Abstract. I will explain a method of constructing BPS algebras for string theory on generic toric Calabi-Yau threefolds. The approach is a "bootstrap" method based on the 3D colored crystals that describe BPS states of the system. The resulting algebras are quiver Yangians Y(Q,W) that are associated with the quiver and the superpotential of the theory. Time permitting, I will also discuss alternative approaches such as gluing methods.