Takuya Kiriyama focused on stabilizing Java test environments by addressing platform-specific issues in open source JVM projects. In corretto/corretto-21, he resolved encoding-dependent failures in NewLineTest by adapting the test to use native character encoding, which improved cross-platform determinism and reduced flakiness in Windows Japanese locales. Later, in SAP/SapMachine, he enforced a 256MB heap limit for 32-bit test runs within the TestMemoryOptions suite, ensuring consistent JVM behavior and more reliable CI outcomes. His work demonstrated proficiency in Java development, build tools, and testing, delivering targeted bug fixes that enhanced test reliability and code quality across architectures.