Blockchain Basics

Blockchain challenges focus on smart contracts and on-chain applications: how storage, calls and assets behave.

In progress

This category is being written. Planned topics:

• Blockchain fundamentals and the EVM execution model
• Solidity and contract deployment
• Reentrancy
• Integer issues, access control and permission bypass
• Randomness and timestamp manipulation
• Proxy contracts and upgrade bugs
• Flash loans, oracles and price manipulation
• Foundry and Slither for auditing and debugging

Study tips

1. Understand accounts, transactions, gas and contract storage.
2. Use Foundry to reproduce and debug calls locally.
3. Start with simple contract audits, then study real incidents.