In accordance with the present invention, a system, method, and computer-readable medium for identifying malware in a request to a Web service is provided. One aspect of the present invention is a computer-implemented method for protecting a computer that provides a Web service from malware made in a Web request. When a request is received, an on-demand compilation system compiles high-level code associated with the request into binary code that may be executed. However, before the code is executed, antivirus software designed to identify malware scans the binary code for malware. If malware is identified, the antivirus software prevents the binary code associated with the request from being executed.