The NiSi 15mm f/4 lens was announced a few months ago for Sony, Nikon, Canon, and Fujifilm mounts. Yesterday (4/15!) NiSi released the 15mm f/4 lens also for L-mount. For pricing and availability check Adorama, Amazon, and B&H (the new lens is not listed at the time of post).
Additional information on the NiSi 15mm f/4 lens can be found here:
