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= tBTC

IMPORTANT: This repository has been archived. tBTC v1 is no longer actively maintained and has been superseded by tBTC v2. tBTC v2 code is available in the link:https://github.com/keep-network/tbtc-v2[keep-network/tbtc-v2] repository.

tBTC is a trustlessly Bitcoin-backed ERC-20 token.

The goal of the project is to provide a stronger 2-way peg than federated sidechains like https://blockstream.com/liquid/[Liquid], expanding use cases possible via today's Bitcoin network, while bringing superior money to other chains.

This repo contains the Solidity link:solidity/[smart contracts] and link:docs/[specification].

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== Getting started

• Read the link:./docs/introduction-to-tbtc.md[introduction to tBTC].
• Read the http://docs.keep.network/tbtc/[specification].
• Consult http://docs.keep.network/tbtc/solidity/[Solidity API documentation].
• For questions and support, join the #tbtc-protocol channel on https://discord.gg/4R6RGFf[Discord].

== Installation

tBTC contracts are currently published in the NPM Registry as the package https://www.npmjs.com/package/@keep-network/tbtc[`@keep-network/tbtc`]. Packages have versions corresponding to their network:

• -dev packages contain prerelease packages for the internal Keep testnet.
• -ropsten packages contain prerelease packages for the Ropsten Ethereum testnet.

Note that only the latest package in a series is expected to reference contracts that have a backing set of signers.

To install the package:

$ npm install @keep-network/tbtc

NOTE: The tbtc package contains an indirect dependency to @summa-tx/relay-sol@2.0.2 package, which downloads one of its sub-dependencies via unathenticated git:// protocol. That protocol is no longer supported by GitHub. This means that in certain situations installation of the package may result in The unauthenticated git protocol on port 9418 is no longer supported error. + As a workaround, we advise changing Git configuration to use https:// protocol instead of git:// by executing:

git config --global url."https://".insteadOf git://

== Usage

NOTE: tBTC contracts require solc v0.5.17 or higher. You may have to https://www.trufflesuite.com/docs/truffle/reference/configuration#compiler-configuration[configure solc in your truffle-config.js].

Once installed, you can use the contracts in the library by importing them:

[source,sol]

pragma solidity ^0.5.17;

import "@keep-network/tbtc/contracts/deposit/Deposit.sol";

contract MySystem { function checkTerm(address _depositAddress) external { uint256 remainingTerm = Deposit(_depositAddress).remainingTerm(); } }

== Security

tBTC's first 6-week audit was completed by ConsenSys Diligence on March 27, 2020, against https://github.com/keep-network/tbtc/commit/fbb2018c41456d19ec20eb28a17070ee2b10eb5d[fbb2018c41]. They've published a detailed https://diligence.consensys.net/audits/2020/02/thesis-tbtc-and-keep/[audit report] and https://diligence.consensys.net/audits/2020/03/thesis-cryptographic-review/[cryptographic review].

A Bitcoin-focused audit was conducted by security researcher https://twitter.com/sr_gi[Sergi Delgado] from May 25 to May 31, 2020. You can https://srgi.me/resources/reports/tbtc_audit.pdf[review Sergi's results on his site].

https://www.trailofbits.com/[Trail of Bits] conducted an audit of tBTC in June, 2020, and published a https://github.com/trailofbits/publications/blob/db9414def9f575465a47fef5489eb54d9c543eb5/reviews/thesis-summary.pdf[a summary of their results]. https://github.com/samczsun[`@samczsun`] opened issues he discovered https://github.com/keep-network/tbtc/issues?q=is%3Aissue+author%3Asamczsun[on the repo], all of which have been addressed.

A focused treatment of tBTC's security model can be https://tbtc.network/developers/tbtc-security-model/[found here].

Please dislose any security issues you find or suspect to mailto:security@keep.network[security@keep.network], or to https://keybase.io/shadowfiend[`@shadowfiend], https://keybase.io/frdwrd[@frdwrd], or https://keybase.io/mhluongo[@mhluongo`] via Keybase.

== Contributing

All contributions are welcome. To report bugs, please create an issue on this repository. To start a discussion, prefer https://discord.gg/4R6RGFf[Discord] over GitHub issues.

Read the xref:CONTRIBUTING.adoc[Contributing guidelines].

=== Setup environment

You should have installed:

• Node.js, https://docs.npmjs.com/cli/install[npm].
• A local Ethereum blockchain. We recommend https://www.trufflesuite.com/ganache[Ganache].
• https://www.trufflesuite.com/docs/truffle/overview[Truffle framework].

=== Build

Clone and install dependencies:

[source,sh]

git clone https://github.com/keep-network/tbtc cd tbtc/solidity npm install

Deploy contracts:

[source,sh]

truffle migrate --reset

=== Test

Tests are written in JS using Mocha.

To run the test suite, execute truffle test.

To run specific tests, add https://jaketrent.com/post/run-single-mocha-test/[`.only] to the contract` block:

[source,js]

contract.only('TBTCToken', function(accounts) {

=== Lint

We use https://eslint.org/[ESLint] and https://github.com/duaraghav8/Ethlint[Ethlint] for linting code. To run:

[source,sh]

npm run sol:lint:fix npm run js:lint:fix

== Documentation

The documentation includes a project overview and rationale, as well as the on-chain specification. Docs should always be updated before or in tandem with code.

=== Prerequisites

Docs are written in http://asciidoctor.org/[AsciiDoctor], with diagrams in https://asciidoctor.org/docs/asciidoctor-diagram/#mermaid[Mermaid].

==== macOS

Install the dependencies via CLI: + [source,sh]

gem install asciidoctor-pdf --pre brew install poppler

=== Build

[source,sh]

cd docs

Generate index.pdf

asciidoctor-pdf index.adoc

== License

tBTC is released under the link:LICENSE[MIT License].