Rank #05 · Daily · Infra
floci: Free Local AWS Emulator (LocalStack Alternative)
Point your AWS SDK, CLI, Terraform, or tests at http://localhost:4566 and keep working offline — no LocalStack auth token required.
What it does
Floci is a free, open-source local AWS emulator. Per the README:
- Start with the CLI (
floci start) ordocker composeusingfloci/floci:latest. Standalonefloci-awsbinaries ship for Linux, macOS, and Windows. - Existing AWS clients keep working: set
AWS_ENDPOINT_URL=http://localhost:4566(oreval $(floci env)). - Claims drop-in LocalStack replacement: swap the image and keep going.
- Services that need fidelity (Lambda, RDS, ECS, EC2, EKS, ElastiCache, and others listed in the README) use real Docker-backed execution rather than shallow mocks.
- Optional web console at
http://localhost:4566/_floci/ui(sidecar container; Docker socket required). - Configurable persistence (in-memory, persistent, hybrid, WAL).
- Part of a multi-cloud family (floci-az / floci-gcp / floci-oci on other ports); this repo is the AWS member.
The README positions Floci against LocalStack Community after LocalStack's community edition sunset (March 2026), which introduced auth tokens and froze security updates for that edition. Treat the project's own startup-time / memory / image-size comparison table as vendor-reported — TidyHow hasn't reproduced those numbers.
Who it's for
Backend and platform engineers who need AWS-shaped services in local or CI environments without cloud accounts or paid emulator gates; teams migrating off LocalStack Community; anyone running Terraform/CDK/OpenTofu or Testcontainers against a local endpoint.
Stars / language / license
28,791 stars · Java · MIT
Data verified: 2026-11-04 09:13 Asia/Shanghai (GitHub API get_repository + README get_file_contents)
Trending note: +482 stars today (Trending selection captured 09:12 Asia/Shanghai)
Category tags
Infra · AWS · local-emulator · DevOps · Docker · Java · CI
How it differs from similar projects
LocalStack. Closest peer. Floci markets itself as always-free MIT with no auth token, and as a drop-in on port 4566. LocalStack's product split (community vs paid) and post-sunset community terms are the contrast the README emphasizes. Service coverage and API fidelity still need verification against your own workloads.
Moto. Great for unit-level Python mocking; not a full multi-service HTTP endpoint for arbitrary SDKs and IaC.
Real AWS accounts / LocalZones. Highest fidelity, but cost, credentials, and network dependency.
Emulators approximate AWS. Validate the services you depend on before treating Floci as production-parity.