Module ots_anchor 

Bitcoin OTS anchor loop.

Periodically submits the current tree head to multiple OpenTimestamps calendar servers. The OTS proofs are stored in the database and served via GET /v1/head/<N>/ots.

Frequency

Every 10 minutes by default. OTS aggregation means the per-batch Bitcoin cost is amortized across many log submitters; the actual on-chain footprint is one OP_RETURN per calendar per hour.

Calendar servers

The default set mirrors what opentimestamps-client ships:

• https://a.pool.opentimestamps.org
• https://b.pool.opentimestamps.org
• https://a.eternity.college
• https://ots.btc.cat

A calendar failure is non-fatal — the anchor proceeds with whichever calendars respond.

Functions

anchor_once 🔒

One anchor cycle: snapshot the current tree head, submit to OTS calendars, store the result. Returns Ok if at least one calendar accepted.

build_placeholder_proof 🔒

Build a placeholder OTS proof for testing. The real implementation would parse the calendar server responses and assemble the proof per the OTS wire format (RFC opentimestamps).

run_anchor_loop

Run the OTS anchor loop in the background. Submits the current tree root to calendar servers at the configured interval.