Pixa
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Permanence and Provenance

Status: Live

Checked against the chain and the app at commit ca1d157 on 2026-10-05.

Two promises are often made for art on a blockchain: that it lasts, and that it proves who made it. This page says exactly how far the Pixa chain keeps each promise, and where it stops. It also describes the licence every artwork carries.

Permanence

How long an artwork lasts. An artwork sits in a block, and blocks are copied by every node that keeps the chain's full history. The artwork lasts as long as someone keeps that history. No company has to stay in business and no image host has to keep a file. The record of the first Steem blocks of 2016 is still served today by nodes of the chains descended from it (From STEEM to HIVE to PIXA). Permanence on a chain is a matter of continued operation, not a guarantee. It is still a far stronger basis than a link.

What irreversible means. Within a few seconds a block becomes irreversible: enough witnesses have confirmed it that it will never be replaced (Chain Parameters). From then on, its contents never change.

Edits and deletions leave past blocks unchanged.

You do The chain records What remains
Edit an artwork A new comment operation with the same permlink Every earlier version, in its block
Delete an artwork in the app A new version whose body is deleted, marked as deleted in its metadata The original image, in the block where it was first published
Delete a post or reply with delete_comment A deletion, allowed only before payout, and only with no replies and no net positive votes. The post leaves the chain's current state and the API. The original, in the block where it was published

Consequences

  • Nothing can be withdrawn. Personal data, a mistake, or a work you later want withdrawn will stay readable to anyone who looks at the history.
  • Interfaces can hide; the record cannot change. An app can hide something, and it may be legally obliged to. The record stays as it is.

Provenance

When you publish, the chain records:

  • Who: the author's account, proven by a signature from its posting key.
  • When: the block's number and timestamp. Blocks come every 3 seconds, so this is precise to within 3 seconds.
  • What: the exact bytes of the image.
  • Which transaction: an id anyone can look up.

Checking it yourself. These calls show the post as it is now, list the author's posts with the block each was written in, and fetch that block:

Shellcurl -s -X POST https://api.pixagram.com -H 'Content-Type: application/json' \
  -d '{"jsonrpc":"2.0","method":"condenser_api.get_content","params":["AUTHOR","PERMLINK"],"id":1}'
curl -s -X POST https://api.pixagram.com -H 'Content-Type: application/json' \
  -d '{"jsonrpc":"2.0","method":"condenser_api.get_account_history","params":["AUTHOR",-1,1000,2,0],"id":1}'
curl -s -X POST https://api.pixagram.com -H 'Content-Type: application/json' \
  -d '{"jsonrpc":"2.0","method":"condenser_api.get_block","params":[BLOCK_NUMBER],"id":1}'

What provenance proves:

  • This account published these bytes at this time.
  • No earlier post on this chain has the same bytes, if you search for them.

What provenance does not prove:

  • That the publisher made the work. Anyone can publish a copy of someone else's image. The chain proves who posted first on this chain, not who created the work.
  • That the work is original. The app does not check for copies yet. The project has published a perceptual-hash library for detecting near-identical pixel art, but nothing uses it so far.
  • Anything about other chains or the wider web. An image posted earlier elsewhere has its own history there.

Licence

Every artwork the app publishes carries a licence record in its metadata: the PIXA NFT LICENSE 1.0. The author can switch each right on or off. These are the defaults:

Rights of the holder

Right Default
Display for personal, non-commercial use on
Commercial use on
Social media or advertising on (needs commercial use)
Printing on physical goods on (needs commercial use)
Licensing to third parties, such as stock sites off (needs commercial use)
Modifying or adapting on
Public derivative works or remixes on (needs modifying)
Minting the work or derivatives as new NFTs off (needs modifying)
Use in virtual worlds, games, apps, music videos, films, exhibitions and education on

Rights of visitors

Right Default
Share with credit to the author on
Share without credit off
Modify and share under the same licence off
Train or use in AI or machine-learning models on

The record also holds:

  • A royalty percentage, 5% by default.
  • Governing-law fields: a jurisdiction, a court and arbitration terms.

Who enforces the licence. The licence is a statement of the author's terms, recorded publicly with the work. The chain does not enforce it. In particular, no royalty is collected anywhere today, because there is no marketplace yet (NFTs and Marketplace). Enforcing it is a matter for the law of the jurisdiction the author names. The governing-law fields are empty by default, and most artworks published so far leave them empty.

Inherited → changed

Aspect Steem / Hive Pixa
What the chain records for an image Usually a link The image itself
Proof of who posted first Yes, for the post's text Yes, for the post and the artwork's bytes
Licence record None by default PIXA NFT LICENSE 1.0 in every artwork's metadata
Originality checks None None yet

Sources