Bounded Balance Delta Composition on Solana

A transaction that chains several on-chain operations may need to size a later operation from the amount an earlier operation actually produced. This paper evaluates lp-zap, a bounded Solana cross-program invocation composer that snapshots selected account balances, patches eight-byte fields in later instruction data, and enforces signed terminal balance bounds. The study uses a pinned source revision and preserved local experiments from 11 October 2026. In a matched two-transfer Mollusk fixture, the generic composer consumed 5,799 compute units versus 2,870 for a specialized Pinocchio implementation, with identical final balances and rollback after a failing terminal bound. A controlled comparison within the composer attributed 377 compute units to introducing a measured-delta patch in that fixture. Deterministic host testing covered 100,000 parser cases and 100,000 arithmetic cases, alongside targeted runtime alias tests. A concrete limitation is the eight-byte patch width: the recorded Meteora DAMM v2 liquidity calculation can exceed 64 bits even for a one-unit input. These results characterize the cost and boundaries of one implementation. They do not establish universal venue compatibility, mainnet compute costs, a general security proof, or novelty of atomic transactions and dynamic call chaining. Preparation of this report was assisted by Codex. The research programme is directed toward human agency, financial inclusion, and evidence-based accountability. Intended social benefits are distinguished from measured technical results in the manuscript. The manuscript and newly authored analysis are offered under CC BY 4.0. Any supplied source files retain the license terms stated in the supplement; the record license does not replace third-party source licenses.