Blockchain

This is the development of a Proof-of-Work (PoW) blockchain.

Improvements

• Use a cryptographic library: Instead of importing and using the sha256 function directly, it's better to rely on a well-tested cryptographic library for hashing operations like crypto-js or js-sha256 to handle the hashing of blocks.

• Improve the data structure: Currently, the blockchain consists of an array of blocks. While this is functional, using a linked list data structure can provide better performance for blockchain operations. Each block can have a reference to the previous block, forming a chain.

• Validate transactions: Add a validation mechanism for transactions to ensure that they meet certain criteria before being included in a block. For example, check if the sender has sufficient funds and if the transaction signature is valid.

• Include a reward mechanism: In many blockchain implementations, there is a reward given to the miner who successfully mines a block. Consider adding a reward transaction to incentivize miners to continue mining.

• Implement transaction verification: Add a mechanism to verify the integrity and authenticity of transactions, such as using digital signatures or public-key cryptography.

• Implement consensus mechanism: To ensure agreement on the blockchain state among participants, consider implementing a consensus mechanism such as Proof-of-Work (PoW), Proof-of-Stake (PoS), or Practical Byzantine Fault Tolerance (PBFT).

• Implement persistence: The current implementation doesn't include persistence, meaning that the blockchain will be lost when the program terminates. Consider adding functionality to persist the blockchain to disk or a database.

• Handle edge cases: The code doesn't handle scenarios like a chain reorganization or resolving conflicts between different chains. Research techniques like chain selection, fork resolution, and handling double spending attacks to handle these scenarios.