Local AWS cloud emulator for integration tests. Run your app with normal AWS clients, stay fully local, and use fakecloud SDKs when your tests need deeper visibility.
105 services. 7,508 operations. 248,557/248,557 Smithy variants pass — true 100% conformance.
fakecloud gives you a local AWS environment that behaves like infrastructure, not a mock. Your app uses the regular AWS SDK, CLI, and IaC tools. Unlike today's LocalStack Community setup, you do not need an account, auth token, or paid plan just to keep core development flows local.
The SDKs make that workflow nicer, not narrower. Start fakecloud, run the code you actually ship, inspect emails/messages/invocations after the fact, and force async AWS-style behavior to happen on demand.
Real APIs for your app, purpose-built tooling for your tests.
Workflow
Use normal AWS clients against localhost, then verify the effects with fakecloud instead of stitching together polling, fixtures, or private test hooks.
SDKs
TypeScript, Python, Go, PHP, Java, and Rust SDKs wrap the /_fakecloud/* endpoints for resets, assertions, and manual control of async processors after your app has already used the normal AWS APIs.
Coverage
S3, SQS, SNS, EventBridge, EventBridge Pipes, EventBridge Scheduler, Lambda, EC2, DynamoDB, IAM, STS, Organizations, SSM, Secrets Manager, CloudWatch Logs, CloudWatch (Metrics & Alarms), KMS, CloudFormation, Cloud Control API, SES, Cognito User Pools, Cognito Identity, Kinesis, Firehose, RDS, RDS Data API, Aurora DSQL, Resource Groups, Resource Groups Tagging API, ElastiCache, MemoryDB, EKS, Cloud Map, Step Functions, API Gateway v1 (REST), API Gateway v2 (HTTP), Bedrock, Bedrock Agent, Bedrock Agent Runtime, Bedrock Runtime, ECR, ECS, Elastic Load Balancing v2, CloudFront, Route 53, WAF v2, Application Auto Scaling, Athena, ACM, and Glue.
Tested
True 100% conformance across all 3,932 implemented API operations: 248,557/248,557 Smithy-model-generated test variants pass on every commit, backed by end-to-end tests against the official AWS SDKs.
Real behavior
30+ service-to-service integrations: S3 notifications, SNS fanout, EventBridge targets, DynamoDB Streams, CloudWatch Logs subscriptions, Cognito triggers, Step Functions task integrations, API Gateway → Lambda, and more — all exercise real service interactions.
Simple
Run a single binary or Docker image, use any dummy credentials, and keep the whole workflow local without signing in to someone else's platform.
Keep using the AWS SDK in your app. Use fakecloud SDKs when your tests need visibility and control on top of the emulator itself.
TypeScript
npm install fakecloudInspect SES emails, SNS messages, SQS queues, Lambda invocations, Cognito confirmation codes, and more.
Python
pip install fakecloudAsync and sync clients for pytest or app-level integration tests, with the same introspection and simulation coverage.
Go
go get github.com/faiscadev/fakecloud/sdks/goContext-friendly helpers for resets, event history, SES inbound simulation, and the rest of the fakecloud test surface.
Rust
cargo add fakecloud-sdkNative Rust client for tests that need resets, state inspection, and direct access to the fakecloud introspection surface.
Start fakecloud, point your AWS client at localhost, then assert what happened.
If you want a fully local workflow with real AWS APIs and no account requirement, fakecloud is built for that path. The SDKs are an extra testing advantage, not a replacement for that positioning.
| fakecloud | LocalStack Community | |
|---|---|---|
| License | AGPL-3.0 | Proprietary |
| Auth required | No | Yes (account + token) |
| Commercial use | Free | Paid plans only |
| Docker required | No (standalone binary) | Yes |
| Startup time | ~300ms | ~3s |
| Idle memory | ~10 MiB | ~150 MiB |
| Install size | ~19 MB binary | ~1 GB Docker image |
| AWS services | 46 at true 100% conformance | 30+ (paid-only past Community) |
| Test assertion SDKs | TypeScript, Python, Go, PHP, Java, Rust | Python, Java |
| Cognito User Pools | 122 operations | Paid only |
| SES v2 | 110 operations | Paid only |
| SES inbound email | Real receipt rule actions | Stored but never executed |
| RDS | 163 operations, PostgreSQL/MySQL/MariaDB via Docker, PostgreSQL aws_lambda extension | Paid only |
| ElastiCache | 75 operations, Redis and Valkey via Docker | Paid only |
| MemoryDB | 45 operations, full control plane | Paid only |
| EKS | Cluster control plane (batch 1) | Paid only |
| API Gateway v2 | 103 operations, HTTP APIs + developer portals + JWT/Lambda authorizers | Paid only |
| Bedrock | 214 operations across 4 APIs (Bedrock + Bedrock Runtime + Bedrock Agent + Bedrock Agent Runtime) | Not available |
Every implemented API is covered by conformance and behavioral testing, with the service mix tuned for local development and integration tests.
EventBridge Scheduler
JSON protocol
Lambda
REST protocol · JSON
Secrets Manager
JSON protocol
CloudWatch Logs
JSON protocol
CloudFormation
Query protocol
Cognito User Pools
JSON protocol
ElastiCache
Query protocol
MemoryDB
JSON 1.1 protocol
Step Functions
JSON protocol
API Gateway v1 (REST)
REST protocol · JSON
API Gateway v2
REST protocol · JSON
Bedrock
REST protocol · JSON
Bedrock Runtime
REST protocol · JSON
Bedrock Agent
REST protocol · JSON
Bedrock Agent Runtime
REST protocol · JSON
Elastic Load Balancing v2
Query protocol
CloudFront
REST protocol · XML
Route 53
REST protocol · XML
Application Auto Scaling
JSON protocol
Cognito Identity
JSON protocol
CloudWatch (Metrics & Alarms)
Query protocol
Organizations
JSON protocol
Cloud Control API
JSON protocol
EventBridge Pipes
REST protocol · JSON
RDS Data API
REST protocol · JSON
Aurora DSQL
REST protocol · JSON
Resource Groups
REST protocol · JSON
Resource Groups Tagging API
JSON protocol