I have developed a very weak chess program for young kids bellow age of ten, which simulates kids of 6,7,8 years. I decided to put position to it and even it took some advantage immediately. And ten years back there were already many strong engines around. Even twenty years back Fritz 2 and 3 ( on DOS) were playing like masters. Chess Master 2000 was also fairly good.
I still have many such programs. Many of them can still work.
Houdini's Houdini. It's not a chess program, it's a god