Develop serverless WebAssembly apps with Spin

Create, build, test, and deploy an app in just a few minutes.

Spin is the developer tool for building WebAssembly microservices and web applications

Do more, faster. Pick your favorite language and dive into the important part using Spin's serverless framework. Connect your application to Redis, PostgreSQL, and other data services. And skip the boilerplate.

Choose your language

Spin SDKs are available in Python, Go, JavaScript, Rust, Go and .NET. And all WASI-compatible languages are supported.

Spin SDKs are available in Rust, Go and .NET. And all WASI-compatible languages are supported.

Three commands are all you need

Keep the development loop simple. Create a project with 'spin new'. Build it with 'spin build'. And test it locally with 'spin up'.

See it in action on the Cloud

Ready for production? Pushing to the Fermyon Cloud is only a 'spin deploy' away.

Build full-stack applications

New

Serverless AI

Execute inferencing for LLMs directly from serverless apps.

SQLite Databases

Spin has a built-in database, which is always available - no Ops required.

Key/Value Store

Quickly persist data in your apps with Spin's in-built local KV store.

HTTP & Redis Triggers

Spin has a built-in HTTP web server and pub-sub Redis triggers, routing requests and messages to components.

Relational Database Storage

'Bring your own DB' support for MySQL and PostgreSQL, where you host and manage the database outside of Spin.

Variables & Secrets

Dynamic app variables mean a simpler experience for rotating secrets, updating API endpoints, and more.

frictionless developer experience

Powerful CLI

Start, run and deploy projects with ease. Blinking cursor to deployed app in 66 seconds.

Languages & SDKs

Spin works with many, many different languages. all WASI-compatible languages are supported.

Local Dev

In-built commands like spin watch and spin doctor simplify the writing and debugging of apps.

Powered by WebAssembly

WebAssembly

Run event-driven Wasm services and web applications.

Secure by Default

Ensure clear separation of services with sandboxing.

Open Source

Open Source code written by long-time OSS contributors.

Be among the first to discover tomorrow's technology

Spin on GitHub Install Spin

PRODUCTS & PROJECTS

From blinking cusor to deployed app in less than two minutes

Fermyon Cloud is the easiest way to deploy and manage native WebAssembly applications

Learn More

A micro-CMS for WebAssembly and Spin

Compiled to WebAssembly, Bartholomew can run in any Spin environment.

GitHub Repo

Why Fermyon?

The next wave of cloud compute looks like this

Architected to compile and ship your code as Wasm binaries, Fermyon is a lighter, faster and truly serverless cloud. No need to deal with images, OS layers or instance config.

Finally the promise of true sustainable serverless cloud computing is here with Fermyon’s Cloud offering — a platform that allows me to use almost any language, is incredibly easy to use and blazingly fast.”

— Federico Dionisi

typical app image
200MB+

app.wasm
3.2MB

Hello
supersonic.

Goodbye
cold starts.

0ms 50ms 100ms 150ms 200ms 250ms

Data source. Learn more.

Automatically scales-to-zero

Requests are so fast, services can shut back down seamlessly between requests — minimizing compute consumption.

Secure by
default

Every Wasm application runs in a secure sandbox — eliminating cross contamination.

Compute less, save more

A lighter, faster, and more efficient model means lower cost and more sustainable for your business and our planet.

We've got you covered.

Not just JavaScript — compile almost any language to Wasm.

Rust, Go, Python, JavaScript, .NET, Ruby, C#

Fermyon’s Spin works with mainstream languages like JS/TS, Python, .NET, Rust, and Go. We adhere to the WASI standard, which means dozens of languages that have support for Wasm can be compiled, built and deployed.

Quotes

“We've been able to take a Kubernetes batch process of tens of thousands of orders and cut the compute cost by 60%, without trading off performance”

Kai Walter

Distinguished Architect, ZEISS Group

“It enabled us to build holistic service components, including smart contracts, and integrated a zero trust architecture with confidence that third-party code wouldn't introduce risk in such a critical environment”

PJ Łaszkowicz

Technical Director, Omnijar

“Fermyon not only reduces complexity but also continues to address enterprise cloud computing pain points head-on while also considering the growing demand for increased profitability and productivity.”

Paul Nashawaty

Principal Analyst at The Futurum Group

“It took me 13 lines of code and 2 commands (spin build, spin cloud deploy) to build and deploy a simple 'chatGPT like' app with Fermyon”

Sébastien Blanc

Aiven.io

“I'm getting some hands on time with WebAssembly by playing around with Fermyon and their Spin framework. I think it's extra dope.”

Kelsey Hightower

Former Distinguished Engineer, Google

Deploy and run for free

No tricks. You can run apps on Fermyon Cloud without having to worry about an expiration date. You can opt into future, paid upgrades later on if you need to.

Read the Docs