CSecp256k1 0.2.0

CSecp256k1 0.2.0

Maintained by Yehor Popovych.

  • By
  • Tesseract Systems, Inc.


🐧 linux: ready GitHub license Build Status GitHub release SPM compatible CocoaPods version Platform macOS | iOS | tvOS | watchOS | Linux

Swift C module for bitcoin secp256k1 library.


CSecp256k1.swift deploys to macOS, iOS, tvOS, watchOS and Linux. It has been tested on the latest OS releases only however, as the module uses very few platform-provided APIs, there should be very few issues with earlier versions.

Setup instructions:

  • Swift Package Manager: Add this to the dependency section of your Package.swift manifest:

    .package(url: "https://github.com/tesseract-one/CSecp256k1.swift.git", from: "0.2.0")
  • CocoaPods: Put this in your Podfile:

    pod 'CSecp256k1', '~> 0.2'

Usage Examples

Sign and Verify

import CSecp256k1

let privKey: [UInt8] = [
    0x9d, 0x61, 0xb1, 0x9d, 0xef, 0xfd, 0x5a, 0x60, 0xba,
    0x84, 0x4a, 0xf4, 0x92, 0xec, 0x2c, 0xc4, 0x44, 0x49,
    0xc5, 0x69, 0x7b, 0x32, 0x69, 0x19, 0x70, 0x3b, 0xac,
    0x03, 0x1c, 0xae, 0x7f, 0x60

let data = [UInt8](repeating: 0, count: 32)

let context: OpaquePointer! = secp256k1_context_create(

var signature = secp256k1_ecdsa_recoverable_signature()
let res = secp256k1_ecdsa_sign_recoverable(context, &signature, data, privKey, nil, nil)
assert(res > 0)

var pubKey = secp256k1_pubkey()
let res2 = secp256k1_ec_pubkey_create(context, &pubKey, privKey)
assert(res2 > 0)

var ssig = secp256k1_ecdsa_signature()
let res3 = secp256k1_ecdsa_recoverable_signature_convert(context, &ssig, &signature)
assert(res3 > 0)

let isValid = secp256k1_ecdsa_verify(context, &ssig, hash, &pubKey)
assert(isValid == 1)


CSecp256k1.swift can be used, distributed and modified under the Apache 2.0 license.

Bitcoin secp256k1 can be used, distributed and modified under the MIT license.