Cantor · Aftermath Research

Liquidation bots on Sui can spend a few thousandths of a dollar on a transaction, or hundreds of dollars competing for the right to execute it. The code has not become thousands of times more expensive. The opportunity has.

That difference is worth examining because much of the value in a conventional DeFi liquidation is assigned before the liquidator does any work. A protocol announces a collateral discount. Whoever gets the transaction through first collects it. When the discount is large and the execution cost is small, bots have a reason to spend the difference on transaction priority.

Say you’re a lender with 100,000 USDC. You’re comfortable financing ETH-backed loans up to 65% LTV, and BTC-backed loans up to 60% LTV, on terms you’ve already worked out — acceptable oracles, acceptable liquidation rules, a minimum return you won’t go below. What you don’t know yet is whether tomorrow’s borrower will want to post ETH or BTC. Nobody does, until the borrower shows up.

Most isolated lending markets ask you to guess anyway. Before any borrower exists, you have to park your USDC in one market or the other — say, 70,000 in the ETH pool and 30,000 in the BTC pool. If a BTC-backed borrower later asks for 30,000 and only 20,000 sits in that pool, the remaining 10,000 is stuck on the wrong side of a wall you built for reasons that have nothing to do with your actual appetite for risk. You were willing to make the loan. The capital was sitting uncommitted. It just wasn’t in the right room.

The easy way, and where it breaks

Say you’re building an allowlist on Sui — a gated mint, an airdrop, a per-epoch settlement of payout claims. A Move module needs to answer one question, over and over, for the life of the contract: is this item in my set?

For a handful of entries, the answer is boring and correct. Put them in a vector<u64>. When the collection grows, reach for sui::table, which gives you keyed storage and table::contains for the membership check [1]. The data lives onchain, it’s authoritative, and the transaction reads it directly. If that’s your situation, stop reading and go write that code.