proxmox/docs/06-besu/COMPILATION_RECOMMENDATIONS.md

# Compilation Recommendations for Large Contract Project

**Last Updated:** 2026-01-31  
**Document Version:** 1.0  
**Status:** Active Documentation

---

**Date**: 2025-01-19  
**Issue**: Compilation timing out for 266 contract files  
**Status**: Recommendations provided

---

## Problem Analysis

### Current Situation
- **Total files**: 266 Solidity files
- **Contract files**: 148 contracts
- **Deployment scripts**: 10+ scripts
- **Compilation**: Timing out (30 minute timeout exceeded)
- **Configuration**: `via_ir = true`, `optimizer = true`, `optimizer_runs = 200`

### VM Resources
- **Memory**: 16GB (5.3GB used, 8.9GB free, 10GB available)
- **CPU**: 4 cores
- **Disk**: 196GB (5.6GB used, 181GB free)

**Resources are sufficient** - the issue is compilation strategy, not resources.

---

## Recommendations

### 1. Compile Only What's Needed for Deployment (RECOMMENDED)

Instead of compiling all 266 files, compile only the contracts needed for the specific deployment scripts.

#### Strategy A: Compile by Deployment Script

```bash
# Compile only WETH9 Bridge contracts
forge build --force script/DeployCCIPWETH9Bridge.s.sol

# Compile only WETH10 Bridge contracts  
forge build --force script/DeployCCIPWETH10Bridge.s.sol

# Compile only LINK deployment
forge build --force script/DeployLinkToCanonicalAddress.s.sol
```

#### Strategy B: Use Selective Import Compilation

Foundry automatically compiles only what's needed for each script, but you can help it by:

```bash
# Compile with explicit script
forge script script/DeployCCIPWETH9Bridge.s.sol:DeployCCIPWETH9Bridge --dry-run

# This will compile only what's needed
```

### 2. Optimize Compiler Settings for Faster Compilation

Create a compilation profile optimized for speed vs. gas optimization:

```toml
[profile.fast]
optimizer = true
optimizer_runs = 1  # Minimal optimization for faster compilation
via_ir = false  # Disable IR for faster compilation (if no stack too deep errors)
```

Usage:
```bash
forge build --profile fast
```

**Trade-off**: Larger bytecode, more gas, but much faster compilation.

### 3. Increase Memory Limits

Set higher memory limits for Solidity compiler:

```toml
[profile.default]
solc = "0.8.20"
optimizer = true
optimizer_runs = 200
via_ir = true

# Add memory settings
[evm]
memory_limit = "1gb"  # Increase if needed
```

### 4. Compile in Stages

Break compilation into stages:

```bash
# Stage 1: Compile core contracts only
forge build --force contracts/bridge/trustless/

# Stage 2: Compile bridge contracts
forge build --force contracts/bridge/

# Stage 3: Compile deployment scripts
forge build --force script/
```

### 5. Use Incremental Compilation

Leverage Foundry's incremental compilation by not using `--force`:

```bash
# First compilation (may take longer)
forge build

# Subsequent compilations (only changed files)
forge build  # Much faster
```

### 6. Compile Deployment Scripts Only

For deployment purposes, you only need the deployment scripts compiled:

```bash
# Compile deployment scripts and their dependencies only
forge build script/DeployCCIPWETH9Bridge.s.sol script/DeployCCIPWETH10Bridge.s.sol script/DeployLinkToCanonicalAddress.s.sol
```

### 7. Adjust Optimizer Settings

Reduce optimizer runs for faster compilation:

```toml
[profile.deploy]
optimizer = true
optimizer_runs = 100  # Reduced from 200 for faster compilation
via_ir = true
```

### 8. Split Compilation with Cache

Use Foundry's cache more effectively:

```bash
# Clear cache first (fresh start)
forge clean

# Compile with explicit output
forge build --force --sizes

# This shows sizes and helps identify large contracts
```

---

## Recommended Approach for Deployment

### Option 1: Compile Script-Specific (FASTEST)

```bash
# In VM
cd /home/intlc/projects/proxmox/smom-dbis-138

# Compile and deploy WETH9 Bridge (only compiles what's needed)
forge script script/DeployCCIPWETH9Bridge.s.sol:DeployCCIPWETH9Bridge \
  --rpc-url http://localhost:8545 \
  --broadcast \
  --private-key $PRIVATE_KEY \
  --slow

# Compile and deploy WETH10 Bridge
forge script script/DeployCCIPWETH10Bridge.s.sol:DeployCCIPWETH10Bridge \
  --rpc-url http://localhost:8545 \
  --broadcast \
  --private-key $PRIVATE_KEY \
  --slow

# Compile and deploy LINK
forge script script/DeployLinkToCanonicalAddress.s.sol:DeployLinkToCanonicalAddress \
  --rpc-url http://localhost:8545 \
  --broadcast \
  --private-key $PRIVATE_KEY \
  --slow
```

**Advantage**: Only compiles what each script needs, much faster.

### Option 2: Two-Stage Compilation

```bash
# Stage 1: Compile with fast profile (if created)
forge build --profile fast  # Or compile incrementally without --force

# Stage 2: Deploy using deployment script
bash scripts/deploy-all-bridges-standalone.sh
```

### Option 3: Update Deployment Script to Compile Per Script

Modify `deploy-all-bridges-standalone.sh` to compile before each deployment:

```bash
# Before each forge script command, add:
echo "Compiling contracts for WETH9 Bridge..."
forge build script/DeployCCIPWETH9Bridge.s.sol --force 2>&1 | tail -10
```

---

## Compiler Settings Comparison

| Setting | Current | Fast Profile | Deploy Profile |
|---------|---------|--------------|----------------|
| optimizer | true | true | true |
| optimizer_runs | 200 | 1 | 100 |
| via_ir | true | false | true |
| Speed | Slow | Fast | Medium |
| Gas | Optimized | High | Medium |
| Use Case | Production | Development | Deployment |

---

## Implementation Steps

### Step 1: Create Fast Compilation Profile

Add to `foundry.toml`:
```toml
[profile.fast]
optimizer = true
optimizer_runs = 1
via_ir = false
```

### Step 2: Update Deployment Script

Modify deployment script to use selective compilation or fast profile.

### Step 3: Test Compilation

```bash
# Test fast compilation
forge build --profile fast

# Verify it completes within timeout
# Then use for deployment
```

---

## Alternative: Compile Locally and Copy

If VM compilation continues to timeout:

1. **Compile on local system** (which has more resources potentially)
2. **Copy compiled artifacts** to VM:
   ```bash
   # On local system
   cd smom-dbis-138
   forge build --force
   
   # Copy out/ and cache/ to VM
   tar czf compiled-artifacts.tar.gz out/ cache/
   scp compiled-artifacts.tar.gz root@192.168.11.10:/tmp/
   
   # In VM
   cd /home/intlc/projects/proxmox/smom-dbis-138
   tar xzf /tmp/compiled-artifacts.tar.gz
   ```

3. **Deploy using pre-compiled artifacts**

---

## Recommended Solution for Current Deployment

**For immediate deployment**, use **Option 1: Script-Specific Compilation**:

```bash
# Each forge script command will compile only what's needed
forge script script/DeployCCIPWETH9Bridge.s.sol:DeployCCIPWETH9Bridge \
  --rpc-url http://localhost:8545 \
  --broadcast \
  --private-key $PRIVATE_KEY \
  --slow \
  -vvv
```

This avoids the need to compile all 266 files upfront.

---

## Monitoring Compilation Progress

```bash
# Watch compilation progress
forge build --force 2>&1 | tee compilation.log

# In another terminal, monitor
tail -f compilation.log | grep -E "Compiling|Error|Success"
```

---

**Status**: Recommendations ready for implementation  
**Next**: Update deployment strategy to use script-specific compilation