Build cross-chain bridge with HTLC atomic swap for Stellar-EVM transfers

[Smartdevs17]

Context

AgenticPay supports both Stellar and EVM chains but lacks a production-ready cross-chain bridge. An HTLC-based atomic swap would enable trustless cross-chain payments.

Current Limitation

Users cannot move assets between Stellar and EVM chains within the platform.

Expected Outcome

• HTLC contract on both chains for atomic swaps
• Relayer service for monitoring and coordinating swaps
• Configurable timelock periods and hash algorithms
• Support for XLM, USDC, and custom tokens

Acceptance Criteria

• HTLC contracts deployed on both Stellar and EVM
• Relayer service monitors HTLC events on both chains
• Atomic swap initiation, claiming, and refund flows
• Timeout-based refund mechanism with safety margins
• Support for multiple token types (native + ERC20/Soroban tokens)
• E2E tests for complete cross-chain swap lifecycle

Technical Scope

• contracts/evm/contracts/BridgeHTLC.sol - EVM HTLC contract
• contracts/bridges/ - Bridge contract implementations
• backend/src/services/bridge.ts - Bridge coordination service
• frontend/app/dashboard/bridge/ - Bridge UI components

[divysam]

@divysam has applied to work on this issue as part of the Stellar Wave Program's 7th wave.

Hello
I would love to work on this issue please

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[dimka90]

@dimka90 has applied to work on this issue as part of the Stellar Wave Program's 7th wave.

Can i work on this?

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[Caneryy]

@Caneryy has applied to work on this issue as part of the Stellar Wave Program's 7th wave.

Hi there, can I work on this issue?

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Congratulations, @dimka90! 🎉 Your application was accepted by the repo's maintainers, and the issue is due on July 30, 2026.

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[drips-wave]

This issue has been completed by @dimka90 as part of the Stellar Wave Program's 7th Wave 🥳

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