[FEATURE]: MiniChain – Account-Based Proof-of-Work Blockchain Core Prototype

[aniket866]

Feature and its Use Cases

1. Project Goal

• Build a minimal, fully functional blockchain in Python

Core Features

2. Account-Based Ledger

• Use accounts model (not UTXO)

• Each account has:

  a. Address (public key)
  
  b. Balance
  
  c. Nonce
  
  d. Transactions:
  
  e. Signed using PyNaCl
  
  f. Verified before execution
  
  g. Prevent negative balances
  
  h. Prevent replay using nonce
  

3. State Transition Logic

• A simple function:

• new_state = apply_tx(state, tx)

Block validation:

• Verify signatures

• Apply transactions sequentially

• Check invariants (balance ≥ 0, correct nonce)

• Deterministic state update

4. Block Structure

• Minimal block fields:

• Previous block hash

• List of transactions

• Nonce

• Difficulty

• Timestamp

• Block hash

5. Proof of Work (Consensus)

6. Mempool

• Store pending valid transactions

• Remove transactions once included in a block

• Reject invalid or duplicate transactions

7. Peer-to-Peer Networking

• Use Py-libp2p

Broadcast:

• Transactions

• New blocks

• Sync chain between peers

• Bonus Feature

8. Smart Contracts (Optional)

• Use Python as contract language

• Execute in a controlled/sandboxed environment

Basic Project Structure (Minimal)

minichain/
│
├── blockchain.py      # Block & chain logic
├── state.py           # Accounts & state transition
├── transaction.py     # Transaction structure & signing
├── consensus.py       # Proof of Work
├── mempool.py         # Pending transactions
├── network.py         # P2P logic
└── main.py            # Node entry point

Additional Context

hi @Zahnentferner can we start with the above propsed structure and prototype?
Please feel free to assign

Code of Conduct

• I have joined the Discord server and will post updates there
• I have searched existing issues to avoid duplicates