A method for extending the capabilities of an arbitrary web server operating in a client-server environment (e.g., the Internet). When a client makes a request to the web server, the request may include an address for a code module needed to service the request. If the code module is not available at the web server, the web server uses the address to request the code module from another location. The code module is then served to the web server and installed. The web server then responds to the original client request using the installed code module. In an alternative embodiment, the code module is uploaded to the target server from the client.