Inch Care

InchCare is a cross-chain medical finance and incident reporting platform built for real-world utility in healthcare, powered by 1inch Fusion SDK+. It enables patients, NGOs, and healthcare providers to report medical incidents on-chain, and facilitates cross-chain insurance payouts across ecosystems like Filecoin, Starknet, Stellar & Optimism, Arbitrum and Ethereum.

At its core, InchCare uses 1inch Fusion’s intent-based architecture to coordinate trustless swaps and settlements between chains. We’ve developed an Patient Pro (PPT) utility token on Starknet and Filecoin, which is used for token-gated access to health services, claim submission, and invoicing workflows. Using Fusion SDK+, we enable decentralized insurance payouts through secure swaps between Ethereum, Starknet, and Filecoin, using custom escrow contracts with hashlock and timelock logic.

On Stellar, we log medical incident metadata immutably using Soroban smart contracts. On Filecoin, encrypted medical records (invoices, reports) are stored with IPFS, and linked to on-chain claim references. To further secure the system, we’ve built a rate limiting protocol on Ethereum Sepolia to throttle claim attempts and ensure system integrity.

InchCare showcases how DeFi primitives like 1inch Fusion+ can be extended to serve real-world impact verticals like healthcare, delivering tokenized, multi-chain access and insurance settlement tools for underserved populations and decentralized health networks.

We built InchCare as a modular cross-chain protocol combining DeFi tooling, healthcare access control, and decentralized insurance settlement — stitched together using the 1inch Fusion SDK+ as the connective tissue between ecosystems.

Our project is centered around a custom Patient Pro (PPT) utility token deployed on both Starknet (using Cairo v1) and Filecoin EVM, which enables token-gated access to features like submitting medical invoices or viewing encrypted reports. We wrote custom smart contracts to validate ownership and permissions, integrating with frontends built using ICP's canister-based architecture.

To enable cross-chain insurance claim fulfillment, we used 1inch Fusion SDK+ to perform intent-based swaps between Ethereum, Starknet, and Filecoin. We designed a system of custom escrow contracts (EscrowSrc and EscrowDst) with hashlock and timelock logic, enabling conditional release of funds between chains when an incident is verified and the secret is revealed. We worked around cross-chain communication limitations by carefully structuring preimage commitments and syncing them via off-chain watchers.

Medical incidents are logged on Stellar using a Soroban smart contract that writes event metadata (with hashed identifiers for privacy) immutably on-chain. Associated documents (like medical invoices and patient reports) are encrypted and stored on Filecoin using IPFS — and the content hashes are linked from the on-chain incident records. We also deployed a rate-limiting protocol on Ethereum Sepolia to prevent abuse of claim submission by enforcing a cooldown period between actions. This was especially useful in our testing to simulate real-world APIs that require regulated access.

On the hacky side, we extended the 1inch Fusion SDK+ to work with both Starknet and Filecoin by manually crafting calldata for non-EVM environments and adapting escrow resolution flows. Getting Fusion+ to trigger across rollup and L1 environments while preserving atomicity required some workarounds involving off-chain monitoring scripts and automated relayers.

By combining these systems, we’ve created a real-world use case where DeFi meets healthtech — and where smart contracts, tokens, and cross-chain protocols come together to support global medical infrastructure.