UTXO protocols need off-chain executors

A lot of people approach UTXO smart contracts as if the contract is the whole application. In practice, the contract is only the rule system. Something still has to find boxes, assemble transactions, handle race conditions, retry failures, and keep the protocol moving.That is why many of my Cardano and Ergo projects include off-chain executors. Palm Economy needed executors for staking and emissions. Phoenix needed off-chain transaction logic so users were not relying on fragile frontend API calls. ZenGate's traceability work needed indexers, proof storage, and transaction-building infrastructure around the on-chain commitments.