Everett Kaser Software, founded at some time in the late 80's, is still active today, specializing "in logic and puzzle games intended to stretch your mind, not the storage capacity or the speed of your computer." Although they are not mentioned on their official website today, they produced several well known DOS games including Snarf and Hero's Heart.
Official Everett Kaser Software website
Everett Kaser Software's Mobygames page
Games developed and/or published by Everett Kaser Software
Hero's Heart (1994)
Sherlock (1994)
Snarf (1993)
TigerFox (1990)
Solitile (1989)