ProofStack solves the most urgent problem in media today: proving you created something first, before AI can replicate or backdate it. One API call registers a cryptographic fingerprint of your content on a tamper-evident Merkle chain. No blockchain required, no wallet needed.
Key Features
- >SHA-256 Content Hashing: Content is never stored — only its cryptographic fingerprint
- >Merkle MMR Audit Chain: Every proof is chained using a Merkle Mountain Range, making tampering cryptographically detectable
- >Tamper-Evident Receipts: Each receipt contains leaf_hash, mmr_root, and timestamp — independently verifiable by any party
- >Content Lookup by Hash: Retrieve any proof by content hash without knowing the proof ID
- >Chain Integrity Verification: Recompute the leaf_hash from prev_root and confirm it matches
- >4-Endpoint REST API: Register, retrieve, lookup, and verify — no SDK needed
- >No Crypto Wallet: Works from any HTTP client, any language
How It Works
- 1.1. `POST /v1/proof` with your content or its SHA-256 hash`POST /v1/proof` with your content or its SHA-256 hash
- 2.2. Receive a receipt: proof_id, content_hash, leaf_hash, mmr_root, timestampReceive a receipt: proof_id, content_hash, leaf_hash, mmr_root, timestamp
- 3.3. Later, `POST /v1/proof/{id}/verify` with the original content to prove it existed unchangedLater, `POST /v1/proof/{id}/verify` with the original content to prove it existed unchanged
- 4.4. The chain integrity check recomputes the Merkle path — any tampering is immediately visibleThe chain integrity check recomputes the Merkle path — any tampering is immediately visible
Use Cases
- >Journalists: Prove a story was drafted before a competing publication
- >Photographers: Timestamp images before AI tools can generate lookalikes
- >Developers: Register code before filing a patent or open-sourcing
- >Publishers: Fight AI content fraud with cryptographic evidence of creation date
Revival Story
Poet (Po.et, YC W17) raised $11M to do exactly this on Ethereum. It died under gas fees and blockchain overhead. ProofStack does the same thing with a simple REST API — no gas, no wallets, sub-100ms receipts.
Tech Stack
FastAPI, Python, SQLAlchemy, PostgreSQL (Merkle chain persistence), SHA-256 cryptography. Deployed as part of the AIOS kernel.