It would be mind blowing if that PLC is able to work with uLisp. I was trying to learn about industrial automation and it turn out that the standard is: IEC 61131-3.
The “most advanced language” available here is ST: ST. “It is a high level language that is block structured and syntactically resembles Pascal” so horror history. It is like the automation industry remain in the 60’s. Maybe some day someone can generate a transpiler from lisp to ST.
In any case, by being able to program a PLC with uLisp is a perfect example of Paul Graham power language hierarchy theory. Which is fun since these Arduino based PLCs are mostly intended for maker / starter projects. “Best Industry” practice is going with IEC_61131-3 for production projects.