During March 2025, work focused on enhancing the Hardvan/Java repository by developing a linear system solver for equations of the form Ax=b. The solution applied Gaussian elimination with partial pivoting to improve numerical stability, followed by a back substitution phase. Singular matrices were explicitly handled by introducing input validation that throws an IllegalArgumentException when necessary. Comprehensive unit tests were integrated to verify solver correctness across a range of matrix scenarios, ensuring reliability and robustness. This feature, implemented in Java and leveraging skills in algorithm implementation, linear algebra, and numerical methods, strengthened the repository’s core mathematical and testing capabilities.