9 min read
Yes. Label 309 is an open Proof of Existence standard: the code is Apache-2.0, the spec is CC-BY-4.0, and anyone can implement it, fork it, run a gateway, and build products without asking CardanoWall for permission.
The StandardDevelopers
9 min read
A Label 309 gateway is the publishing service that quotes, uploads, submits, confirms, and indexes Proof of Existence records through a standard API — while your keys stay on your device and proofs verify from public data.
DevelopersThe Standard
10 min read
The website is one interface, not the whole product. You can publish and verify Label 309 records through a CLI, SDKs, a gateway API, a desktop app, or your own service.
DevelopersGuides
9 min read
Publishing a CardanoWall proof costs money because the gateway pays real Cardano transaction fees and, for files, real Arweave storage — then adds a service margin to run a hosted service. Verifying stays free and needs no server.
GuidesDevelopers
9 min read
Yes — a company or developer can run their own Label 309 gateway, fund its Cardano and storage wallets, and publish standard proofs of existence without using CardanoWall as the hosted operator. Here is what that takes.
Developers
9 min read
A Merkle root lets one Label 309 record commit to thousands or millions of file hashes, then prove any single item later with a small inclusion proof — without putting every item on chain.
The StandardDevelopers
8 min read
A CI/CD pipeline can hash its build artifacts, SBOMs, logs, and release manifests, batch them into one Merkle root, and publish a single Label 309 proof — an independent public time anchor for later audits.
Developers
9 min read
Hash each AI output, prompt, manifest, or Content Credentials record, batch the hashes into Merkle roots, and publish timestamped Label 309 commitments — proving any single item existed without putting every asset or private prompt on chain.
AI & ProvenanceDevelopers
10 min read
Anchor a Merkle root of your compliance evidence on Cardano, and an auditor can later confirm a specific report or log was committed by a public time — without trusting the system that produced it.
Compliance & LegalDevelopers
7 min read
A Merkle root anchored with a Label 309 timestamp lets you commit to a snapshot of reserves, liabilities, or evidence and prove inclusion to individual customers — without publishing every account.
Compliance & LegalDevelopers
8 min read
Hash a dataset manifest, batch it with a Merkle root, and anchor it on Cardano with Label 309 — so you can later prove what a dataset snapshot contained without publishing the dataset.
AI & ProvenanceDevelopers
9 min read
Verify a Label 309 proof from the public Cardano chain, the record bytes, and optional content or recipient keys — without trusting CardanoWall or whoever published it.
DevelopersGuides
9 min read
Your first Label 309 proof can be a hash-only record: hash a file, get a price quote from a gateway, publish the digest on Cardano, and keep the transaction hash. Here is the full workflow.
GuidesDevelopers
10 min read
How to build your own product on CardanoWall: quote, upload, publish, read, verify, and monitor Label 309 records through the same gateway API CardanoWall itself runs on.
Developers
7 min read
Run Proof of Existence from a script: the cardanowall CLI puts JSON on stdout, diagnostics on stderr, gives you stable verification exit codes, takes secrets safely, and publishes through any Label 309 gateway.
Developers
10 min read
A Label 309 gateway is the publishing engine behind a Proof-of-Existence product: it owns Cardano submission, storage, balances, indexing, and webhooks, so your product can own the user experience instead.
Developers
7 min read
Sigstore signs software artifacts and logs the event publicly; Label 309 adds an independent blockchain time anchor over your whole release evidence. They solve different problems and work well together.
The StandardDevelopers