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Rumble Fish presents EVM Debugger - the ultimate tool for Defi developers

Rumble Fish presents EVM Debugger - the ultimate tool for Defi developers

Mon, Jun 12, 20234 min read

Category: Code Stories / Blockchain

We proudly present our newest tool for all Ethereum and Defi developers that want to write better, more effective, and optimized Ethereum smart contracts. EVM Debugger is a tool that will help you become a master in writing smart contracts. And it’s completely free!

Unexplainable failures of EVM transactions - if you’re a smart contract developer it’s safe to assume you’ve suffered at some point. When this happens, you usually open Etherscan and try to find where your smart contract went astray. Maybe you can retry your transaction with eth_call and get a useful message? Or maybe trace output will help you? Imagine having a tool that performs these debugging steps for you and presents you with the most detailed information about logs, state changes, storage updates, gas usage, and most importantly, revert messages for each of the internal transactions! Our EVM Debugger collects and showcases all the information about a single Ethereum transaction so you can easily identify its pain points and improve your smart contract writing skills.  

How does it work?

All you need to start is a transaction hash that you simply paste into the tool, then you choose the network, and click “Process log”. After a couple of minutes, you’ll get a full analysis of the transaction.

All of the data is organized in a very user-friendly and intuitive way. You get 3 main sections: 

  • Data Manager

From here you can access source codes (if available), bytecode, and ABIs. 

  • Transaction Screen

Shows you the trace information (address, status, type, block number, passed gas, gas cost, and value), trace tree, call-specific data, events data, and storage data 

  • Structlog Explorer

Displays the trace, EVM steps, disassembled bytecode, and step information. 

The visual graph on the transaction screen lets you know how the gas consumption was divided, and which step was the most expensive one. It’s a great tool for optimizing your future smart codes.

Why should you use it?

EVM Debugger is a unique and free solution designed specifically for EVM and Defi developers. It makes EVM smart contract analysis easy and user-friendly, providing developers with detailed information about transactions in one simple step. With EVM Debugger, you can smoothly access all the details regarding a single Ethereum transaction, making it the only debugger you’ll need.

With EVM Debugger you’ll be able to easily find errors in your smart contracts as well as optimize them for lower gas usage. It’s also a great learning tool for less seasoned Defi developers as it gives a lot of insights into how EVM works at its most basic level. 

The tool currently supports networks such as Ethereum, Goerli, Polygon, Mumbai, and Sepolia, with more on the way. Our team is constantly improving the Debugger, adding new features, and collecting feedback from its users. EVM Debugger is a completely free solution, made for developers by developers. To try it, please visit

Why did we create it?

At Rumble Fish, we constantly expand our blockchain and Defi knowledge, but we do not gatekeep it. We like to share it with broader communities as we believe in the power of open-source projects and the importance of knowledge sharing. That’s why, as blockchain pros, we decided to make EVM Debugger free for everyone. For the same reason, we created another tool called KMS Signer that derives addresses and signs transactions using the AWS KMS (Key Management Service) solution. Stay tuned for our future projects!

{{blogPost,Privatizing the private key in blockchain development with KMS Provider}}

Marek Kowalski
Marek Kowalski

CTO / Co-Founder

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