l2-deployment

L2 Deployment Patterns

L2 Gas Economics

L2 transaction cost = L2 execution gas + L1 data posting cost

Operation	L1 (Ethereum)	L2 (Base/OP/Arb)	Savings
ETH transfer	~$0.50	~$0.0003	99.9%
ERC-20 transfer	~$2.00	~$0.001	99.9%
Uniswap swap	~$8.00	~$0.002-0.003	99.9%
NFT mint	~$5.00	~$0.002	99.9%
Contract deploy	~$50-500	~$0.05-0.50	99%

Post-EIP-4844 (blobs), L1 data costs dropped 10-100x for L2s.

L2-Specific Considerations

PUSH0 Opcode Compatibility

PUSH0 was introduced in the Shanghai upgrade (EVM version). Some L2s may lag behind on EVM version support:

# foundry.toml — set EVM version explicitly for L2
[profile.default]
evm_version = "cancun"     # Base, Optimism, Arbitrum all support cancun

# If targeting an L2 that doesn't support cancun:
# evm_version = "paris"    # No PUSH0

Block Time Differences

Chain	Block Time	Implication
Ethereum	~12s	Standard
Base	2s	Faster confirmations
Optimism	2s	Faster confirmations
Arbitrum	~0.25s	Near-instant

Avoid hardcoding time assumptions based on block numbers.

L2-Specific Addresses

// Optimism / Base predeploys (same addresses on all OP Stack chains)
address constant L2_CROSS_DOMAIN_MESSENGER = 0x4200000000000000000000000000000000000007;
address constant L2_STANDARD_BRIDGE = 0x4200000000000000000000000000000000000010;
address constant L2_TO_L1_MESSAGE_PASSER = 0x4200000000000000000000000000000000000016;
address constant WETH = 0x4200000000000000000000000000000000000006;
address constant L1_BLOCK = 0x4200000000000000000000000000000000000015;
address constant GAS_PRICE_ORACLE = 0x420000000000000000000000000000000000000F;

// Arbitrum system addresses
address constant ARB_SYS = 0x0000000000000000000000000000000000000064;
address constant ARB_RETRYABLE_TX = 0x000000000000000000000000000000000000006E;