microlux calculates the binary lensing light curve and its derivatives both efficiently and accurately. The code uses Jax (ascl:2111.002) and the modified adaptive contour integration in VBBinaryLensing (ascl:1809.004) to maximize performance. With the access to the gradient, more advanced algorithms can be used for microlensing modeling, such as Hamiltonian Monte Carlo (HMC) in numpyro.