Gas audit of Spark Savings finds 12-18% fee reduction possible without compromising security

An external security research team audited the Spark Savings lending and yield-aggregation protocol, which holds roughly $1.4 billion in total value locked across Ethereum and Layer 2 networks. The review focused on gas-heavy code patterns in its core contracts, including storage layout, loops, external token calls, and error handling. Auditors estimate the recommended changes could cut gas use by about 12% to 18% per typical deposit or withdrawal, saving users roughly $0.45 to $0.70 on Ethereum and $0.12 to $0.20 on Optimism or Arbitrum. The report also warns that aggressive gas-saving techniques, such as unchecked arithmetic, reordered external calls, and unbounded batch functions, could introduce security risks if not carefully constrained. Each risk is paired with suggested mitigations, such as restricting unchecked math, keeping safe call ordering with reentrancy guards, and capping batch sizes.