Streams

Large files split across an ordinal transfer chain

Large payloads can be split across multiple inscriptions on one ordinal transfer chain, then reassembled by OrdFS.

On-chain layout

1. Chunk 0 (start of stream): the payload’s actual content type (e.g. video/mp4, application/octet-stream). Conventionally mark it as streamable, e.g. video/mp4; stream=ordfs (parameter on the type string). Body is the first slice of bytes.

2. Further chunks: each successive spend of the ordinal carries the next slice with content type exactly ordfs/stream.

3. Chain ends when a spend has no further content, spend is missing, or a later output’s type is not ordfs/stream (after the first chunk).

All chunks must be in the instance’s BEEF/spends graph so the stream walk can follow the ordinal. Same scope rules as other OrdFS loads.

Serving

GET /1sat/ordfs/stream/{outpoint}

OrdFS:

1. Resolves origin / chain from the starting outpoint.

2. Walks spends forward, concatenating content bodies in order.

3. Sets Content-Type from the first chunk’s type (so clients see video/mp4, not ordfs/stream).

4. Supports HTTP Range (Range: bytes=start-end) for seek and progressive download; only the relevant portions of chunks are written.

Example:

curl -H "Range: bytes=0-1023" "https://{host}/1sat/ordfs/stream/{txid}_{vout}"

GET /content/{outpoint} on a stream origin returns only that outpoint’s inscription (typically chunk 0), not the assembled stream. Use the stream route for full media.

Deploying a stream

1. Split the file into chunks sized for your inscription limits (1 MiB bodies are a practical default).

2. Mint chunk 0 as a 1-sat inscription with the public content type (and optional stream=ordfs parameter).

3. Transfer/reinscribe the same ordinal for each subsequent chunk with type ordfs/stream and the next bytes (order is spend order).

4. Point clients at /1sat/ordfs/stream/{firstChunkOutpoint} (or an outpoint mid-chain if you only need a suffix — walk starts from the requested outpoint).

If a middle chunk is missing from the store, the stream stops or errors when that spend cannot be loaded.

Reference mint (@1sat/actions)

The TypeScript SDK’s inscribe action can build this layout:

• stream: true — multi-tx stream with 1 MiB chunk bodies

• streamChunkSize: N — multi-tx stream with custom body size

Omit both for a single-transaction inscription. Stream outputs are tagged with sha256:<content-hash> and stream-i:<index>. See Libraries and 1sat-sdk.

See also

• OrdFS — gateway resolution, seq, MAP, HTTP routes

• Directories — multi-file sites via ord-fs/json