the recommended Standard_B2s. Docker Engine and the AWS CLI v2 are preinstalled, so the emulator can be exercised the moment you connect.

Secure by default

Floci is auth less by design, which is correct for a local development tool but dangerous as an open service on a public address, since an open AWS emulator is a service abuse and compute consumption surface. This image inverts that default. The emulator port 4566 is shipped closed in the network security group, so only SSH is open and a fresh appliance never exposes an unauthenticated AWS emulator to the internet. Reach the emulator over an SSH tunnel, so it is only ever reachable from your own machine, or open port 4566 in the network security group restricted to your own source addresses, behind your own controls. Floci is a fake AWS: it holds no real cloud credentials and accepts any non empty key and secret, so there is no dashboard, no admin account and no default password baked into the image, and therefore nothing to leak and nothing to seize.

What you get

• Floci 1.6.0, the official upstream container pinned by image digest and captured into the image, so first boot is instant with no pull
• The emulator managed by one systemd service that starts on boot, with an explicit memory bound so it never thrashes the VM
• Emulation of S3, SQS, EC2, ECS, Lambda, RDS, DynamoDB, ElastiCache, OpenSearch and around 69 AWS services on port 4566
• Docker Engine and the AWS CLI v2 preinstalled, so the emulator can be exercised the moment you connect
• A clean, empty emulator on first boot with no baked data and no default login
• Unattended security upgrades left enabled, and 24/7 cloudimg support

Licensing

Floci is distributed under the MIT License, permissive and free to redistribute, and the licence text ships on the image unmodified. The cloudimg charge ($0.04 per vCPU/hour) covers packaging, security patching, image maintenance and 24/7 expert support.

Amazon S3, DynamoDB and AWS are trademarks of Amazon.com, Inc. or its affiliates. cloudimg is not affiliated with, endorsed by, or sponsored by the Floci project or Amazon.