Blockchain + AES-256 + IPFS + React.js Healthcare Data App or website

Project overview
I need a full, ready-to-deploy web application that implements my academic project:
“Leveraging Blockchain and AES for Trusted and Confidential Healthcare Information Exchange.”

The system must ensure files are encrypted client-side with AES-256, stored on IPFS, and the resulting CID is registered on a blockchain for tamper-proof verification. A Solidity smart contract must store and manage metadata/access where applicable.

Core features / requirements
1. AES-256 encryption module:
• In-browser AES-256 encryption/decryption (so raw files are never uploaded unencrypted).
• Acceptable libraries: Web Crypto API, crypto-js, or equivalent vetted implementation.

2. Blockchain (Ethereum) & Smart Contract:
• Solidity smart contract implementing:
- uploadRecord(recordId, ipfsCid, metadata)
- grantAccess(recordId, userAddress)
- revokeAccess(recordId, userAddress)
- verifyAccess(recordId, userAddress) -> bool
• Deploy to a local testnet (Ganache) for demo; testnet (Ropsten/Goerli) acceptable.
• Frontend/backend must show the on-chain Tx hash after storing CID.

3. IPFS Storage:
• Upload encrypted files to IPFS and return CID.
• IPFS gateway usage allowed (e.g., Infura) or local IPFS node for the demo.

4. Frontend (React.js):
• React 18+ (TypeScript preferred but JS acceptable).
• Patient and doctor accounts (email/password).
• Patient dashboard: upload file (client-side encryption) -> upload to IPFS -> call smart contract -> show CID & Tx hash.
• Doctor flow: request/view files based on granted access.
• Users can download and decrypt their own files (password-derived key).

5. Backend (Node.js or Python Flask):
• Secure REST API for authentication (or Firebase/Supabase if used — must be documented).
• Handle server-side interactions with smart contract (if needed).
• Provide endpoints for retrieving user file lists, IPFS retrieval, and audit logs.

Deliverables
• Complete source code in a public/private GitHub repo.
• README with setup, environment variables, and deployment steps.
• Demo video (screen capture showing full flow: register, upload, store CID on chain, retrieve & decrypt).
• Short documentation of architecture and where to change config (IPFS, node RPC, keys).
• Smart contract code + migrations + ABI.

Acceptance criteria
1. Accounts can create/login/logout with email/password.
2. Any uploaded file (<100 MB) is encrypted in-browser, uploaded to IPFS, and returns a resolvable CID.
3. CID is written to blockchain in a confirmed transaction; UI shows Tx hash.
4. Patients can download & decrypt their files by providing their password.
5. Smart contract supports uploadRecord, grantAccess, revokeAccess, verifyAccess.
6. README and demo video exist and project runs locally following instructions.

Additional notes
• Security: use vetted crypto libraries; do not invent custom crypto. Salt/derive keys properly (PBKDF2 / scrypt / HKDF) if deriving keys from passwords.
• Use Ganache/Hardhat for local testing; show example deployment to an Ethereum testnet if feasible.
• Code should be modular, commented, and structured for review.

Please apply only if you have prior experience with:
• Solidity + Ethereum + Web3 (or ethers.js)
• React.js (hooks) and in-browser crypto
• IPFS integration
• Node.js or Python backend

Thanks.
Budget: ₹2,000 – ₹5,000 (fixed)
Timeline: 10–15 days

Suggested milestones:
1) Milestone 1 (30%): Smart contract + IPFS demo (upload CID & show Tx) on Ganache.
2) Milestone 2 (40%): AES encryption + IPFS upload + backend APIs + integrate with smart contract; basic React flows (upload, show CID/Tx).
3) Milestone 3 (30%): Full UI polish, download/decrypt flow, README, demo video and final delivery.

Payment only released per milestone after verification of deliverables.