  We present new stellarator equilibria that have been optimized for reduced
turbulent transport using nonlinear gyrokinetic simulations within the
optimization loop. The optimization routine involves coupling the
pseudo-spectral GPU-native gyrokinetic code GX with the stellarator equilibrium
and optimization code DESC. Since using GX allows for fast nonlinear
simulations, we directly optimize for reduced nonlinear heat fluxes. To handle
the noisy heat flux traces returned by these simulations, we employ the
simultaneous perturbation stochastic approximation (SPSA) method that only uses
two objective function evaluations for a simple estimate of the gradient. We
show several examples that optimize for both reduced heat fluxes and good
quasisymmetry as a proxy for low neoclassical transport. Finally, we run full
transport simulations using the T3D stellarator transport code to evaluate the
changes in the macroscopic profiles.
