Analyse Gas Usage in Starknet Transactions with Walnut Flamegraphs
If you've ever looked at a Starknet transaction and wondered where all the gas goes — we’ve got the answer.

Cairo Developers use Walnut to discover and fix bugs in their Smart Contracts.
“Transaction Debugging and Simulations are a big missing piece on Starknet, so it’s great to see Walnut providing developers with these essential tools.”
“Debugger and transaction simulator is a big missing piece in Starknet. At Argent, we are excited that this gap is being filled with Walnut.”
“Debugging or simulating transactions is an absolutely critical task for any on-chain developer. We cannot wait to have Walnut integrated with Karnot and Madara Appchains.”
“Debugging transactions and performance monitoring are pain points on Starknet today. Every DeFi protocol builder woud benefit from better tooling, and it’s great to see Walnut addressing this need.”
“I think Walnut is very important and that you [the Walnut team] are doing very valuable work for Starknet.”
“Walnut is an essential tool for debugging complex transactions with nested calls and large amounts of calldata. Walnut helped me with a massive blocker on the Bitcoin inscriptions project. 🌰”
“At Cartridge, we see a lot of interest in transaction debugging and simulation. Walnut has the potential to become a critical tool for game developers building on Starknet.”
“With Enso, we are not yet on Starknet. However, seeing a debugger and simulator like Walnut is a great testament to Starknet’s maturing devtools ecosystem, making it more appealing to new developers. We need a debugger and simulator to ship anything on Starknet, as we rely on this tooling in all EVM ecosystems and cannot build without it.”
“We are thrilled about the Walnut integration with Dojo. Step-by-step debugging with instant replay of transactions will be another string to the bow for all the sensei building on Dojo.”
“At Nimbora, we are big supporters of Walnut and the transaction debugger and simulator for Starknet. We are looking forward to using it with Nimbora and integrating it with Devnet and Rivet, our new developer-focused wallet.”
“Had to debug an OpenZeppelin tx on Starknet Sepolia—Walnut made it way too easy. Lifesaver!”
If you've ever looked at a Starknet transaction and wondered where all the gas goes — we’ve got the answer.
Starknet is an ecosystem that made a bold decision: it launched with its own custom language—Cairo. That means, among other things, it had to build everything from scratch. Cairo devs couldn’t rely on any of the existing blockchain tooling available for Solidity, Ethereum, or other blockchain ecosystems.
Walnut Labs is partnering with Offchain Labs—the team behind Arbitrum—to improve the debugging experience across the Arbitrum stack. This effort is part of our broader mission to bring modern debugging and monitoring tools to emerging rollup ecosystems.