Adventures in Automated Smart Contract Testing: A Spark Is Born

Fri, 19 Jun 2026 00:00:00 +0000

TL;DR. We proved the core accounting math of Spark’s PSM3 (share price, conversions, swap quotes) against the real bytecode: sixty properties, verified for every input up to uint128. The proofs run in Echidna’s verification mode on top of hevm’s arithmetic abstraction, which is still experimental code, in review as argotorg/hevm#1075. All the verification code is in our spark-psm branch if you want to check it. What resisted exact proof got monotonicity and rounding bounds that still rule out the attacks; everything else went to a fuzzing campaign: some 80 hours and roughly 700 million executions against the repo’s own fuzz tests and eight stateful invariants. All clean, except one small bug in the invariant harness itself. Prove the core, fuzz the rest.

Formal-Verification on Gustavo Grieco: blockchain security researcher

Adventures in Automated Smart Contract Testing: A Spark Is Born