I've been making use of this excellent extension for hatching - https://inkscape.org/~Moini/%E2%98%85hatch-fill+1

I does about 98% of what I need for preparing svg files for laser burning. I've made some modifications to the code so that I can use the generated output for my post processing scripts.My post processing scripts recalculates the size and auto-centers the gcode (I primarily burn on round objects) as well as adjusts the laser intensity based on the fill color of the svg objects.To achieve this, I modified the code above to set the hatch ID values to a name that incorporates the color and removed the original fill attribute. I also created the outline stroke if it is not already present.

It's a fairly minor revision to the code but it speeds up my workflow considerably.

I'd like to share it but I'm not sure how. It seems so minor that a full fork of the original eggbot code is not really warranted. 

Any suggestions for making this available to the community?