May 2026 monthly summary for stryker-net focusing on correctness and regression coverage improvements in mutation testing outcomes. - Implemented Accurate Mutation Testing Outcome Classification: corrected handling so tests ending in error, timeout, or cancelled states are reported as failures, preventing mutants from being misclassified as Survived. Centralized classification logic in the internal TestNodeStates helper and extended coverage to Timeout scenarios with TimedOutTests. - Expanded regression test coverage: added 29 unit tests across all possible per-test states to ensure robust regression coverage; confirmed classifier changes are regression-safe. - Verified business impact with downstream verification: apples-to-apples comparison against a downstream TUnit + NSubstitute project showed baseline 42.99% -> fixed 53.39% strict score on the same mutant set, with 23 mutants moved from Survived to Killed and no drift elsewhere. - Delivery context: supports more reliable mutation scores, reducing false positives/negatives, and improving CI feedback loops for the mutation testing workflow. - Co-authored implementation and validation with multiple contributors, with explicit mapping and regression coverage demonstrated in the commit 58969ca79a816587945141383309adbe60de6778.