coincoin is a cryptocurrency proof-of-concept implemented in Elixir. It's an umbrella project that focuses on the 2 main components of (most of) the existing cryptocurrencies: the blockchain and digital transactions.
It's goal is to be as simple as possible but complete enough to technically understand what's going on behind Bitcoin or Ethereum for example.
Blockchains are P2P softwares. To start using
coincoin, we need to setup multiple nodes and connect them together.
You need Elixir installed. Clone this repository and go to the root of the project.
Then pull the dependencies using
To setup a 3 nodes blockchain, spawn 3 tabs in your terminal (node1, node2 and node3) and run:
iex -S mix phx.server(defaults:
PORT=4001 P2P_PORT=5001 iex -S mix phx.server
PORT=4002 P2P_PORT=5002 iex -S mix phx.server
Then connect the nodes to create a P2P network:
$node2> Blockchain.connect("localhost:5000") # connect node2 to node1 $node3> Blockchain.connect("localhost:5001") # connect node3 to node2
This will setup a simple network:
node1 <--> node2 <--> node3
You can also use the
robinmonjo/coincoin docker image available on the docker hub:
docker run -it robinmonjo/coincoin
If you use Docker, in the
Blockchain.connect/1 call make sure to pass your container IP address and that this address is reachable.
- if you don't want to interact with the REST API, you can skip the
PORTenv var and use
iex -S mixinstead of
iex -S mix phx.server
Blockchain.connect(5000)is equivalent to
- for releases use
coincoin will start 3 apps:
blockchain: a minimal blockchain
token: a minimal cryptocurrency implemented on top of the blockchain
blockchain_web: a web interface to manage nodes of the blockchain
To manipulate the blockchain and store random data in it using the
iex console checkout the
blockchain app. To do the same using a REST API, checkout the
blockchain_web app. And finally to play with a cryptocurrency and use the blockchain as a distributed ledger, checkout the
Why coincoin ?
Lately I heard a lot about:
- how Elixir is awesome and is the future of complex system / web development
- how blockchain technology will be the next big thing
So what about building a cryptocurrency proof-of-concept in Elixir ?
As I'm sure about 1, I still have some doubts about 2 eventough technologies behind cryptocurrencies are exciting.
Also "coin-coin" in french is the noise of a duck (hence Scrooge McDuck)
Issues, suggestions and pull requests are very welcome