JS Stack Overflow / Increase

I'm afraid you can't increase the stack without rebuilding the firmware to decrease the amount of JsVars available. Which board are you running on?

The interpreter is recursive-descent, so it does use up a bunch of stack for each function call. About 10 levels deep does sound about right. There are few ways around having so many stacked calls though:

• use on/emit to send out events if you don't need a response
  
• use Promises
  
• add setTimeout(...,0) when to call a function - if you could do this halfway up your call stack you'd effectively split it in two