Security & Operational Guidance

Evix is designed with minimal surface area and on-chain enforcement. This page covers best practices for secure integration.

On-Chain Protections

The Evix contract enforces safety checks at the contract level - these cannot be bypassed by the SDK or caller:

Protection	Mechanism	Error
Deadline enforcement	Reverts if block.timestamp > deadline	DeadlineExceeded()
Slippage protection	Reverts if output < minAmountOut	InsufficientOutput(amountOut, minAmountOut)
Input validation	Reverts if amountIn == 0	InvalidAmountIn()
Recipient validation	Reverts if recipient == address(0)	InvalidRecipient()
Pair access control	Reverts if pair not allowlisted	UnsupportedPair(tokenIn, tokenOut)

Best Practices

Always set minAmountOut

Never use minAmountOut: 0 in production transactions. This leaves the swap completely unprotected against price movement and MEV. Set this value based on your own pricing model or oracle data.

// Bad - no slippage protection
const result = await evix.swap({
  ...params,
  minAmountOut: 0n, // DANGEROUS in production
});

// Good - integrator sets minAmountOut from their own pricing
const result = await evix.swap({
  ...params,
  minAmountOut: 995_000n, // determined by integrator
});

Use tight deadlines

Short deadlines prevent stale transactions from landing in unfavorable conditions.

Use Case	Recommended Deadline
Trading bots	15–30 seconds
Backend services	30–60 seconds
User-facing flows	60–120 seconds

Validate recipients

Ensure the recipient address is correctly derived and never user-controlled without validation. A malicious or incorrect recipient means tokens are sent to the wrong address with no recourse.

Maintain deployment mappings

For multi-chain or multi-customer systems, maintain explicit configuration:

const deployments: Record<string, EvixDeployment> = {
  "customer-a-base": {
    chainId: 8453,
    contractAddress: "0x...",
    supportedPairs: [["0x...", "0x..."]],
  },
  "customer-a-arbitrum": {
    chainId: 42161,
    contractAddress: "0x...",
    supportedPairs: [["0x...", "0x..."]],
  },
};

Operational Guidance

Token Approvals

Before swapping, the Evix contract must be approved to spend tokenIn:

// Approve exact amount (recommended)
await walletClient.writeContract({
  address: tokenIn,
  abi: erc20Abi,
  functionName: "approve",
  args: [evixAddress, amountIn],
});

tip

Consider using exact approvals rather than type(uint256).max to minimize approval surface.

Error Handling

Handle all revert cases explicitly:

try {
  const result = await evix.swap(params);
} catch (error) {
  if (error.message.includes("DeadlineExceeded")) {
    // Transaction was too slow - consider shorter deadlines
  } else if (error.message.includes("InsufficientOutput")) {
    // Price moved beyond tolerance - adjust minAmountOut and retry
  } else if (error.message.includes("UnsupportedPair")) {
    // Pair not enabled on this deployment - check configuration
  }
}

Monitoring

For production integrations, monitor:

• Swap events - Track execution via the Swap event
• Revert rates - High revert rates indicate stale pricing or tight tolerances
• Gas costs - Monitor gas consumption across chains