Hi, it's Tobi. Our vision is provide cross chain bridge a trust-less and privacy service.

Our goal is to enable seamless and secure transactions between different blockchain networks, without the need for intermediaries or centralized exchanges. With our innovative Hashed Time-Locked Contracts (HTLC) technology, users can enjoy fast, reliable, and private transactions, while maintaining full control over their assets. Our mission is to empower individuals and businesses to participate in the decentralized economy, and to drive the adoption of blockchain technology worldwide.


Tobi-core: Tobi is a Sparse Merkle tree (SMT) deployed on StarkNet (devnet and Madara). We use Cairo to generate the tree proof and verify the hash as a layer 3 for all chains. In the future, we plan to use Celestia as a verification layer. Additionally, we use Solidity to write our HTLC smart contracts. We use nethermind contract to tran-compile the HTLC contract and deploy on starknet devnet too. Our use of SMTs allows for efficient and secure storage of transaction data, while our integration with StarkNet enables fast and low-cost transactions. By leveraging these cutting-edge technologies, we aim to provide a seamless and secure cross-chain bridge service for our users.

Frontend: Tobi frontend using chakra-ui component to provide beautiful view. And for better experience from query chain data. Our dashborad using checkpoint and the graph to query all chains data for better user experience.

Project Architechure

Step 1. User can deposit their token in our HTLC contract. 

Step 2. Get the ticket when transaction confirmed.

Step 3. Using off-chain and Cairo contract to generate the proof by using this ticket.

Step 4. Get the proof and withdraw money from other chain.

Demo Link

Tree service only live in starknet devnet and sharingan, you need to deployed your own or wait for this update.

Tobi frontend:

Tobi Demo:

Our Tech Stack (Sponsor Tech)

Cairo1.0 Contract:

Cairo0 Contract(for madara/sharingan):

HTLC Contract:

Nethermind Warp: docker run --rm -v ${PWD}/contracts/flatten:/dapp nethermind/warp transpile KamuiFlatten.sol