Orient deformer along curve?

[Kokosing]

Hi, I’m a little bit stumped by this (basic I think) question:

 

I’m using a Sweep to create geometry from a curve. Using Carve, I’m animating the length of it. (Imagine a growing brush stroke)

 

I’d also like to position a deformer at this leading edge to vary it as it grows. 

 

So I’ve used a wrangle with sampleuv to get position information along the curve at the leading edge as it animates. I’d like to use this to position the deformer. I’d also like to orient the deformer so that it aims down the curve. 

 

So two questions:

 

Is there a way to animate the deformer A’s position with an attribute from a curve?

 

And what sort of information would I need to sample from the curve in order to orient the deformer (and how would I apply this?)

 

Many thanks for any ideas (or alternative suggestions) !

 

-Will