Purpose. Continuation of the FAQ with domain-oriented and operational questions, hybrid patterns, and edge cases. All math is plain ASCII (inline code).
Q13. Which kinds of real-world workflows benefit most?
Anything that needs offline, tamper-evident provenance: field research notebooks, remote journalism, lab datasets, creative drafts, supply-chain handoffs, edu/exams, legal discovery packs, insurance claims bundles, IoT/edge logs, and archival snapshots. Stamp locally now; publish a daily anchor later.
Q14. Can I embed the stamp line inside the file instead of a sidecar?
Yes, in addition to the sidecar. Embed the exact ASCII line in a safe metadata field (e.g., PDF comment, image UserComment). Verification still uses the sidecar (canonical). The embedded copy is convenience only.
Q15. What if my platform writes CRLF vs LF?
That changes the file digest by design. Both are valid if stamped as-is. The stamp captures the exact bytes present. Anchors and chains are unaffected because they operate on stamp lines, not raw files.
Q16. How do I merge stamps from multiple devices without collisions?
Use optional provenance keys in the kv: tail: kv:chain_id=<8hex>;device=<token>. Chains remain per-ledger (append-only). Merging ledgers is a file/process concern; stamps themselves don’t collide because chain_k = H_chain( ascii(chain_{k-1} + "|" + stamp_core) ) ties each link to its history.
Q17. What if a ledger gets corrupted or rows are deleted?
Rebuild from sidecars: start at chain_0 = "0"*64, recompute each chain_k from each file’s stamp_core, and rewrite a fresh ledger. A rewalk detects the first index where any legacy ledger diverged.
Q18. How often should I publish anchors? What does it buy me?
Anchors turn local integrity/order into a public “no-later-than” claim. If you publish daily, your backdating window is bounded:max_backdating_window_sec <= anchor_period_sec.
High-value streams can anchor hourly; low-value streams can anchor daily.
Q19. Can I add authorship or organization identity later?
Yes—sign the exact ASCII line without changing it:sig = Ed25519_sign(priv, ascii(SSMCLOCK1|...|chain[|kv:...]]))
Publish the signature alongside the stamp (or in the daily note). Verification of stamp and signature are independent.
Q20. How do I interoperate with traditional timestamping?
Hybrid is straightforward: keep the core stamp; when publishing the daily note, also obtain a TSA token for the same rollup_D or post rollup_D on-chain. The stamp remains unchanged; third-party time/attester rides on the anchor.
Q21. Can I stamp very large files efficiently?
Yes. Compute h_file = H_algo(file_bytes) via streaming chunks; the digest must match the monolithic result. The stamp line is still one ASCII row.
Q22. What if the stamper’s local clock is wrong?
The stamp’s iso_utc is declarative; the deterministic clock derives from it:wrap360(x) = x - 360*floor(x/360)theta_deg = wrap360( (unix_seconds / 86400) * 360 )rasi_idx = floor(theta_deg / 30)
To reduce drift risk, either publish anchors promptly or use optional observed-time evidence in a sidecar; core verification remains unchanged.
Q23. Does stamping reveal anything sensitive about contents?
Only the digest and the byte-accurate presence of the file (integrity), not the file itself. If the plaintext must remain secret, publish only anchors (daily rollup_D) and share stamps privately. Preimage safety follows your chosen H_algo.
Q24. How strict are the angle printing rules across languages?
Very. Always use IEEE-754 binary64 math and print with exactly theta_prec digits (default 5) using ties-to-even. Verifiers compare strings; a tight numeric tolerance is optional as a fallback.
Q25. Can I change algorithms mid-stream?
Yes, per-stamp agility via the kv: tail:kv:algo ∈ {sha256, sha3_256, blake2b-256}, kv:chain_algo ∈ {sha256, sha3_256, blake2b-256}.
Anchors always hash the ASCII-joined stamp lines with sha256 to keep roll-ups universal.
Q26. What happens if I try to stamp during a leap second?
Forbidden by policy. Reject any iso_utc with :60. Verifiers must fail such lines.
Q27. Can I verify without the original file?
You can only check chain/anchor consistency. File integrity (HASH_OK) needs bytes to recompute h' = H_algo(file_bytes). A missing original with a sidecar is an “orphan” and should be flagged for audit.
Q28. How big is the attack surface of the chain?
The chain is a one-way recurrence:chain_k = H_chain( ascii(chain_{k-1} + "|" + stamp_core) ) with chain_0 = "0"*64.
Any deletion or reorder breaks rewalk at the first inconsistency. Publishing daily anchors and (optionally) a witness_chain_tip detects forks after the fact.
Q29. How do I pick theta_prec?
Default theta_prec=5 balances human legibility with collision resistance on the printed angle. Allowed range is 3..9. All parties must emit/compare exactly the same number of digits.
Q30. Can I use this for bundled evidence (e.g., claim packages, discovery sets)?
Yes. Stamp each artifact as created, keep an append-only ledger, and publish a daily anchor for the bundle. Later, a reviewer can verify each file (HASH_OK), the local order (CHAIN_OK), and the day-level bound from the anchor (ANCHOR_OK), all offline.
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