Fakecloud Offers a Free AGPL AWS Emulator After LocalStack Added Auth

Fakecloud, a free AWS emulator released under AGPL-3.0-or-later, says it covers 105 services and 7,509 operations in a single binary that needs no account. The repository, which showed 708 stars and 47 forks when The Terminal read it, positions itself as the alternative to LocalStack, the emulator that put its own AWS product behind authentication in March 2026.

Every capability figure in this piece is the project's own. The Terminal did not install fakecloud or run its tests.

What LocalStack changed

In a post dated Dec. 18, 2025 and updated March 17, 2026, LocalStack co-CEO and CTO Waldemar Hummer and co-CEO and COO Gerta Sheganaku announced that its separate Community and Pro images would merge into one. Running the latest version would require an account. The post says the source code for prior Community versions "will remain openly available on GitHub", while the repository moves to reduced maintenance.

The free tier matters most for the people fakecloud is aimed at. It offers equivalent capability to the old Community image but excludes CI credits, so continuous-integration runs need a paid plan. A later pricing update restricted the free tier to non-commercial use.

What fakecloud claims

The README lists these figures for its own emulator, none independently checked:

Claim	Figure in the README
AWS services	105
Operations	7,509
Smithy conformance	248,557 variants passing, "true 100%"
Binary size	about 19 MB
Idle memory	about 10 MiB
Startup	about 300 ms
Licence	AGPL-3.0-or-later

Smithy is the interface definition format AWS uses to describe its APIs, so a conformance figure measures agreement with those definitions. It says less about whether a Lambda function or an RDS instance behaves as it does in a real account. The README says stateful services such as Lambda, RDS with six engines and ElastiCache run on real infrastructure, and that events cross services, for example EventBridge to Step Functions and S3 to Lambda.

What the licence means for a test tool

AGPL-3.0-or-later is a copyleft licence that extends source-sharing duties to people who let others use a modified version over a network. For a team that runs the unmodified binary in CI, that rarely bites. For a vendor that wants to embed and modify it inside a hosted product, it does. The README does not say which of those cases the author has in mind.

The project also ships first-party test SDKs for TypeScript, Python, Go, PHP, Java, Rust and .NET, an optional SigV4 and IAM enforcement mode, and a Bedrock emulator with 216 operations. Applications point their AWS SDK at http://localhost:4566.

What to check before switching

We have written before about maintainer risk in fast-rising open-source projects, in our Paperclip piece and our Hindsight piece. Stars measure attention, not adoption.

The concrete test is to run your own integration suite against both emulators and diff the failures. The number to watch is how many of your services sit in fakecloud's 105 and behave as they do against AWS itself, because the README's 248,557 passing variants cannot answer that for you.