Developer of Macintosh applications since 1985. Long-time developer of TCP/IP and networking software (the principal Macintosh developer on NCSA Telnet). CTO at InterCon Systems, developer of network software for the Macintosh (TCP/Connect, NFS/Share, etc.). CTO at Haste, developer of network optimization for real-time content.

Since 2008, developing GIS applications for Mac and iOS (Cartographica and CartoMobile) as the owner and lead developer for ClueTrust.