palimpsest-replay

Deterministic reconstruction from stored artifacts. Same envelope + same storage = bit-identical output.

Concept

The replay engine retrieves the ExecutionEnvelope and stored blobs for a given URL and timestamp, then reconstructs:

1. HTTP exchange — request and response headers + body
2. DOM state — rendered DOM from the dom-snapshot record
3. Resource graph — sub-resource dependency tree with load ordering

Usage

#![allow(unused)]
fn main() {
let entries = index.history(&url);
let latest = entries.last().unwrap();
let blob = store.get(&latest.content_hash).await?;
}

For full reconstruction including DOM and sub-resources, the replay engine reads the complete CaptureGroup from the WARC++ file and rehydrates each record.

Law 5 Guarantee

Replay fidelity is the proof that the archive works. If the same envelope and the same artifacts produce different output on two runs, Law 5 is violated.

The simulation framework verifies this: verify_determinism crawls twice with the same seed and asserts byte-identical blob hashes, index entries, and page counts.

Related Crates

• palimpsest-storage — provides blob retrieval
• palimpsest-index — provides temporal lookups
• palimpsest-artifact — provides WARC++ record parsing
• palimpsest-envelope — provides execution context