Google has cut code migration time in half by deploying AI tools to assist with large-scale software updates, according to a new research paper from the company’s engineers. The tech giant used large language models to help convert 32-bit IDs to 64-bit across its 500-million-line codebase, upgrade testing libraries, and replace time-handling frameworks. While 80% of code changes were AI-generated, human engineers still needed to verify and sometimes correct the AI’s output. In one project, the system helped migrate 5,359 files and modify 149,000 lines of code in three months.