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Chain Line

Get anything anywhere, powered by the blockchain. Chain Line is a peer-to-peer shipping network that gets products and valuable items to their destinations with near-zero risk.

It works by moving an item's cost between peers as it travels through the system. A central "hub" contract controls "reserved funds" in Chain Line smart wallets running custom verification scripts. Chain Line features a user reputation system and relies on no external systems, operating entirely on the blockchain.

Learn more:   Wiki   User Guide   Intro Video

Chain Line Contracts

The smart contracts powering Chain Line run on the NEO blockchain and were written in Kotlin.

Project structure

  • ./ The Kotlin project containing contract sources
  • ./unit-tests The .NET Core project containing VM based contract tests
  • ./vendor/* External dependencies

Building the contracts

  • Install the .NET Core v1.1 SDK
  • Install JDK 8 and Maven
  • Clone this repository and run make

Compiled contract avm files may be found in the root directory of the project.

Note: You might have to put org.neo.smartcontract.framework.jar somewhere dotnet can find it (try your PATH or /usr/local/share/dotnet). You can build the jar by running mvn install in vendor/neo-devpack-java. It will be created in target.

Running the tests

Run make test (the easy way) or

  • Install Visual Studio
  • Open the unit tests project in ./unit-tests/CLTests.sln
  • Run the tests within the IDE (on a Mac this is done through View > Pads > Unit Tests then click Run All in the side pane)

Generating the docs

Dokka is used to generate the docs as an HTML site. Run make docs to generate the pages and then look in target/dokka/chainline-contracts.

A snapshot of the docs is accessible via GitHub Pages.