Sunnyside Soft was a small software company in Fresno, California. Quite possibly its name was based on the local high school, Sunnyside High. Sunnyside Soft consisted of two husband/wife pairs: Al and Margaret Lowe and Mike and Ray Lynn MacChesney. Al, a music teacher at the time, had invested in an Apple II computer to learn how to program and, together with the others decided to develop educational games for children. Together they made Dragon's Keep and Troll's Tale for the Apple II. Al did the programming while the others were credited for writing and graphics. For the graphics of both games they used Penguin Software's "The Graphics Magician".
When Sunnyside Soft displayed their games at Applefest 1982, Sierra On-Line founders Ken and Roberta Williams were also present. Noticing how Sunnyside Soft's games looked graphically similar to their own Hi-Res Adventures, they introduced themselves - the beginning of a lifelong friendship between the Williams and Lowes. They agreed to publish the Sunnyside Soft titles through Sierra On-Line and also ported them to the Atari 400/800 and Commodore 64 and, in case of Troll's Tale, also to the IBM PC with enhanced graphics.
While Al Lowe continued to work for Sierra for another 15+ years, developing Sierra's Disney Software titles for a few years and later on creating the infamous Leisure Suit Larry series and other titles, the other members of Sunnyside Software had a shorter role at Sierra. Margaret Lowe is credited for the music for both King's Quest III (1986) and Police Quest I EGA (1987) (which has a similar theme song). Mike and Ray Lynn's only other game credit was for Gelfling Adventure, an adaptation of Hi-Res Adventure #6, Jim Henson's Dark Crystal.