@virke/wasm-component

Wasm Component Model support for Virke applications.

Overview

This package enables building Virke applications using the Wasm Component Model, a portable binary interface standard for WebAssembly. Component Model applications are more portable, composable, and future-proof than traditional Wasm modules.

Features

• Type-safe runtime bindings for Virke services (KV, DB, OS3, logging)
• Standard HTTP interface via wasi:http/incoming-handler
• Componentization tooling powered by componentize-js
• WIT definitions for the Virke world

Installation

bun add @virke/wasm-component

Usage

Basic Handler

import { defineHandler, json } from "@virke/wasm-component";

export default defineHandler(async (request) => {
  return json({ message: "Hello from Wasm Component Model!" });
});

Using Virke Runtime Services

import { defineHandler, json, kv, db, os3, logging } from "@virke/wasm-component";

export default defineHandler(async (request) => {
  // KV Store
  const value = kv.get("my-key");
  const setResult = kv.set("my-key", "my-value", 3600);

  // Database
  const queryResult = db.query("SELECT * FROM users WHERE id = ?", ["123"]);

  // Object Storage
  const getResult = os3.get("files/document.pdf");

  // Logging
  logging.log("info", "Request processed");

  return json({ value, queryResult });
});

Componentization

The componentization happens automatically during deployment via the Virke CLI. The CLI detects Component Model projects and uses componentize-js to build them.

Project Setup

Add to your virke.toml:

[project]
name = "my-component-app"
type = "component"

[compute]
entry = "src/handler.ts"

WIT Interface

The Virke runtime provides these interfaces:

• virke:runtime/kv - Key-value store
• virke:runtime/db - SQL database
• virke:runtime/os3 - Object storage
• virke:runtime/logging - Structured logging

Your component exports:

• wasi:http/[email protected] - HTTP request handler

Deployment

virke deploy

The CLI will:

1. Detect the type = "component" configuration
2. Bundle your TypeScript/JavaScript code
3. Run componentize-js to generate a Wasm component
4. Upload the component to Fastly Compute@Edge

Architecture

Component Model applications on Virke run as dedicated Fastly Compute services. The Virke runtime provides host implementations of the imported interfaces (KV, DB, OS3, logging) using Fastly's native services.

┌─────────────────────────────────────┐
│   Your Component (Wasm)             │
│                                     │
│   import virke:runtime/kv           │
│   import virke:runtime/db           │
│   export wasi:http/incoming-handler │
└─────────────────────────────────────┘
              ↓
┌─────────────────────────────────────┐
│   Virke Runtime (Fastly C@E)        │
│                                     │
│   - KV Store bindings               │
│   - SQLite bindings                 │
│   - Object Storage bindings         │
└─────────────────────────────────────┘

Why Component Model?

• Portability: Components run on any Component Model runtime
• Composability: Components can import/export interfaces
• Future-proof: Standard evolving with WebAssembly
• Performance: Near-native execution speed
• Security: Capability-based security model

License

MIT