In this talk I will present recent and future developments of FLASH, an open source, multi-physics, finite-volume, shock capturing code with a broad range of capabilities.  The code has recently been extended to tackle high-energy physics (HEDP) problems, such as laser-driven laboratory experiments, transforming it into a powerful tool for the HEDP community, both in academia and national labs.  I will discuss the implementation and verification of these new physics capabilities, and detail some of the algorithmic developments in store for the future of the code, such as high order in space and time methods and alternative magneto-hydrodynamics (MHD) algorithms that will enhance its robustness and accuracy.  The code will also be showcased through simulations of selected HEDP problems, performed using leadership-class computing platforms, which assess its validity against experimental results and demonstrate its value in experiment design and analysis.