Tenderly

Tenderly is a managed platform for simulating, debugging, deploying, monitoring, and operating EVM-based systems. Its core strength is testing an intended transaction or deployment against selected chain state before it reaches the public network, then retaining tools for understanding and observing what happens after deployment.

Simulation makes state effects visible before broadcast

The Simulator can rerun an existing transaction from its original block and timestamp or execute a new call with chosen network, sender, gas, value, calldata, and state overrides. Results can include decoded output, gas use, events, state changes, token transfers, fund flow, and gas-profiler information.

A simulation bundle runs up to five transactions in sequence with shared state. That makes dependent actions such as an approval followed by a transfer testable as one scenario instead of unrelated calls. Source edits and per-step cheatcodes extend the same approach to proposed changes without altering public-chain state.

Transaction debugging follows the actual call path

Tenderly’s debugger starts with a transaction and shows its execution trace, source code, stack trace, decoded calls, opcodes, inputs and outputs, callers, balances, and function-level gas data. After a revert or unexpected onchain result, that connects the visible outcome to the nested calls that produced it.

Tenderly also supplies Node RPC across supported EVM networks and links ordinary RPC use with simulation, gas estimation, tracing, and custom-RPC features. Alerts watch selected targets and events, then notify configured destinations or trigger automated response flows, extending the platform into production observation.

Shared virtual environments instead of a purely local node

Virtual Environments are private EVM forks with public JSON-RPC access and an Admin RPC for balances, storage, time, bytecode, and synchronization. They can stay fixed at a fork block, synchronize selected storage until local changes occur, or replay parent-network blocks in Network Mirror mode.

Foundry’s Anvil is the close local alternative: it provides an in-memory node and chain forks for terminal-first contract work. Tenderly adds persistent shared forks, selectable synchronization, dashboard-led diagnosis, and operations tooling, but it is not primarily a Solidity compiler or a tool for structuring a contract repository.