Timing

Sova makes one block per Zcash block: about a minute on average, and a five-minute gap is normal. Zcash testnet also has bursts of blocks a few seconds apart. Design for few, full transactions.

Four habits

• Batch. Put many calls in one transaction: Multicall3 at 0xa7c966ccffA9681a9662ceA416Ca3c360dC42ac0 on the testnet, or an EIP-7702 batch from your own account (Prague rules apply).
• Pipeline. Send a run of transactions with consecutive nonces at once. Don’t wait for each receipt before sending the next.
• Wait. eth_sendRawTransactionSync returns the receipt. A node waits up to 300 s (SOVA_SEND_SYNC_TIMEOUT_SECS); the public RPC waits up to 90 s. After a timeout, poll eth_getTransactionReceipt: the transaction is still in the pool.
• Count Zcash blocks. Use anchor()’s height, or block.timestamp (the Zcash block’s time). Not block.number: Sova’s block rate may change, Zcash’s height won’t. ZecCheckout counts its payment window in Zcash blocks.

Settlement

Sova settles on Zcash. Mints are final at Zcash depth, and a transaction is settled once three more epochs are built on it (about four minutes). ZEC payments wait for their own confirmations: 3 on testnet, 10 on mainnet.

On the testnet, the RPC’s safe (3 blocks) and finalized (100 blocks) labels are conveniences for tools, not guarantees: what this testnet is.

Mapping heights

Sova block N anchors Zcash height N + B − 1, where B is the network’s epoch base. On the testnet B is 4388500, so a burn in Zcash block h is paid in Sova block h − 4388500 + 1. Contracts read the anchor with anchor().