Part 4: Optimasi & Deployment SimpleBank

🎯 Tujuan Module

Setelah menyelesaikan module ini, Anda akan mampu:

✅ Memahami dan menerapkan gas optimization techniques
✅ Mengukur gas usage dengan gas snapshots
✅ Mengimplementasikan gas-saving patterns pada SimpleBank
✅ Men-deploy SimpleBank ke Lisk Sepolia testnet
✅ Memverifikasi contract di Blockscout
✅ Menggunakan production deployment checklist

💡 Why Gas Optimization Matters?

Analogi: Gas = Biaya Bensin

Berkendara dari Jakarta ke Bandung:

Mobil boros (20L/100km):
- Bensin: 30 liter x Rp 15,000 = Rp 450,000
- Biaya tinggi! 💸

Mobil irit (8L/100km):
- Bensin: 12 liter x Rp 15,000 = Rp 180,000
- Hemat Rp 270,000! ✅

Lesson: Efficiency = uang hemat

Smart Contract di Ethereum:

Contract boros (200,000 gas):
- Gas: 200,000 x 50 gwei = 0.01 ETH
- Dengan ETH @ $3000: $30 per transaksi
- 100 users = $3,000 total cost! 💸

Contract irit (50,000 gas):
- Gas: 50,000 x 50 gwei = 0.0025 ETH
- Dengan ETH @ $3000: $7.50 per transaksi
- 100 users = $750 total cost
- Hemat $2,250! ✅

Lesson: Optimization = happy users

Real Examples:

Uniswap V3:

Setiap 1% gas reduction = millions of dollars saved for users
Optimization adalah top priority

OpenSea:

Gas optimization membuat NFT trading affordable
Tanpa optimization = only whales bisa afford

Takeaway: Optimize = Care about users 💚

📊 Measure Current Gas Usage

Step 1: Run Gas Report

forge test --gas-report

Current SimpleBank gas usage:

| Function             | min   | avg   | median | max   | # calls |
|---------------------|-------|-------|--------|-------|---------|
| deposit              | 45123 | 56234 | 56012  | 67345 | 15      |
| withdraw             | 32456 | 43567 | 43345  | 54678 | 10      |
| transfer             | 28901 | 39012 | 38890  | 49123 | 8       |
| getBalance           | 567   | 567   | 567    | 567   | 5       |
| getTotalDeposits     | 456   | 456   | 456    | 456   | 3       |

Baseline established! Now let's optimize.

Step 2: Create Gas Snapshot

forge snapshot

Creates .gas-snapshot file:

SimpleBankTest:test_Deposit() (gas: 56789)
SimpleBankTest:test_Withdraw() (gas: 89234)
SimpleBankTest:test_Transfer() (gas: 112345)
...

After optimization, compare:

forge snapshot --diff

Shows before/after comparison! 📊

⚡ Gas Optimization Techniques

Technique 1: Use `uint256` Instead of Smaller Types

Why? EVM works in 32-byte words.

❌ Less efficient:

contract Inefficient {
    uint8 public count;      // Padded to 32 bytes anyway
    uint16 public total;     // Padded to 32 bytes
    uint128 public value;    // Padded to 32 bytes

    function increment() public {
        count++;  // Extra operations untuk mask bits
    }
}

✅ More efficient:

contract Efficient {
    uint256 public count;    // Native 32 bytes
    uint256 public total;    // Native 32 bytes
    uint256 public value;    // Native 32 bytes

    function increment() public {
        count++;  // Direct operation, no masking
    }
}

Gas savings: ~200 gas per operation

Exception: Pack multiple small variables into one slot:

contract Packed {
    uint128 public a;  // Slot 0 (first half)
    uint128 public b;  // Slot 0 (second half) ✅ Shared slot!
    uint256 public c;  // Slot 1
}

Technique 2: Caching Storage Variables

Analogy:

Storage = Hard disk (expensive to access)
Memory   = RAM (cheap to access)

Reading storage 3 times:
  disk → disk → disk (3x expensive reads)

Caching in memory:
  disk → RAM → RAM → RAM (1x expensive + 2x cheap)

❌ Inefficient (multiple storage reads):

function expensiveFunction() public {
    require(balances[msg.sender] > 0);
    require(balances[msg.sender] >= 1 ether);
    balances[msg.sender] -= 1 ether;
    // balances[msg.sender] read 3 times = 3 x SLOAD (2100 gas each)
    // Total: ~6300 gas just for reads
}

✅ Efficient (cache in memory):

function cheaperFunction() public {
    uint256 userBalance = balances[msg.sender]; // 1x SLOAD (2100 gas)
    require(userBalance > 0);
    require(userBalance >= 1 ether);
    balances[msg.sender] = userBalance - 1 ether; // 1x SSTORE
    // Total: 2100 gas for read (saves 4200 gas!)
}

Gas savings: ~4200 gas (67% reduction for reads!)

Technique 3: Use Custom Errors Instead of require Strings

❌ Expensive (store error string):

require(amount > 0, "Amount must be greater than zero");
// String stored on-chain = expensive!
// Gas cost: ~2400 gas

✅ Cheap (custom error):

error ZeroAmount();

if (amount == 0) revert ZeroAmount();
// No string storage!
// Gas cost: ~200 gas

Gas savings: ~2200 gas per error (91% cheaper!)

We already did this! ✅ SimpleBank uses custom errors.

Technique 4: Use `calldata` Instead of `memory` for Read-Only Parameters

❌ Expensive:

function processData(string memory data) public {
    // data copied to memory
    // Cost: ~1000 gas for copy
}

✅ Cheap:

function processData(string calldata data) public {
    // data stays in calldata (no copy)
    // Cost: ~50 gas
}

When to use calldata:

External functions only
Parameter is read-only (not modified)
Arrays, strings, structs

Gas savings: ~950 gas per call

Technique 5: Use `++i` Instead of `i++` in Loops

❌ Less efficient:

for (uint256 i = 0; i < 10; i++) {
    // i++ creates temporary variable
    // ~5 extra gas per iteration
}

✅ More efficient:

for (uint256 i = 0; i < 10; ++i) {
    // ++i increments directly
    // No temporary variable
}

Or even better - unchecked:

for (uint256 i = 0; i < 10;) {
    // ... code ...

    unchecked { ++i; }  // No overflow check
    // Solidity ^0.8.0 has auto overflow checks
    // In loops, we know i won't overflow
    // Saves ~30 gas per iteration
}

Gas savings: ~30 gas per iteration

Technique 6: Short-Circuit with `&&` and `||`

❌ All conditions evaluated:

if (expensiveCheck() && cheapCheck()) {
    // Both always execute
}

✅ Short-circuit evaluation:

if (cheapCheck() && expensiveCheck()) {
    // If cheapCheck() false, expensiveCheck() not called!
    // Saves gas when first condition fails
}

Order matters:

// ✅ Good: cheap first
if (amount > 0 && balances[msg.sender] >= amount) {
    // amount > 0 is cheap (memory read)
    // balances[...] is expensive (storage read)
}

// ❌ Bad: expensive first
if (balances[msg.sender] >= amount && amount > 0) {
    // Always reads storage, even if amount = 0
}

Technique 7: Use Events Instead of Storage for Historical Data

❌ Expensive (store on-chain):

struct Transaction {
    address from;
    address to;
    uint256 amount;
    uint256 timestamp;
}

Transaction[] public allTransactions; // Expensive storage!

function transfer(...) public {
    allTransactions.push(Transaction(...)); // ~20,000 gas per push
}

✅ Cheap (use events):

event Transfer(address indexed from, address indexed to, uint256 amount, uint256 timestamp);

function transfer(...) public {
    emit Transfer(msg.sender, to, amount, block.timestamp);
    // Only ~1,500 gas!
}

// Frontend can query events for history
// Events stored in logs (much cheaper)

Gas savings: ~18,500 gas per transaction (93% cheaper!)

We already did this! ✅ SimpleBank emits events.

🔄 Optimize SimpleBank Contract

Let's apply optimizations to SimpleBank:

Create SimpleBankOptimized.sol

// SPDX-License-Identifier: MIT
pragma solidity ^0.8.30;

/**
 * @title SimpleBankOptimized
 * @notice Gas-optimized version of SimpleBank
 */
contract SimpleBankOptimized {
    // ============ Custom Errors (Already optimized!) ============

    error InsufficientBalance(uint256 requested, uint256 available);
    error ZeroAmount();
    error TransferFailed();

    // ============ State Variables ============

    mapping(address => uint256) public balances;

    // ============ Events (Already optimized!) ============

    event Deposited(address indexed user, uint256 amount);
    event Withdrawn(address indexed user, uint256 amount);
    event Transferred(address indexed from, address indexed to, uint256 amount);

    // ============ Functions ============

    function deposit() external payable {
        // Optimization: Use external instead of public
        // External = cheaper for external calls (calldata instead of memory)

        if (msg.value == 0) revert ZeroAmount();

        balances[msg.sender] += msg.value;

        emit Deposited(msg.sender, msg.value);
    }

    function withdraw(uint256 amount) external {
        // Optimization: Cache storage variable
        uint256 userBalance = balances[msg.sender]; // 1x SLOAD

        if (amount == 0) revert ZeroAmount();

        if (userBalance < amount) {
            revert InsufficientBalance(amount, userBalance);
        }

        // CEI Pattern: Update state before transfer
        unchecked {
            // Safe: we checked userBalance >= amount above
            balances[msg.sender] = userBalance - amount;
        }

        // Transfer ETH
        (bool success, ) = msg.sender.call{value: amount}("");
        if (!success) revert TransferFailed();

        emit Withdrawn(msg.sender, amount);
    }

    function transfer(address to, uint256 amount) external {
        // Optimization: Cache storage variable
        uint256 senderBalance = balances[msg.sender]; // 1x SLOAD

        if (amount == 0) revert ZeroAmount();

        if (senderBalance < amount) {
            revert InsufficientBalance(amount, senderBalance);
        }

        // Update balances
        unchecked {
            // Safe: we checked senderBalance >= amount above
            balances[msg.sender] = senderBalance - amount;
        }
        balances[to] += amount; // 1x SLOAD, 1x SSTORE

        emit Transferred(msg.sender, to, amount);
    }

    function getBalance(address account) external view returns (uint256) {
        return balances[account];
    }

    function getTotalDeposits() external view returns (uint256) {
        return address(this).balance;
    }
}

Key optimizations applied:

✅ external instead of public (cheaper for external calls)
✅ Cache storage variables in memory
✅ unchecked for safe arithmetic (no overflow checks)
✅ Custom errors (already had this!)
✅ Events instead of storage (already had this!)

📊 Compare Gas Usage

Run Gas Comparison

# Original contract
forge test --gas-report --match-contract SimpleBankTest

# Optimized contract
forge test --gas-report --match-contract SimpleBankOptimizedTest

Expected savings:

Function	Original	Optimized	Savings
deposit	56,234	50,123	~11%
withdraw	43,567	38,234	~12%
transfer	39,012	34,567	~11%

Total savings: ~10-12% gas reduction! ⚡

Snapshot Comparison

# Create snapshot for original
forge snapshot --snap original.snap

# Make optimizations
# ...

# Create snapshot for optimized
forge snapshot --snap optimized.snap

# Compare
forge snapshot --diff original.snap

Output:

testDeposit() (gas: -3111 ⬇️ 5.5%)
testWithdraw() (gas: -2765 ⬇️ 6.3%)
testTransfer() (gas: -2234 ⬇️ 5.7%)

Green numbers = savings! ✅

🚀 Deployment Scripts

Create Deployment Script

Buat file script/DeploySimpleBank.s.sol:

// SPDX-License-Identifier: MIT
pragma solidity ^0.8.30;

import {Script, console} from "forge-std/Script.sol";
import {SimpleBank} from "../src/SimpleBank.sol";

/**
 * @title DeploySimpleBank
 * @notice Script untuk deploy SimpleBank contract
 */
contract DeploySimpleBank is Script {
    function run() external returns (SimpleBank) {
        // Start broadcasting transactions
        vm.startBroadcast();

        // Deploy contract
        SimpleBank bank = new SimpleBank();

        console.log("SimpleBank deployed to:", address(bank));

        // Stop broadcasting
        vm.stopBroadcast();

        return bank;
    }
}

Script explanation:

contract DeploySimpleBank is Script {

Deploy scripts inherit from Script
Naming: Deploy<ContractName>

vm.startBroadcast();

Start recording transactions untuk broadcast
Transactions akan di-sign dengan private key dari env

SimpleBank bank = new SimpleBank();

Deploy contract
Returns deployed instance

vm.stopBroadcast();

Stop recording transactions

🌐 Deploy to Lisk Sepolia Testnet

📚 Dokumentasi ini mengikuti best practices dari:

Lisk Official Developer Docs
Foundry + Blockscout integration
Production-ready deployment workflow

Step 1: Setup Environment Variables

Buat file .env:

# Private key (NO 0x prefix!)
PRIVATE_KEY=your_private_key_here

# RPC URL
LISK_SEPOLIA_RPC_URL=https://rpc.sepolia-api.lisk.com

# Etherscan API key (gunakan dummy value untuk Blockscout)
ETHERSCAN_API_KEY=123

⚠️ SECURITY:

Never commit .env to git!
Use testnet wallet only!
Gitignore already includes .env

Step 2: Load Environment Variables

source .env

Or use --env-file flag with forge.

Step 3: Deploy to Lisk Sepolia

Ada 2 cara untuk deploy contract ke Lisk Sepolia:

Opsi 1: forge create (Recommended - Simple & Fast)

Sesuai dokumentasi resmi Lisk:

forge create --rpc-url $LISK_SEPOLIA_RPC_URL \
    --etherscan-api-key $ETHERSCAN_API_KEY \
    --verify \
    --verifier blockscout \
    --verifier-url https://sepolia-blockscout.lisk.com/api \
    --private-key $PRIVATE_KEY \
    src/SimpleBank.sol:SimpleBank

Flags explanation:

--rpc-url = Lisk Sepolia RPC endpoint
--etherscan-api-key 123 = Dummy value (Blockscout tidak perlu API key)
--verify = Auto-verify setelah deploy
--verifier blockscout = Use Blockscout verifier
--verifier-url = Blockscout API endpoint
--private-key = Your private key untuk deploy

💡 Best Practice: Gunakan metode ini untuk contract sederhana (no constructor params atau simple params)

Opsi 2: forge script (Advanced - For Complex Deployments)

Untuk deployment dengan logic kompleks:

# Dry run (simulation)
forge script script/DeploySimpleBank.s.sol --rpc-url $LISK_SEPOLIA_RPC_URL

# Deploy for real
forge script script/DeploySimpleBank.s.sol \
    --rpc-url $LISK_SEPOLIA_RPC_URL \
    --broadcast \
    --verify \
    --verifier blockscout \
    --verifier-url https://sepolia-blockscout.lisk.com/api \
    -vvvv

💡 Use Case: Multi-contract deployments, complex initialization, atau deployment dengan conditional logic

Step 4: Expected Output

Output dari `forge create` (Opsi 1):

[⠒] Compiling...
[⠢] Compiling 1 files with Solc 0.8.30
[⠆] Solc 0.8.30 finished in 1.23s
Compiler run successful!

Deployer: 0x5e1A92F84cA1CE280B3Cb29d79C3368f45b41EBB
Deployed to: 0x108872F713A27bc22ca1db8CEefCAC8CbeDdF9E5
Transaction hash: 0xf465528f43e5cbc9b5206e46048feba0b920179813c3eb8c3bdbccbfd13d731e

Starting contract verification...
Waiting for blockscout to detect contract deployment...

Start verifying contract `0x108872F713A27bc22ca1db8CEefCAC8CbeDdF9E5` deployed on 4202

Submitting verification for [src/SimpleBank.sol:SimpleBank] 0x108872F713A27bc22ca1db8CEefCAC8CbeDdF9E5.
Submitted contract for verification:
        Response: `OK`
        GUID: `108872f713a27bc22ca1db8ceefcac8cbeddf9e565e71790`
        URL: https://sepolia-blockscout.lisk.com/address/0x108872f713a27bc22ca1db8ceefcac8cbeddf9e5

Contract verification status:
Response: `OK`
Details: `Pending in queue`

Contract verification status:
Response: `OK`
Details: `Pass - Verified`

Contract successfully verified

🎉 Deployed & Verified on Lisk Sepolia!

📝 Save this information:

Contract Address: 0x108872F713A27bc22ca1db8CEefCAC8CbeDdF9E5
Transaction Hash: 0xf465528f43e5cbc9b5206e46048feba0b920179813c3eb8c3bdbccbfd13d731e
Block Explorer: https://sepolia-blockscout.lisk.com/address/0x108872f713a27bc22ca1db8ceefcac8cbeddf9e5

💰 Gas Savings on Lisk:

Ethereum Sepolia: ~0.01 ETH (20 gwei gas price)
Lisk Sepolia: ~0.0003 ETH (0.5 gwei gas price)
Savings: 97% cheaper! ⚡

🔍 Verify Contract Manually

Jika auto-verify gagal saat deployment, Anda bisa verify contract secara manual.

Sesuai dokumentasi resmi Lisk:

forge verify-contract <CONTRACT_ADDRESS> \
    src/SimpleBank.sol:SimpleBank \
    --chain 4202 \
    --watch \
    --verifier blockscout \
    --verifier-url https://sepolia-blockscout.lisk.com/api

Example:

forge verify-contract 0x108872F713A27bc22ca1db8CEefCAC8CbeDdF9E5 \
    src/SimpleBank.sol:SimpleBank \
    --chain 4202 \
    --watch \
    --verifier blockscout \
    --verifier-url https://sepolia-blockscout.lisk.com/api

Expected Output:

Starting contract verification...
Waiting for blockscout to detect contract deployment...

Start verifying contract `0x108872F713A27bc22ca1db8CEefCAC8CbeDdF9E5` deployed on 4202

Submitting verification for [src/SimpleBank.sol:SimpleBank] 0x108872F713A27bc22ca1db8CEefCAC8CbeDdF9E5.
Submitted contract for verification:
       Response: `OK`
       GUID: `108872f713a27bc22ca1db8ceefcac8cbeddf9e565e71790`
       URL: https://sepolia-blockscout.lisk.com/address/0x108872f713a27bc22ca1db8ceefcac8cbeddf9e5

Contract verification status:
Response: `OK`
Details: `Pending in queue`

Contract verification status:
Response: `OK`
Details: `Pass - Verified`

Contract successfully verified

💡 Important Notes:

No API key needed untuk Blockscout!
--chain 4202 = Chain ID untuk Lisk Sepolia
--watch = Monitor verification status real-time
Gunakan contract address dari deployment output

Check verification di Blockscout:

https://sepolia-blockscout.lisk.com/address/0xYourContractAddress

Should show "Verified" badge ✅ dengan source code visible!

⚠️ Already Verified Error:

Jika contract sudah pernah diverify, Anda akan melihat:

Contract [src/SimpleBank.sol:SimpleBank] "0x108872F713A27bc22ca1db8CEefCAC8CbeDdF9E5" is already verified. Skipping verification.

Ini normal! Contract identik tidak perlu diverify ulang.

Blockscout Features:

✅ No API key needed
✅ Instant verification
✅ Better UI dengan code reader
✅ Contract interaction tools built-in
✅ Real-time verification status dengan --watch

🧪 Test Deployed Contract

Use Cast to Interact

1. Read balance:

cast call 0xYourContractAddress "balances(address)" 0xYourWalletAddress --rpc-url $LISK_SEPOLIA_RPC_URL

2. Deposit ETH:

cast send 0xYourContractAddress "deposit()" \
    --value 0.01ether \
    --private-key $PRIVATE_KEY \
    --rpc-url $LISK_SEPOLIA_RPC_URL

Output:

blockHash               0xabc...
blockNumber             5123457
from                    0xYourAddress
gasUsed                 45123
status                  1 (success)
transactionHash         0xdef...

3. Check balance again:

cast call 0xYourContractAddress "balances(address)" 0xYourWalletAddress --rpc-url $LISK_SEPOLIA_RPC_URL

# Convert hex to decimal
cast to-dec 0x002386f26fc10000
# Output: 10000000000000000 (0.01 ETH in wei)

4. Withdraw:

cast send 0xYourContractAddress "withdraw(uint256)" 5000000000000000 \
    --private-key $PRIVATE_KEY \
    --rpc-url $LISK_SEPOLIA_RPC_URL

💡 Alternative: Gunakan Blockscout UI untuk interact dengan contract secara visual!

https://sepolia-blockscout.lisk.com/address/0xYourContractAddress#write-contract

✅ Production Deployment Checklist

Pre-Deployment

Code Review:

Gas Optimization:

Gas report reviewed
Optimizations applied
Gas snapshots compared
Contract size < 24KB

Documentation:

NatSpec comments complete
README with contract description
Deployment guide written

Deployment

Environment:

Private key secured (hardware wallet for mainnet!)
RPC endpoint reliable
Sufficient ETH for gas
Gas price checked (don't overpay!)

Deployment Process:

Dry run successful
Deployment script tested on testnet first
Deploy transaction confirmed
Contract address saved securely

Post-Deployment:

Contract verified on Blockscout
Source code visible & matches
Initial smoke tests passed
Contract ownership renounced/transferred (if applicable)

Mainnet Additional Steps

Security:

Professional audit completed
Audit issues resolved
Multi-sig for admin functions
Timelocks for upgrades (if upgradeable)
Bug bounty program (for large contracts)

Monitoring:

Events monitoring setup
Alert system for critical functions
Gas price tracker
Frontend integration tested

Documentation:

User guide published
Developer documentation
Contract addresses listed
Emergency procedures documented

🎯 Best Practices Summary

Gas Optimization

✅ Use uint256 for most variables
✅ Cache storage variables in memory
✅ Use custom errors instead of require strings
✅ Use calldata for read-only parameters
✅ Use external instead of public when possible
✅ Use unchecked for safe arithmetic
✅ Use events instead of storage for history
✅ Short-circuit boolean conditions
✅ Use ++i instead of i++ in loops
✅ Pack variables into slots when possible

Testing

✅ Write tests BEFORE deployment
✅ Aim for 100% coverage
✅ Test happy paths & edge cases
✅ Use fuzz testing
✅ Test on testnet before mainnet

Deployment

✅ Use deployment scripts
✅ Verify contracts on Blockscout (no API key needed!)
✅ Test deployed contract
✅ Document everything
✅ Security audit for mainnet

📚 Foundry Commands Reference

# Building
forge build                          # Compile contracts
forge build --sizes                  # Show contract sizes
forge clean                          # Clean build artifacts

# Testing
forge test                           # Run all tests
forge test -vvvv                     # Verbose output
forge test --gas-report              # Show gas usage
forge test --match-test <name>       # Run specific test
forge coverage                       # Test coverage

# Gas Analysis
forge snapshot                       # Create gas snapshot
forge snapshot --diff <file>         # Compare snapshots

# Deployment (Lisk Sepolia)
# Opsi 1: Simple deployment dengan forge create (Recommended)
forge create --rpc-url $LISK_SEPOLIA_RPC_URL \
    --etherscan-api-key 123 \
    --verify \
    --verifier blockscout \
    --verifier-url https://sepolia-blockscout.lisk.com/api \
    --private-key $PRIVATE_KEY \
    src/Contract.sol:ContractName

# Opsi 2: Complex deployment dengan forge script
forge script script/Deploy.s.sol --rpc-url $LISK_SEPOLIA_RPC_URL --broadcast

# Manual Verification
forge verify-contract <address> \
    src/Contract.sol:ContractName \
    --chain 4202 \
    --watch \
    --verifier blockscout \
    --verifier-url https://sepolia-blockscout.lisk.com/api

# Interaction (Cast)
cast call <address> "func()"         # Call view function
cast send <address> "func()" --private-key <key> # Send transaction
cast balance <address>               # Get balance
cast to-dec <hex>                    # Convert hex to decimal
cast to-wei <amount> <unit>          # Convert to wei

# Utilities
forge inspect <contract> abi         # Show ABI
forge inspect <contract> bytecode    # Show bytecode
forge fmt                            # Format Solidity code
forge doc                            # Generate documentation

🎓 Final Summary

Apa yang sudah dipelajari:

✅ Gas Optimization:

10+ optimization techniques
Gas savings measurement
Before/after comparison
10-12% gas reduction achieved

✅ Deployment:

Deployment scripts di Solidity
Deploy to Lisk Sepolia testnet
Auto-verification on Blockscout (no API key!)
Contract interaction with cast
97% cheaper gas fees vs Ethereum

✅ Best Practices:

Pre-deployment checklist
Testing requirements
Security considerations
Production-ready workflow

Your SimpleBank contract:

✅ Fully tested (100% coverage)
✅ Gas optimized (10-12% savings)
✅ Deployed to Lisk Sepolia
✅ Verified on Blockscout
✅ 97% cheaper gas fees
✅ Production ready!

🏆 Congratulations!

Anda sudah menguasai Foundry! 🎉

Skills acquired:

⚡ Foundry suite (forge, cast, anvil, chisel)
🔨 Smart contract development
🧪 Comprehensive testing in Solidity
🎲 Fuzz testing for edge cases
⚡ Gas optimization techniques
🚀 Professional deployment workflow
🔍 Contract verification

You can now:

Build production-grade smart contracts
Write comprehensive test suites
Optimize gas efficiently
Deploy confidently to mainnet
Contribute to DeFi protocols
Participate in audit contests

🚀 Next Steps

Continue Learning:

Advanced Foundry:

Invariant testing
Symbolic execution with Halmos
Gas profiling with forge geiger
Multi-contract deployments

Security:

Smart contract security patterns
Common vulnerabilities (reentrancy, overflow, etc.)
Audit tools (Slither, Mythril, Echidna)
Participate in Code4rena/Sherlock

DeFi:

DEX mechanics (Uniswap-style)
Lending protocols (Aave-style)
Staking & rewards
Governance tokens

Resources:

Foundry Book - Official Foundry documentation
Lisk Developer Docs - Official Lisk deployment guide
Lisk Sepolia Blockscout - Block explorer & contract verification
Solidity by Example - Learn Solidity patterns
Smart Contract Security - Security best practices
Ethereum Jakarta Discord - Community support

🙏 Thank You!

Terima kasih sudah mengikuti workshop Foundry!

Feedback & Questions:

Ethereum Jakarta Telegram
Foundry Discord
GitHub Issues

Keep Building! 🔨⚡

📚 Official Documentation Compliance

Workshop ini menggunakan commands yang sesuai dengan:

✅ Lisk Official Documentation

Deployment: forge create dengan Blockscout verification
Verification: forge verify-contract dengan --chain 4202 dan --watch
Reference: https://docs.lisk.com/building-on-lisk/deploying-smart-contract

✅ Foundry Best Practices

Modern ESM & TypeScript setup
Gas optimization techniques
Comprehensive testing approach
Reference: https://book.getfoundry.sh

✅ Blockscout Integration

No API key needed
Real-time verification monitoring
Contract interaction tools
Reference: https://sepolia-blockscout.lisk.com

← Back to Main Page

#BuildWithFoundry | #BuildOnLisk | #EthereumJakarta | #Web3Indonesia

🎯 Tujuan Module​

💡 Why Gas Optimization Matters?​

Analogi: Gas = Biaya Bensin​

Real Examples:​

📊 Measure Current Gas Usage​

Step 1: Run Gas Report​

Step 2: Create Gas Snapshot​

⚡ Gas Optimization Techniques​

Technique 1: Use uint256 Instead of Smaller Types​

Technique 2: Caching Storage Variables​

Technique 3: Use Custom Errors Instead of require Strings​

Technique 4: Use calldata Instead of memory for Read-Only Parameters​

Technique 5: Use ++i Instead of i++ in Loops​

Technique 6: Short-Circuit with && and ||​

Technique 7: Use Events Instead of Storage for Historical Data​

🔄 Optimize SimpleBank Contract​

Create SimpleBankOptimized.sol​

📊 Compare Gas Usage​

Run Gas Comparison​

Snapshot Comparison​

🚀 Deployment Scripts​

Create Deployment Script​

🌐 Deploy to Lisk Sepolia Testnet​

Step 1: Setup Environment Variables​

Step 2: Load Environment Variables​

Step 3: Deploy to Lisk Sepolia​

Opsi 1: forge create (Recommended - Simple & Fast)​

Opsi 2: forge script (Advanced - For Complex Deployments)​

Step 4: Expected Output​

Output dari forge create (Opsi 1):​

🔍 Verify Contract Manually​

🧪 Test Deployed Contract​

Use Cast to Interact​

✅ Production Deployment Checklist​

Pre-Deployment​

Deployment​

Mainnet Additional Steps​

🎯 Best Practices Summary​

Gas Optimization​

Testing​

Deployment​

📚 Foundry Commands Reference​

🎓 Final Summary​

🏆 Congratulations!​

🚀 Next Steps​

Continue Learning:​

Resources:​

🙏 Thank You!​

📚 Official Documentation Compliance​

🎯 Tujuan Module

💡 Why Gas Optimization Matters?

Analogi: Gas = Biaya Bensin

Real Examples:

📊 Measure Current Gas Usage

Step 1: Run Gas Report

Step 2: Create Gas Snapshot

⚡ Gas Optimization Techniques

Technique 1: Use `uint256` Instead of Smaller Types

Technique 2: Caching Storage Variables

Technique 3: Use Custom Errors Instead of require Strings

Technique 4: Use `calldata` Instead of `memory` for Read-Only Parameters

Technique 5: Use `++i` Instead of `i++` in Loops

Technique 6: Short-Circuit with `&&` and `||`

Technique 7: Use Events Instead of Storage for Historical Data

🔄 Optimize SimpleBank Contract

Create SimpleBankOptimized.sol

📊 Compare Gas Usage

Run Gas Comparison

Snapshot Comparison

🚀 Deployment Scripts

Create Deployment Script

🌐 Deploy to Lisk Sepolia Testnet

Step 1: Setup Environment Variables

Step 2: Load Environment Variables

Step 3: Deploy to Lisk Sepolia

Opsi 1: forge create (Recommended - Simple & Fast)

Opsi 2: forge script (Advanced - For Complex Deployments)

Step 4: Expected Output

Output dari `forge create` (Opsi 1):

🔍 Verify Contract Manually

🧪 Test Deployed Contract

Use Cast to Interact

✅ Production Deployment Checklist

Pre-Deployment

Deployment

Mainnet Additional Steps

🎯 Best Practices Summary

Gas Optimization

Testing

Deployment

📚 Foundry Commands Reference

🎓 Final Summary

🏆 Congratulations!

🚀 Next Steps

Continue Learning:

Resources:

🙏 Thank You!

📚 Official Documentation Compliance