In a small bowl or liquid mesauring cup, mix ¼ cup cold water with xanthan gum or gluccie (sprinkle on the xanthan gum or gluccie to prevent clumping; if clumps happen anyway, smash them to smithereens with the back of a spoon). Set aside.
Whisk remaining water, sweetener, and salt together in a saucepan. Bring to a boil. Remove from heat.
While whisking, mix in the xanthan gum or gluccie water.
Stir constantly until it begins to thicken.
Whisk in maple flavoring and vanilla.
Mixture should thicken more as it cools. If you'd like it to be thicker, add more xanthan gum or gluccie a pinch at a time (remember to sprinkle it in and smash its clumps).
Store in an airtight container in the fridge.
Notes
If the syrup comes out lumpy from the xanthan gum, run it through a blender for a bit to break it up.