Introduction to Kist
Kist is a free proof-capture network. Photos and documents captured in the Kist Capture App are cryptographically signed on device, hashed, and permanently anchored on Solana — where anyone can verify them without trusting Kist.
Free Capture App
Anyone can capture and anchor signed proofs at no cost.
Developer API
Anchor and verify proofs from your own backend, postpaid.
Trust-minimized
Verification reads Solana directly — no Kist trust required.
What Kist is
Kist turns a captured image or document into a tamper-evident record. The device signs the content hash with an Ed25519 key, the Kist relayer verifies that signature, and the proof is written to an Anchor program on Solana. From then on, the original content can be proven to have existed, unmodified, at a specific time — by anyone.
The Capture App and every proof it anchors are free. Only programmatic API usage from your own backend is metered, and it is billed postpaid.
The pieces
- Capture App — a Flutter app (Android/iOS) that captures, signs, and stores proofs offline-first in a local SQLite ledger.
- Relayer API — verifies signatures, meters credits, and submits anchor transactions to Solana.
- Solana program — the on-chain source of truth: devices, proofs, and ownership live here.
- CLI & SDK — developer tooling to anchor and verify proofs from scripts, servers, and CI.
- Console — your dashboard for API keys, usage, and credit billing.
Why a blockchain
A normal database is owned by whoever runs it. Kist's proofs live on a public ledger, so verification does not depend on Kist being online, honest, or even in existence. The record survives on the strength of the chain.
Proofs settle in sub-second time on Solana devnet today, with the same flow targeting mainnet.
Where to go next
- Follow the [quickstart](/docs/quickstart) to anchor your first proof.
- Understand the trust model in [how proofs work](/docs/concepts).
- Read the full [API reference](/docs/api-reference).