bc-crypto-ts provides the hashing, symmetric encryption, key derivation, and signature primitives shared across the Blockchain Commons' TypeScript stack.
@blockchaincommons/crypto is published to npm. Install it with your package manager of choice:
npm install @blockchaincommons/crypto
# or
pnpm add @blockchaincommons/crypto
# or
yarn add @blockchaincommons/crypto
# or
bun add @blockchaincommons/cryptoimport {
sha256,
hkdfSha256,
chacha20Poly1305,
ecdsa,
CryptoError,
} from "@blockchaincommons/crypto";
import { randomBytes } from "@blockchaincommons/rand";
// Hashes and KDFs are plain functions.
const digest = sha256(new TextEncoder().encode("hello"));
const key = hkdfSha256(randomBytes(32), new Uint8Array(16), { dkLen: 32 });
// Algorithm families are objects; every function that draws randomness
// takes `{ rng }` and defaults to the secure generator.
const priv = ecdsa.generatePrivateKey();
const sig = ecdsa.sign(priv, digest);
ecdsa.verify(ecdsa.publicKey(priv), sig, digest); // true
// AEAD returns `ciphertext || tag` as one buffer.
// Use a fresh nonce for every encryption under the same key.
const nonce = randomBytes(chacha20Poly1305.NONCE_SIZE);
const sealed = chacha20Poly1305.encrypt(key, nonce, digest, { aad: new Uint8Array(0) });
try {
chacha20Poly1305.decrypt(key, nonce, sealed);
} catch (e) {
if (CryptoError.isCryptoError(e) && e.is("AuthenticationFailed")) {
/* tampered */
}
}Every byte argument must be a Uint8Array (a Buffer qualifies); a string, array or ArrayBuffer is CryptoError InvalidParameter, named after the argument, before any other check. As in the reference, a low-order X25519 peer derives one fixed key (HKDF of the all-zero secret): reject such peers yourself before deriving from an untrusted key.
memzero(bytes) and memzeroAll(arrays) overwrite a typed array with zeros as a best effort. JavaScript has no volatile writes and an engine may keep copies of a buffer, so treat them as defence in depth, not as a guarantee that a key has left memory.
Runnable examples live in the examples/ directory.
bc-crypto-ts is currently under active development and in beta testing. It should not be used for production tasks until it has had further testing and auditing. See Blockchain Commons' Development Phases.
- 1.0.0-beta.3 (September 14, 2026) - Every argument is type-checked before anything else (a non-
Uint8Arraybyte argument isInvalidParameter); a low-order X25519 peer derives the reference's key;verifythrowsInvalidData; PBKDF2iterations: 0and scryptlogN: 0derive; hybrid06/07uncompressed keys compress; PBKDF2 acceptsdkLenup to (2^32 − 1)·hLen. - 1.0.0-beta.2 (September 12, 2026) - Ed25519 uses the Rust reference's uncofactored verification equation; ChaCha20 counter-overflow reports
InvalidParameter; scrypt validates its backend limits. scrypt mirrors the reference's parameter rules (logN < 16·r,r·p < 2^30, the parameterised path's10..=64output length) and gainsmaxmem; PBKDF2 acceptsdkLen: 0with positive iterations; argon2id keeps only the reference's fixed costs. - 1.0.0-beta.1 (September 9, 2026) - Initial beta implementation.
- Continued testing and auditing on the path from beta to a stable 1.0.0 release.
- Continued parity with the Rust reference implementation as it evolves (see
RUST_DIVERGENCES.md).
@blockchaincommons/crypto depends on @blockchaincommons/rand, @noble/ciphers, @noble/curves, @noble/hashes at runtime.
To build and work on this library, you'll need the following tools:
- Node.js >= 22.12 - JavaScript runtime.
- Bun - used to install dependencies and run scripts (any node package manager works).
- TypeScript >= 5.7 - language and type checker.
This bc-crypto-ts project is either derived from or was inspired by:
- BlockchainCommons/bc-crypto-rust - The reference Rust implementation, by Wolf McNally.
- paritytech/bcts - A TypeScript port of many Blockchain Commons' specs, by Parity Technologies.
bc-crypto-ts is a project of Blockchain Commons. We are proudly a "not-for-profit" social benefit corporation committed to open source & open development. Our work is funded entirely by donations and collaborative partnerships with people like you. Every contribution will be spent on building open tools, technologies, and techniques that sustain and advance blockchain and internet security infrastructure and promote an open web.
To financially support further development of bc-crypto-ts and other projects, please consider becoming a Patron of Blockchain Commons through ongoing monthly patronage as a GitHub Sponsor. You can also support Blockchain Commons with bitcoins at our BTCPay Server.
We encourage public contributions through issues and pull requests! Please review CONTRIBUTING.md for details on our development process. All contributions to this repository require a GPG signed Contributor License Agreement.
The best place to talk about Blockchain Commons and its projects is in our GitHub Discussions areas.
Gordian Developer Community. For standards and open-source developers who want to talk about interoperable wallet specifications, please use the Discussions area of the Gordian Developer Community repo. This is where you talk about Gordian specifications such as Gordian Envelope, bc-shamir, Sharded Secret Key Reconstruction, and bc-ur as well as the larger Gordian Architecture, its Principles of independence, privacy, resilience, and openness, and its macro-architectural ideas such as functional partition (including airgapping, the original name of this community).
Gordian User Community. For users of the Gordian reference apps, including Gordian Coordinator, Gordian Seed Tool, Gordian Server, Gordian Wallet, and SpotBit as well as our whole series of CLI apps. This is a place to talk about bug reports and feature requests as well as to explore how our reference apps embody the Gordian Principles.
Blockchain Commons Discussions. For developers, interns, and patrons of Blockchain Commons, please use the discussions area of the Community repo to talk about general Blockchain Commons issues, the intern program, or topics other than those covered by the Gordian Developer Community or the Gordian User Community.
As an open-source, open-development community, Blockchain Commons does not have the resources to provide direct support of our projects. Please consider the discussions area as a locale where you might get answers to questions. Alternatively, please use this repository's issues feature. Unfortunately, we can not make any promises on response time.
If your company requires support to use our projects, please feel free to contact us directly about options. We may be able to offer you a contract for support from one of our contributors, or we might be able to point you to another entity who can offer the contractual support that you need.
The following people directly contributed to this repository. You can add your name here by getting involved. The first step is learning how to contribute from our CONTRIBUTING.md documentation.
| Name | Role | Github | GPG Fingerprint | |
|---|---|---|---|---|
| Christopher Allen | Principal Architect | @ChristopherA | <ChristopherA@LifeWithAlacrity.com> | FDFE 14A5 4ECB 30FC 5D22 74EF F8D3 6C91 3574 05ED |
| Wolf McNally | Lead Researcher/Engineer | @wolfmcnally | <Wolf@WolfMcNally.com> | 9436 52EE 3844 1760 C3DC 3536 4B6C 2FCF 8947 80AE |
| Leonardo Custodio | Software Engineer | @leonardocustodio | <leonardo@snowpine.io> | 59DA D997 67EF 3BAB 2B90 D057 5384 DEF3 B582 450D |
Blockchain Commons Cryptographic Utilities for TypeScript was produced as a collaboration between Blockchain Commons and one of our patrons, Parity Technologies: Parity wrote the wrappers based on Blockchain Commons' specifications and reference libraries. Blockchain Commons is dedicated to not just creating open infrastructure on our own, but also coordinating the work of other companies in benefiting the Commons. Thanks to Parity for working directly with us in this manner.
We want to keep all of our software safe for everyone. If you have discovered a security vulnerability, we appreciate your help in disclosing it to us in a responsible manner. We are unfortunately not able to offer bug bounties at this time.
We do ask that you offer us good faith and use best efforts not to leak information or harm any user, their data, or our developer community. Please give us a reasonable amount of time to fix the issue before you publish it. Do not defraud our users or us in the process of discovery. We promise not to bring legal action against researchers who point out a problem provided they do their best to follow the these guidelines.
Please report suspected security vulnerabilities in private via email to ChristopherA@BlockchainCommons.com (do not use this email for support). Please do NOT create publicly viewable issues for suspected security vulnerabilities.
The following keys may be used to communicate sensitive information to developers:
| Name | Fingerprint |
|---|---|
| Christopher Allen | FDFE 14A5 4ECB 30FC 5D22 74EF F8D3 6C91 3574 05ED |
You can import a key by running the following command with that individual’s fingerprint: gpg --recv-keys "<fingerprint>" Ensure that you put quotes around fingerprints that contain spaces.