10 EVM Gas Optimization Patterns in Solidity 0.8.20+

High execution costs on Ethereum and L2 rollups degrade protocol competitiveness. By profiling EVM opcodes and AST representations, smart contract engineers can eliminate unnecessary gas overhead before deployment.

1. Custom Errors vs Require Strings (~24,000 Gas Saved)

Using error Unauthorized(); revert Unauthorized(); instead of verbose require strings saves bytecode deployment size and runtime revert gas costs by replacing string storage with a 4-byte error selector.

2. Storage Slot Packing (32-Byte Alignment)

Every EVM storage slot is 32 bytes (256 bits). Packing multiple smaller types (e.g. uint128, uint64, address) into the same 32-byte slot eliminates expensive SSTORE opcodes (20,000 gas each).

3. Unchecked Math in Loop Counters

In Solidity 0.8+, integer overflow checks are automatic. Wrapping loop index increments in unchecked { ++i; } eliminates redundant overflow checks and saves ~30-40 gas per iteration.