Allegro Common Lisp is a full ANSI Common Lisp (1994) implementation. It contains many extensions, including 32- and 64-bit native compilation, efficient built-in memory management, foreign functions (for interfacing with other languages), multiprocessing, UNICODE and locale support, XML/HTML parsers, a Web client and server, GTK+ interface (1.2 and 2.0), Java interface, OLE interface (Windows only), profiler, regular expressions, an XML RPC implementation, native Lisp RPC, sockets, DLL and shared library support, and more.
lns.http is a simple framework for writing Common LISP Web applications. It handles the incoming connections, parses HTTP headers and queries, and finally hands control over to your URL handler. It is an HTTP/1.1 compatible Web server, but tries to achieve compatibility with lesser (down to the informal HTTP/0.9) clients.