Interfaces have become an increasingly important part of XSB. The interface from C to Prolog was implemented by David Warren as was the DLL interface; the interface from Prolog to C (foreign language interface) was developed by Jiyang Xu, Kostis Sagonas and Steve Dawson. The XSB-Java interface was written by Miguel Calejo as was the InterProlog user interface. The Oracle interface was written by Hassan Davulcu and Ernie Johnson. The interface to POSIX regular expression and wildcard matching as well as the Libwww-based Web access package was written by Michael Kifer. The interface to Perl pattern matching routines was written by Michael Kifer and Jin Yu. The ODBC interface was written by Lily Dong and Baoqiu Cui.
David Warren and Prasad Rao implemented the aggregate library. The SLX preprocessor was written by José Júlio Alferes and Luís Moniz Pereira. Unix-style scripting libraries were written by Terrance Swift, and the ordset library was written by Richard O'Keefe.