Tianqi Chen worked on optimizing the CI build pipeline for the apache/tvm repository, focusing on improving build and test efficiency. He reconfigured Jenkins jobs to leverage more powerful nodes and eliminated legacy scripts and hardware-specific tests, which reduced build and test times while enabling greater parallelization. Using Groovy and Shell scripting, Tianqi streamlined the CI/CD process and improved resource utilization, targeting both performance and cost savings. His work addressed maintenance overhead by removing obsolete components, resulting in faster feedback loops for developers and more reliable validation cycles. The depth of changes reflected a strong understanding of build systems and automation.