This project is based on Jeiwan/blockchain_go and his related blog post.

This project is only a simplified bitcoin implementation not intended to be compatible with current bitcoin protocols.

Designs

Roles

There are no roles such as miner, full nodes and SPVs. Each node will store the whole chain, do PoWs and validate blocks. There is a seperate Cli tool to act like a wallet to send/receive coins.

Tech Stack

• Serialization: protobuf, this is used both for network traffic and data persistence
• Network communication: grpc
• Key-Value Database: bbolt
• Cli framework: cobra

Implemetation details

• node discovery: one node must manually specify a node to connect, then it can use RPC to get other nodes' info
  • since our nodes' number is relatively small, all nodes are connected directly to each other
  • a node periodically announces its connected nodes to all its neighbours

References

• Bitcoin whitepaper
• Bitcoin Protocol Documentation

Things which are not implemented

• Merkle Tree
• Scripts

Issues

• TODO: when verifying a block, need to check if an output is spent twice
• when to update uxto set?
• we can't use an UTXO twice in one block