The Modules for Experiments in Stellar Astrophysics (MESA) software has been significantly updated to enhance its capabilities in modeling binary systems, pulsations, and supernova explosions. MESA now supports the simultaneous evolution of differentially rotating binary stars with mass and angular momentum transfer, enabling more accurate modeling of binary evolution. It can now simulate advanced burning stages necessary for constructing supernova progenitor models using fully coupled nuclear networks with hundreds of isotopes. Implicit hydrodynamics with shocks is now supported, allowing the modeling of the entire massive star lifecycle, from pre-main sequence evolution to core collapse and nucleosynthesis. The coupling of GYRE with MESA enables new explorations of massive star instability strips and accelerates the use of asteroseismology data. Improved treatment of mass accretion provides more accurate near-surface profiles. A new capability allows for on-the-fly calculation of weak reaction rates, improving simulations of accretion-induced collapse of white dwarfs. Improvements in MESA now allow for the simulation of radiative levitation of heavy elements in hot stars. MESA provides bit-for-bit consistency across platforms, enabling rapid development. MESA now includes the ability to evolve binary systems, with new capabilities for orbital angular momentum evolution, mass transfer from RLOF, and the effects of tides and accretion on stellar spin. It also includes improved treatment of thermohaline mixing in accreting models and numerical tests to validate the implementation of physics. The software also includes new capabilities for advanced burning and X-ray bursts with large, in situ reaction networks. MESA models the pre-supernova evolution of massive stars and combines implicit hydrodynamics with advanced burning to probe nucleosynthesis and yields of core-collapse supernovae. It also includes improvements for mass accretion, weak reaction rates, and particle diffusion. The software infrastructure provides bit-for-bit consistency across platforms, enabling rapid development. The paper outlines the new capabilities of MESA in modeling binary systems, pulsations, and supernova explosions.The Modules for Experiments in Stellar Astrophysics (MESA) software has been significantly updated to enhance its capabilities in modeling binary systems, pulsations, and supernova explosions. MESA now supports the simultaneous evolution of differentially rotating binary stars with mass and angular momentum transfer, enabling more accurate modeling of binary evolution. It can now simulate advanced burning stages necessary for constructing supernova progenitor models using fully coupled nuclear networks with hundreds of isotopes. Implicit hydrodynamics with shocks is now supported, allowing the modeling of the entire massive star lifecycle, from pre-main sequence evolution to core collapse and nucleosynthesis. The coupling of GYRE with MESA enables new explorations of massive star instability strips and accelerates the use of asteroseismology data. Improved treatment of mass accretion provides more accurate near-surface profiles. A new capability allows for on-the-fly calculation of weak reaction rates, improving simulations of accretion-induced collapse of white dwarfs. Improvements in MESA now allow for the simulation of radiative levitation of heavy elements in hot stars. MESA provides bit-for-bit consistency across platforms, enabling rapid development. MESA now includes the ability to evolve binary systems, with new capabilities for orbital angular momentum evolution, mass transfer from RLOF, and the effects of tides and accretion on stellar spin. It also includes improved treatment of thermohaline mixing in accreting models and numerical tests to validate the implementation of physics. The software also includes new capabilities for advanced burning and X-ray bursts with large, in situ reaction networks. MESA models the pre-supernova evolution of massive stars and combines implicit hydrodynamics with advanced burning to probe nucleosynthesis and yields of core-collapse supernovae. It also includes improvements for mass accretion, weak reaction rates, and particle diffusion. The software infrastructure provides bit-for-bit consistency across platforms, enabling rapid development. The paper outlines the new capabilities of MESA in modeling binary systems, pulsations, and supernova explosions.