Oscar Insurance Corp., the health insurance startup whose cartoon ads promise an easier way of getting medical care, hired Alan Warren from Google as chief technology officer to help it improve its underlying computer systems. Warren, 59, started March 7 in a role left open after technology chief Fredrik Nylander left in June. Warren will also serve as senior vice president of engineering, Oscar Chief Executive Officer Mario Schlosser said in a blog post. At Google, which is part of Alphabet Inc., Warren helped expand the company’s New York office and oversaw Google Docs and Google Drive.