Tenderly Integration (Transaction Debugging)
A transaction reverted with "execution reverted" — and that's all Etherscan shows. Without stack tracing, it's unclear which exact line in the contract caused the revert, what variable values were at that moment, through what call chain we reached the error. Tenderly solves this: complete EVM execution tracing, debugging like in a regular debugger, with breakpoints and state inspection.
What Tenderly Offers
Transaction Simulator — reproduction of any historical transaction with parameter modifications. Want to check what would have happened if the user sent 10% more slippage? Or replay a transaction in mainnet state at a specific block? Simulator allows this without real funds.
Visual Debugger — step-by-step execution with stack, memory, storage inspection on each opcode. For a Solidity developer, this is like gdb, but for EVM. Especially valuable when analyzing complex reverts in multi-contract calls — you see the exact source line if contract is verified.
Tenderly Forks — sandbox based on mainnet fork. Deploy contracts, execute transactions in isolated environment with real mainnet state (real Uniswap pools, real Aave positions). This is faster than anvil --fork-url for interactive debugging, and more convenient for team collaboration.
Alerts & Monitoring — triggers on contract events, storage changes, specific functions. Can set webhook to Discord/Slack on every Transfer token event or when TVL changes by more than X%.
Web3 Actions — serverless TypeScript functions that respond to on-chain events. For example: upon detecting large transaction, automatically pause contract via multisig.
Integration into Project
Tenderly SDK is installed via npm and integrates with Hardhat. In hardhat.config.ts add @tenderly/hardhat-tenderly plugin, after which deploy scripts automatically verify and push contracts to Tenderly Dashboard.
import * as tenderly from "@tenderly/hardhat-tenderly";
tenderly.setup({ automaticVerifications: true });
For Foundry — manual verification via CLI: forge verify-contract --chain mainnet --etherscan-api-key $TENDERLY_ACCESS_KEY.
Most valuable integration — using Tenderly Forks in tests. Instead of hardhat node --fork, fork is created via Tenderly API, and all transactions are automatically traced. When test fails — immediately get link to Debug UI with full tracing.
What Tenderly Doesn't Replace
Tenderly doesn't replace Slither/Mythril for static analysis and doesn't replace Echidna for fuzzing. This is a tool for debugging and monitoring already written code, not for finding vulnerabilities during development. In our stack, Tenderly lives alongside Foundry tests, not instead of them.
Basic integration (plugin + auto-verification + first alerts) — 1 day. Setting up complete monitoring with Web3 Actions — 2-3 days.