node-seal ·

node-seal is an ESM-first, WebAssembly-powered wrapper around the C++ Microsoft SEAL homomorphic encryption library, for TypeScript and JavaScript.
v7.0.0 is a breaking release. The custom JS wrapper layer was removed — the package now exposes the Emscripten-generated bindings directly. That makes the package ~96% smaller and faster, but it also means some imports and helper methods changed.
- WebAssembly: Fast, direct bindings to Microsoft SEAL
- ESM-first: Modern module layout, no bundling
- Node.js + browser + edge (CF Workers): Load the WASM separately and run wherever WASM is allowed
- Low-level, close to C++: Method names and types now map much more directly to SEAL
Currently aligned with Microsoft SEAL 4.1.2.
Table of Contents
- Installation
- Quick Start
- What Changed in v7
- Environment Notes
- Demo / Sandbox
- Usage / Docs / Examples
- Benchmarking
- Caveats
- Contributing
- License
Installation
Install from npm:
npm install node-seal
# or
yarn add node-seal
# or
pnpm add node-seal
Because v7 is ESM-first and ships the .wasm separately, most modern bundlers
will just work.
Quick Start
In v7, the default import gives you a factory; call it to get the SEAL runtime:
import SEAL from 'node-seal'
const seal = await SEAL()
Variants:
// recommended and default: throws on transparent ciphertexts
import SEAL from 'node-seal/throws'
const seal = await SEAL()
// allow transparent ciphertexts (only if you know you need this)
import SEAL from 'node-seal/allows'
const seal = await SEAL()
What Changed in v7?
See here.
Environment Notes
React Native
React Native still can't run WASM like a browser. Use a small HTML/JS app inside
a WebView, load node-seal there, and talk over postMessage. Because v7 ships
a plain .wasm, bundling that web app is easier.
Demo
Go to the sandbox
This sandbox was built for users to experiment and learn how to use Microsoft SEAL featuring node-seal.
- Encryption Parameters: experiment with many settings to prototype a SEALContext.
- Keys: Create, download, upload Secret/Public Keys - even for Relinearization and Galois Keys.
- Variables: Create, download, upload PlainTexts or CipherTexts
- Functions: Create a list of HE functions to execute!
- Code Generation: After your experimentation is complete, generate working code to use!
Usage
Checkout the basics
Documentation
View the latest docs here
Examples
Check out the Sandbox to run HE functions and even generate working code!
If you'd rather read an example, take a look here.
For more exhaustive examples, view the tests.
Changes
For changes in this library, take a look here.
For changes in Microsoft SEAL, take a look at their list of changes.
Benchmarking
npm run seal:build:bench
npm run benchmark
See also: BENCHMARK.md.
Caveats
- Memory: saving large keys in the browser is expensive; try a different compression mode if you get OOMs.
- Manual cleanup: call
.delete()or.deleteLater()on created objects to free C++ resources.
Contributing
See CONTRIBUTING.md.
License
node-seal is MIT licensed.