OctoIntents

Demo

About

### 🔍 Project Description **Unifying EVM & BTC using Cross-Chain Intents and Dutch Auctions** This project introduces a trust-minimized cross-chain interoperability framework that unifies the Bitcoin and Ethereum ecosystems through **cross-chain intents**, **Hyperlane messaging**, **ERC-7683**, and a **Dutch auction-based solver mechanism**. It enables users to seamlessly bridge tokens between heterogeneous chains (such as Ethereum Sepolia, Rootstock, and Citrea testnets), while optimizing for **capital efficiency, decentralization, and settlement speed**. At its core, users express *what* they want done (not *how*) by submitting **intents**, which solvers then compete to fulfill via **on-chain Dutch auctions-based selection mechanism**. --- ### 🔁 How It Works – End-to-End Flow 1. **User Opens Intent (Deposits Tokens to Escrow on Chain C1)** A user (e.g., Alice) deposits tokens into an **escrow contract** on **Chain C1** (e.g., Ethereum Sepolia). This deposit triggers the creation of a formal **intent**, which describes Alice’s desired action—typically, to receive the equivalent value of tokens on **Chain C2**. 2. **Intent Message Dispatched via Hyperlane** The intent metadata is securely dispatched from Chain C1 to Chain C2 using **Hyperlane Mailbox**, a modular interchain messaging protocol that ensures trustless communication. 3. **Dutch Auction Starts on Chain C2** Upon receipt, Chain C2 initiates a **Dutch auction** representing the open intent. The auction begins with a high reward (price) and linearly **decreases over time** until a solver accepts the task. 4. **Solver Selection via Dutch Auction** Multiple solvers monitor Chain C2 for open intents. The first solver to accept the current price **wins the auction**, locking in their right to fulfill the intent. 5. **Solver Executes and Fills Intent** The winning solver **delivers the required tokens to Alice on Chain C2**, effectively fulfilling the user’s request. 6. **Escrow Settlement on Chain C1** Once fulfillment is verified (using Hyperlane messages), the solver can **claim Alice’s originally escrowed tokens** from Chain C1—completing the **settlement process**. --- ### 🧠 Why This Matters This approach solves key limitations of traditional bridging and settlement mechanisms: #### ❌ The Problem: Slow and Centralized Settlements - **Hours of Waiting** – Solvers often wait hours to receive funds post-settlement. - **Limited Access** – Only a few privileged actors can act as relayers/solvers. - **Centralized Control** – Trust assumptions remain high, and systems lack transparency. --- ### ✅ The Solution: Intents + Dutch Auctions + Hyperlane - **Trustless Fulfillment** – Settlement is enforced via escrow and cross-chain proofs. - **Decentralized Solver Market** – Anyone can compete to fulfill intents using open auctions. - **Faster Execution** – Settlement is near-instant post-fulfillment verification. --- ### 📊 Capital Efficiency: Why Dutch Auctions Matter Traditional bridges suffer from inefficiencies due to long settlement cycles and liquidity lock-up. This system radically improves **capital efficiency**, making bridging more sustainable and accessible. According to **DeFiLlama (Feb 12, 2025)**, Across facilitated ~$19.1M in volume and ~9500 bridge transactions in 24h across Ethereum, Optimism, and Arbitrum. This translates to: - 1 transaction every **20 seconds on Ethereum** - 1 transaction every **40 seconds on rollups** Now consider capital locked up for solvers: - If paid **every 60 minutes**, a solver must maintain **$800K in inventory** across 3 chains. - If paid **every 1 minute**, they only need **~$13,500**. This is a **60x improvement in capital efficiency**. By enabling faster solver settlement through Dutch auction-based intents and instant on-chain verification, the system **reduces the opportunity cost**, thereby lowering user fees and increasing solver participation. --- ### 🌐 Deployed Networks - **Ethereum Sepolia Testnet** - **Rootstock Testnet** - **Citrea Testnet** --- ### 🧩 Built With: - **ERC-7683** – Standard for cross-chain intents - **Hyperlane** – Interchain messaging layer - **Dutch Auction Contracts** – For solver selection and pricing - **Escrow Mechanism** – For atomic intent lifecycle across chains --- This project brings us closer to a **modular, unified cross-chain future**, bridging the liquidity, programmability, and users of Bitcoin and Ethereum ecosystems through **intent-based interoperability**—efficient, decentralized, and scalable.

How it's made

This project is a modular cross-chain settlement framework that unifies EVM and Bitcoin ecosystems using **ERC-7683 intents**, **Hyperlane-powered messaging**, and a **Dutch auction-based solver selection mechanism**. It enables capital-efficient, permissionless, and transparent bridging between chains like **Ethereum Sepolia**, **Rootstock**, and **Citrea**. --- ### 🧱 Core Architecture #### 1. **Intent Creation & Escrow (Chain C1)** The bridging process begins when a user deposits tokens into an **ERC-7683-compliant escrow contract** on Chain C1. This deposit acts as a **cross-chain intent**, encoding: - Source and destination chains - Token type and amount - Minimum acceptable output - Auction and settlement configuration The escrow holds user funds while awaiting settlement. #### 2. **Cross-Chain Intent Dispatch with Hyperlane Mailbox** The intent message is dispatched to Chain C2 using the **Hyperlane Mailbox** and **Hyperlane Messenger**, forming a part of the **Open Intents Framework (OIF)**. This enables **secure and programmable message passing** between heterogeneous chains. Upon receipt, the destination chain contract parses the message and launches a solver auction. #### 3. **Custom Dutch Auction-Based Solver Selection (Chain C2)** Once an intent is received, our system initiates a **custom Dutch auction** to select the solver. Unlike static pricing or round-robin relayers, our approach dynamically discovers the best price through open competition: - Auctions begin at a high reward for solvers - The price **decreases linearly over time** - The **first solver to accept the current price** wins the auction - The auction ends if no solver accepts within the defined time window This mechanism ensures **capital-efficient, decentralized, and transparent solver selection**, preventing centralization and maximizing value returned to the user. #### 4. **Solver Settlement & Fulfillment** The winning solver: - Transfers the output tokens to the user on Chain C2 - Fulfills the intent by submitting proof (or interaction) back to the escrow contract on Chain C1 The escrow verifies the fulfillment and **releases the user’s tokens** to the solver, finalizing the swap. --- ### 🛠️ Technologies & Tooling Used | Tech/Tool | Purpose | |------------------------|-------------------------------------------------| | **Solidity** | Smart contracts for intents, auctions, and escrow | | **ERC-7683** | Standard for intents and settlement interfaces | | **Hyperlane** | Cross-chain messaging (Messenger + Mailbox) | | **Open Intents Framework (OIF)** | Intent modeling and routing | | **Rootstock & Citrea** | EVM-compatible Bitcoin networks for BTC bridging | | **Foundry** | Development, scripting, and testing | | **Ethers.js** | JS SDK for on-chain interactions and frontend integration | --- ### 🤝 Partner Integrations - **Hyperlane** enabled cross-chain messaging through its **Mailbox** contracts and **Messenger pattern**. We integrated Hyperlane into our intent settlement logic. - **Citrea** offered a ZK-rollup on Bitcoin, which allowed us to explore native BTC-EVM bridging with intents. - **Rootstock** brought smart contract programmability to Bitcoin’s security layer, enabling native escrow and solver flows on BTC-linked networks. --- ### ⚙️ Hacky/Notable Engineering Wins - **Unique Dutch Auction-Based Solver Selection**: Our custom-designed solver auction contract deploys auctions **per-intent**, where price decays over time until accepted by a solver. This reduces solver hoarding and introduces fair, dynamic participation. It brings **price discovery into the settlement process itself**, unlike most bridging protocols that preselect relayers or quote fixed prices. - **Deployed Hyperlane on Rootstock Testnet**: Since Hyperlane wasn't already present on Rootstock Testnet, we **manually deployed the full suite of Hyperlane core contracts** to bootstrap message routing between Sepolia and Rootstock. - **Manual Message Relaying to Trigger Dutch Auctions**: We used the **Hyperlane CLI** to manually relay messages from Sepolia to Rootstock in the absence of an automated relayer. This confirmed that intent dispatch and auction triggering could work **end-to-end even in low-infra testnet environments**. --- ### 📈 Capital Efficiency Advantage According to a capital analysis inspired by DeFiLlama's stats from Feb 12, 2025: - Across processed ~$19.1M in daily bridging volume with 9507 transactions - Assuming one TX every 20–40 seconds, a solver would need ~$800K inventory **if paid hourly** - With our **minute-level settlement capability**, a solver only needs ~$13.5K inventory across chains 👉 This results in a **60x improvement in capital efficiency** By reducing the capital lockup for solvers, we drastically reduce costs and **fees for users**, while expanding **decentralized access to solver roles**. --- ### 🧩 Solving the Status Quo | Problem | Our Solution | |------------------------|--------------------------------------------------| | **Slow Settlements** | Real-time solver auctions + fast fulfillment | | **Centralized Solvers**| Open auction-based selection mechanism | | **Capital Intensive** | High-frequency payouts → low inventory needs | | **Opaque Systems** | Transparent, on-chain auction & intent lifecycle | --- ### 🚀 Summary We’ve built a protocol that combines **ERC-7683 intents**, **Dutch auction-based solver selection**, and **Hyperlane messaging** into a trust-minimized framework for cross-chain settlement. It unlocks fast, transparent, and capital-efficient bridging across Ethereum, Rootstock, Citrea, and eventually Bitcoin.