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QuickJS Version 3.0 — Breaking Changes Ahead! ​

We're excited to announce Version 3.0 of @sebastianwessel/quickjs! This release introduces a breaking change in how the WASM module is loaded, improving security and providing a clearer separation between the runtime and its dependencies.

If you're upgrading from a previous version, please read this post carefully to avoid runtime errors.

WASM Module Must Now Be Explicitly Imported ​

To comply with stricter security restrictions in Node.js and to allow better customization, the loadAsyncQuickJs and loadQuickJs functions no longer provide default module fallbacks.

New Required Usage (Async): ​

ts
import variant from "@jitl/quickjs-wasmfile-release-asyncify";
const { runSandboxed } = await loadAsyncQuickJs(variant);

New Required Usage (Sync): ​

ts
import variant from "@jitl/quickjs-ng-wasmfile-release-sync";
const { runSandboxed } = loadQuickJs(variant);

Old Usage (No Longer Supported): ​

ts
// ❌ These will now throw an error
const { runSandboxed } = await loadAsyncQuickJs();
const { runSandboxed } = loadQuickJs();

This change ensures that the host application explicitly declares which WASM variant it intends to use, improving clarity and maintainability — especially in advanced environments like bundlers or serverless runtimes.

🔧 Please update your code accordingly and consult the README on GitHub for more examples and updated documentation.

👉 Explore the QuickJS repository

Happy sandboxing! 🧪