Introducing cloudemu#

We're excited to announce cloudemu — a zero-cost emulator for AWS, Azure, and GCP cloud services, entirely in memory. Point the real cloud SDKs at it — in-process, as a standalone server, or in Docker — from any language.

The Problem#

Every team that builds on cloud services faces the same testing dilemma:

1. Use real cloud accounts — expensive, slow, requires network access
2. Use Docker-based emulators — complex setup, moderate speed, heavy on resources
3. Write custom mocks — tedious, incomplete, hard to maintain

None of these options give you fast, realistic, and free cloud testing.

The Solution#

cloudemu provides 48 in-memory service implementations (16 categories across AWS, Azure, and GCP) that behave like the real thing:

aws := cloudemu.NewAWS()

// This works exactly like real EC2
instances, _ := aws.EC2.RunInstances(ctx, config, 3)

No cloud accounts. No bills. In-process tests run in ~10ms.

What Makes It Different#

cloudemu goes beyond basic CRUD mocks:

• State machines enforce valid lifecycle transitions
• Auto-metrics are emitted to the monitoring service
• FIFO deduplication with 5-minute windows
• Dead-letter queues for messages exceeding max receive count
• TTL expiry with lazy cleanup on read
• IAM policy evaluation with wildcard matching

Get Started#

go get github.com/stackshy/cloudemu

Check out the Quick Start guide to build your first cloud simulation in 5 minutes.