Molecular self-assembly provides promising nanomaterials because they are water-processable, the constituent molecules are modular and scalable, and their surfaces can be easily functionalized. However, supramolecular nanomaterials generally exhibit high molecular exchange rates, hydrolytic degradation, and other instabilities that preclude their use in the demanding environments or the solid state. Here I introduce a new self-assembled nanofiber platform, recently developed in our lab, that exhibits unprecedented mechanical strength and dramatically reduced dynamic instabilities. The nanofibers have widths less than 6 nm, length of many microns, and pristine internal molecular order. In this talk, I will discuss the design and characterization of this platform and the possible new application space that is enabled by such enhanced stability.