Anchors (DGCH)

An anchor writes a fingerprint of the side-chain into the Divi testnet, so the history cannot be quietly rewritten later.

Every every blocks ([anchor] every, default 300, about 10 minutes when busy) the sequencer broadcasts an OP_RETURN transaction:

"DGCH" || 0x01 || height u64 LE || block_hash[32] || state_root[32]      (77 bytes)

• It is paid from the sequencer's own Divi testnet address.
• The Divi txid is written back to the side-chain as a system/anchor_recorded action, so anyone can find the anchor from either side.
• Anchoring is off until the sequencer address has testnet DIVI ([anchor] enabled = true).

What an anchor proves

If the operator later shows you a different history, its state_root at the anchored height will not match what Divi already holds. The Divi chain's ordering of that transaction also bounds when the anchor existed.

What it does not prove

It does not make the sequencer honest between anchors, and it does not move funds. It is evidence, not enforcement. The 77 bytes are small enough to fit comfortably in an OP_RETURN.