This document outlines security best practices and checklist items for Callora vault contracts to improve audit readiness and reviewer confidence.

• All privileged functions protected by onlyOwner / role-based access
• No public or external access to admin functions
• Ownership transfer tested and documented

• No integer overflow/underflow possible
• Solidity ^0.8.x overflow checks relied upon or SafeMath used where required
• For Soroban/Rust: checked_add / checked_sub used for all balance mutations
• overflow-checks enabled in both dev and release profiles

• Initializer protected against multiple calls
• Upgradeable patterns use initializer guards
• No unprotected re-init functions
• init validates all input parameters (rejects negative values where appropriate)

• Emergency pause mechanism implemented
• Paused state blocks fund movement
• Pause/unpause flows tested

• Ownership transfer is two-step (optional but recommended)
• Ownership transfer emits events
• Renounce ownership reviewed and justified

• Checks-effects-interactions pattern followed
• Reentrancy protection where external calls exist
• No untrusted delegatecalls
• Token transfers use safe transfer patterns

• Deposit/withdraw invariants tested
• Vault balance accounting verified
• Funds cannot be locked permanently
• Minimum deposit requirements enforced
• Maximum deduction limits enforced
• Revenue pool transfers validated
• Batch operations respect individual limits

• All amounts validated to be > 0
• Address/parameter validation on all public functions
• Boundary conditions tested (max values, zero values)
• Error messages provide clear context for debugging

• All state changes emit appropriate events
• Event schema documented and indexed
• Critical operations (deposit, withdraw, deduct) logged with full context

• Unit tests cover all public functions
• Edge cases and boundary conditions tested
• Panic scenarios tested with #[should_panic]
• Integration tests for complete user flows
• Minimum 95% test coverage maintained

Before any mainnet deployment:

• Engage an independent third-party security auditor

  • Choose auditors with experience in Soroban/Stellar smart contracts
  • Ensure auditor understands vault-specific risk patterns

• Perform a full smart contract audit

  • Review all contract code for security vulnerabilities
  • Analyze upgrade patterns and migration paths
  • Validate mathematical correctness of balance operations

• Address all high and medium severity findings

  • Create tracking system for audit findings
  • Implement fixes for all H/M severity issues
  • Document rationale for any low severity findings that won't be fixed

• Publish audit report for transparency

  • Make audit report publicly available
  • Include summary of findings and remediation steps
  • Provide evidence of test coverage and validation

• WASM compilation verified and reproducible
• Stellar network parameters validated (fees, limits)
• Cross-contract call security reviewed
• Storage patterns optimized and secure

• Fee structures reviewed for economic attacks
• Revenue pool distribution validated
• Maximum loss scenarios analyzed
• Slippage and market impact considered

• Deployment process documented and automated
• Key management procedures established
• Monitoring and alerting configured
• Incident response plan prepared

• Stellar Security Best Practices
• Soroban Documentation
• Smart Contract Weakness Classification Registry

Note: This checklist should be reviewed and updated regularly as new security patterns emerge and the codebase evolves.