lytol / kapo

Adventures in blockchains and distributed ledgers

Kapo

Just messing around with blockchains and distributed ledgers using Go

Usage

• add : add a transaction to the blockchain (requires private key, account, script, optional data)

Goals

• Small and minimal, do less
• Single binary with no runtime dependencies
• Smart contracts
• Storage oriented (documents, etc)

Architecture

• BoltDB for the ledger database (transactions, blocks)

Resources

• Bitcoin: A Peer-to-Peer Electronic Cash System
• Ethereum White Paper
• Ethereum Source Code
• Storj: A Peer-to-Peer Cloud Storage Network
• IPFS
• Ivan Kuznetsov - Building Blockchain in Go
• Kademlia: A Peer-to-peer Information System Based on the XOR Metric

TODO

• Addresses
• Refactor crypto into its own package
• Refactor mining into "seal" per Ethereum
• Scripting
• Networking
• Permissioned blockchain (read all / permissioned write)
• Proof of work is probably not the right consensus mechanism. Research proof of stake and other consensus algo's that incentivize storing and verifying transactions and documents.
• Merkle tree

Notes

Transactions:

Creation:

- Signature = SIGN(Hash(Address + Script + Data)) + PubKey
- Hash = Hash(Address + Script + Data + Signature)

Verification: - Ensure Hash - Ensure signature from public key - Ensure account from public key

Blocks:

Creation - Hash = Hash(Tx1.Hash + Tx2.Hash + ... + TxN.Hash) - Consensus: PoW, etc

Verification - Ensure Hash - Ensure PoW

Sample Account

DO NOT USE THIS FOR ANYTHING OTHER THAN TESTING

Address: d2e65ab43e6fb51852d261f90ae3c62455461e9055b4a1c6bea965190c4770ec PrivateKey: ed0f33026b50ab641ade1ac428bfded42b9047c54d5d420d1efc50d7793175f4 PublicKey: 118f3ddbe11e271af3ce5e9fdfb1c664f5db82752c44c1571aab8036626d57e99b6018f167a77ac9717b7b5b13d7645932bcd75e75e33f70d15b87912c81528d