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⚡️ react-native-quick-crypto

A fast implementation of Node's crypto module.

Unlike any other current JS-based polyfills, react-native-quick-crypto is written in C/C++ JSI and provides much greater performance - especially on mobile devices. QuickCrypto can be used as a drop-in replacement for your Web3/Crypto apps to speed up common cryptography functions.

  • 🏎️ Up to 58x faster than all other solutions
  • ⚡️ Lightning fast implementation with pure C++ and JSI, instead of JS
  • 🧪 Well tested in JS and C++ (OpenSSL)
  • 💰 Made for crypto apps and Wallets
  • 🔢 Secure native compiled cryptography
  • 🔁 Easy drop-in replacement for crypto-browserify or react-native-crypto

For example, creating a Wallet using ethers.js uses complex algorithms to generate a private-key/mnemonic-phrase pair:

const start =;
const wallet = ethers.Wallet.createRandom();
const end =;
console.log(`Creating a Wallet took ${end - start} ms.`);

Without react-native-quick-crypto 🐢:

Creating a Wallet took 16862 ms

With react-native-quick-crypto ⚡️:

Creating a Wallet took 289 ms


React Native  

yarn add react-native-quick-crypto
cd ios && pod install


expo install react-native-quick-crypto
expo prebuild

Optional: override global.Buffer and global.crypto in your application as early as possible for example in index.js.

import { install } from 'react-native-quick-crypto';


Replace crypto-browserify

If you are using a library that depends on crypto, instead of polyfilling it with crypto-browserify (or react-native-crypto) you can use react-native-quick-crypto for a fully native implementation. This way you can get much faster crypto operations with just a single-line change!

Using metro config

Use the resolveRequest configuration option in your metro.config.js

config.resolver.resolveRequest = (context, moduleName, platform) => {
  if (moduleName === 'crypto') {
    // when importing crypto, resolve to react-native-quick-crypto
    return context.resolveRequest(
  // otherwise chain to the standard Metro resolver.
  return context.resolveRequest(context, moduleName, platform)

Using babel-plugin-module-resolver

You need to install babel-plugin-module-resolver, it's a babel plugin that will alias any imports in the code with the values you pass to it. It tricks any module that will try to import certain dependencies with the native versions we require for React Native.

yarn add --dev babel-plugin-module-resolver

Then, in your babel.config.js, add the plugin to swap the crypto, stream and buffer dependencies:

module.exports = {
  presets: ['module:metro-react-native-babel-preset'],
  plugins: [
+   [
+     'module-resolver',
+     {
+       alias: {
+         'crypto': 'react-native-quick-crypto',
+         'stream': 'readable-stream',
+         'buffer': '@craftzdog/react-native-buffer',
+       },
+     },
+   ],

Then restart your bundler using yarn start --reset-cache.


For example, to hash a string with SHA256 you can do the following:

import QuickCrypto from 'react-native-quick-crypto';

const hashed = QuickCrypto.createHash('sha256')
  .update('Damn, Margelo writes hella good software!')

Android build errors

If you get an error similar to this:

Execution failed for task ':app:mergeDebugNativeLibs'.
> A failure occurred while executing$MergeNativeLibsTaskWorkAction
   > 2 files found with path 'lib/arm64-v8a/' from inputs:
      - /Users/osp/Developer/mac_test/node_modules/react-native-quick-crypto/android/build/intermediates/library_jni/debug/jni/arm64-v8a/
      - /Users/osp/.gradle/caches/transforms-3/e13f88164840fe641a466d05cd8edac7/transformed/jetified-flipper-0.182.0/jni/arm64-v8a/

It means you have a transitive dependency where two libraries depend on OpenSSL and are generating a file. You can get around this issue by adding the following in your app/build.gradle:

React Native  

android/app/build.gradle file

packagingOptions {
  // Should prevent clashes with other libraries that use OpenSSL
  pickFirst '**/'


app.json file

  plugins: [
+   [
+     'expo-build-properties',
+     {
+       android: {
+         packagingOptions: {
+           pickFirst: ['**/'],
+         },
+       },
+     },
+   ],

This caused by flipper which also depends on OpenSSL

This just tells Gradle to grab whatever OpenSSL version it finds first and link against that, but as you can imagine this is not correct if the packages depend on different OpenSSL versions (quick-crypto depends on You should make sure all the OpenSSL versions match and you have no conflicts or errors.


Onin - This library is supported by Onin. Plan events without leaving the chat:

Omni - Web3 for all. Access all of Web3 in one easy to use wallet. Omni supports more blockchains so you get more tokens, more yields, more NFTs, and more fun!

Litentry - A decentralized identity aggregator, providing the structure and tools to empower you and your identity.

WalletConnect - The communications protocol for web3, WalletConnect brings the ecosystem together by enabling wallets and apps to securely connect and interact.

THORSwap - THORSwap is a cross-chain DEX aggregator that enables users to swap native assets across chains, provide liquidity to earn yield, and more. THORSwap is fully permissionless and non-custodial. No account signup, your wallet, your keys, your coins.


As the library uses JSI for synchronous native methods access, remote debugging (e.g. with Chrome) is no longer possible. Instead, you should use Flipper.

Community Discord

Join the Margelo Community Discord to chat about react-native-quick-crypto or other Margelo libraries.

Adopting at scale

react-native-quick-crypto was built at Margelo, an elite app development agency. For enterprise support or other business inquiries, contact us at!


See the contributing guide to learn how to contribute to the repository and the development workflow.


  • react-native-quick-crypto is licensed under MIT.
  • react-native-quick-crypto is heavily inspired by NodeJS Crypto, which is licensed under nodejs/LICENSE.