The summary.
AN UPGRADEABLE CONTRACT IS CONTROLLED BY WHOEVER HOLDS THE UPGRADE AUTHORITY
Which removes the immutability that was the point. Establish who that is before using anything.
CODE EXECUTING IS NOT THE SAME AS AN AGREEMENT BEING ENFORCEABLE
And practice has shown communities overriding code when outcomes were unacceptable — social consensus wins when stakes are high enough.
STORAGE IS THE MOST EXPENSIVE OPERATION BY A WIDE MARGIN
And unbounded loops eventually exceed the limit, making a function permanently unusable.
Use audited libraries for standard functionality rather than reimplementing.
AUDITS SAMPLE; THEY DO NOT PROVE
Audited contracts have lost very large sums. Tell auditors what should be impossible, or they can only check known patterns.
Set bug bounties competitive with exploiting the defect, or the incentive is unchanged.
THE INTERFACE IS USUALLY NOT DECENTRALISED, AND WHOEVER CONTROLS IT CONTROLS WHAT USERS SEE
Verify the transaction, not the interface's description of it. Use wallet simulation for anything unfamiliar.
