Pre-Deployment Checklist

Back to Production Readiness

1. Compile with Production Settings

Use the strictest compilation flags:

neo-solc contract.sol \
  -I devpack \
  -O3 \
  --callt \
  --deny-wildcard-contracts \
  --deny-wildcard-methods \
  --json-errors \
  --json-warnings \
  -o build/contract

Flags explained:

Flag	Purpose
-O3	Maximum optimization for smallest bytecode and lowest execution cost
--callt	Use CALLT instructions for efficient native contract calls
--deny-wildcard-contracts	Reject wildcard contract permissions
--deny-wildcard-methods	Reject wildcard method permissions
--json-errors	Structured error output for CI parsing
--json-warnings	Structured warning output for CI parsing

2. Audit the Manifest

Inspect every field of the generated manifest:

# Full manifest
jq '.' build/contract.manifest.json

# Contract name
jq '.name' build/contract.manifest.json

# Permissions -- should NOT contain wildcards
jq '.permissions' build/contract.manifest.json

# Supported standards
jq '.supportedstandards' build/contract.manifest.json

# Method signatures
jq '.abi.methods[] | {name, parameters: [.parameters[].type], returntype, safe}' \
  build/contract.manifest.json

# Events
jq '.abi.events[] | {name, parameters: [.parameters[].type]}' \
  build/contract.manifest.json

# Trust settings
jq '.trusts' build/contract.manifest.json

Permission Audit Guide

Review each permission entry:

jq '.permissions[] | {contract, methods}' build/contract.manifest.json

For each entry, verify:

• contract is a specific hash (e.g., 0xef4073a0f2b305a38ec4050e4d3d28bc40ea63f5), not *.
• methods is a specific list (e.g., ["transfer", "balanceOf"]), not *.
• Every listed method is actually called by your contract.
• No unnecessary permissions are included.

If the compiler cannot narrow permissions (e.g., due to dynamic calls), provide an explicit allowlist:

neo-solc contract.sol \
  -I devpack \
  --manifest-permissions permissions.json \
  --manifest-permissions-mode replace-wildcards \
  --deny-wildcard-contracts \
  --deny-wildcard-methods \
  -o build/contract

3. Verify the NEF

Check the NEF file size and structure:

# File size
ls -la build/contract.nef

# Verify NEF magic bytes (should start with 4E 45 46 33)
xxd build/contract.nef | head -1

Optionally inspect the NeoVM assembly:

neo-solc contract.sol -I devpack -O3 -f assembly -o build/contract.asm
cat build/contract.asm

4. Predict the Contract Hash

If you need to know the contract hash before deployment (e.g., for cross-contract references):

neo-solc contract.sol \
  -I devpack \
  -O3 \
  --deployer 0x<your-deployer-scripthash> \
  -o build/contract

The compiler prints the predicted hash. Verify it matches your expectations.