Interesting! Do you mean VSTs? What framework are you using?

I looked at JUCE but find it intimidating. I'm trying Blue Cat Audio Plug'n Script and it seems quite simple for now. We'll see.

I also make simple MIDI scripts in Reaper but they are limited to just this DAW of course.

Do you have products out there yet?

I'm using JUCE. It is intimidating at first, but it's not that bad once you get a hang of it. It's just not something you'll pick up in an afternoon. Of course, if you don't know C++, that's more learning curve.

I'm working on product #1 right now, and probably won't be released for another month. It takes an astounding amount of detail to build plugins, and I'm going to share it with friends for beta testing before I release it.