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Smart Contract Security Best Practices for Polygon
Polygon · Chapter 11

Smart Contract Security Best Practices for Polygon

Security begins with clear rules about who can do what. Assume a caller can send unexpected values or use a different interface from yours.

The basics

  • Enforce permissions in the contract. Hiding an admin button in the frontend does not protect the admin function.
  • Reentrancy happens when an external call leads back into your contract before the original operation finishes. Update state before external calls and use established protections when handling funds.
  • Use reviewed libraries for common patterns, and test rejected actions. A successful demo or an automated scan is not proof that a contract is secure.

Try it yourself

Imagine adding reset to Counter. Should anyone be able to reset it? Write the rule first, then a test proving that an unauthorized account cannot do so.

Read more in the official documentation

@ Daniel Burlacu