WasmCloud Has a Free API: Build Distributed Apps With WebAssembly Components

What if your microservices were WebAssembly components that could run anywhere — edge, cloud, IoT — and swap providers without code changes?

What Is WasmCloud?

WasmCloud is a platform for building distributed applications using WebAssembly components. Instead of Docker containers with fat runtimes, you build tiny Wasm components that connect to capabilities (HTTP, messaging, key-value, etc.) through a contract system.

// A simple HTTP handler component
use wasmcloud_interface_httpserver::*;

#[async_trait]
impl HttpServer for MyActor {
    async fn handle_request(&self, ctx: &Context, req: &HttpRequest) -> HttpResponse {
        HttpResponse {
            status_code: 200,
            header: Default::default(),
            body: b"Hello from WasmCloud!".to_vec(),
        }
    }
}

The Architecture

Application = Components + Providers + Links

Component: Your business logic (Wasm)
Provider: Infrastructure capability (HTTP server, Redis, NATS, S3, etc.)
Link: Runtime connection between component and provider

Your component says "I need key-value storage." At deploy time, you link it to Redis, DynamoDB, or a local file — without changing code.

Why WasmCloud

1. Swap infrastructure without code changes:

# Dev: link to local Redis
- component: my-app
  provider: redis-local

# Prod: link to AWS DynamoDB
- component: my-app  # SAME component!
  provider: dynamodb-provider

2. Tiny binaries — Components are kilobytes, not gigabytes.

3. Portable — Run anywhere WASI works: cloud, edge, IoT, your laptop.

4. Secure — Wasm sandbox + capability-based security. Components can't access anything not explicitly linked.

5. Distributed — Components auto-schedule across a mesh of hosts. Scale horizontally by adding hosts.

CNCF Project

WasmCloud is a CNCF Sandbox project. It's not a side project — it's the future of cloud-native applications.

wash up  # Start a WasmCloud host
wash app deploy wadm.yaml  # Deploy your application

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Building distributed Wasm apps? Check out my developer tools or email [e-mail].