Floci – A free, open-source local AWS emulator

Named after floccus — the cloud formation that looks exactly like popcorn.

A free, open-source local AWS emulator. No account. No feature gates. No CI restrictions. Just docker compose up.

LocalStack's community edition sunset in March 2026 — requiring auth tokens, dropping CI support, and freezing security updates. Floci is the no-strings-attached alternative.

| Floci | LocalStack Community | | |---|---|---| | Auth token required | No | Yes (since March 2026) | | CI/CD support | Unlimited | Requires paid plan | | Security updates | Yes | Frozen | | Startup time | ~24 ms | ~3.3 s | | Idle memory | ~13 MiB | ~143 MiB | | Docker image size | ~90 MB | ~1.0 GB | | License | MIT | Restricted | | API Gateway v2 / HTTP API | ✅ | ❌ | | Cognito | ✅ | ❌ | | ElastiCache (Redis + IAM auth) | ✅ | ❌ | | RDS (PostgreSQL + MySQL + IAM auth) | ✅ | ❌ | | S3 Object Lock (COMPLIANCE / GOVERNANCE) | ✅ | | | DynamoDB Streams | ✅ | | | IAM (users, roles, policies, groups) | ✅ | | | STS (all 7 operations) | ✅ | | | Kinesis (streams, shards, fan-out) | ✅ | | | KMS (sign, verify, re-encrypt) | ✅ | | | Native binary | ✅ ~40 MB | ❌ |

20+ services. 408/408 SDK tests passing. Free forever.

# docker-compose.yml
services:
  floci:
    image: hectorvent/floci:latest
    ports:
      - "4566:4566"
    volumes:
      - ./data:/app/data

docker compose up

All services are available at http://localhost:4566. Use any AWS region — credentials can be anything.

export AWS_ENDPOINT_URL=http://localhost:4566
export AWS_DEFAULT_REGION=us-east-1
export AWS_ACCESS_KEY_ID=test
export AWS_SECRET_ACCESS_KEY=test
# Try it
aws s3 mb s3://my-bucket
aws sqs create-queue --queue-name my-queue
aws dynamodb list-tables

Point your existing AWS SDK at http://localhost:4566 — no other changes needed.

// Java (AWS SDK v2)
DynamoDbClient client = DynamoDbClient.builder()
    .endpointOverride(URI.create("http://localhost:4566"))
    .region(Region.US_EAST_1)
    .credentialsProvider(StaticCredentialsProvider.create(
        AwsBasicCredentials.create("test", "test")))
    .build();

# Python (boto3)
import boto3
client = boto3.client("s3",
    endpoint_url="http://localhost:4566",
    region_name="us-east-1",
    aws_access_key_id="test",
    aws_secret_access_key="test")

// Node.js (AWS SDK v3)
import { S3Client } from "@aws-sdk/client-s3";
const client = new S3Client({
    endpoint: "http://localhost:4566",
    region: "us-east-1",
    credentials: { accessKeyId: "test", secretAccessKey: "test" },
    forcePathStyle: true,
});

| Tag | Description | |---|---| | latest | Native image — sub-second startup (recommended) | | latest-jvm | JVM image — broadest platform compatibility | | x.y.z / x.y.z-jvm | Pinned releases |

All settings are overridable via environment variables (FLOCI_ prefix).

| Variable | Default | Description | |---|---|---| | QUARKUS_HTTP_PORT | 4566 | HTTP port | | FLOCI_DEFAULT_REGION | us-east-1 | Default AWS region | | FLOCI_DEFAULT_ACCOUNT_ID | 000000000000 | Default AWS account ID | | FLOCI_STORAGE_MODE | hybrid | memory · persistent · hybrid · wal | | FLOCI_STORAGE_PERSISTENT_PATH | ./data | Data directory |

MIT — use it however you want.