The CORSIKA8 simulation framework, a successor of the well-known Monte Carlo air-shower simulation CORSIKA7, is a state-of-the-art implementation and testbed for the simulation of particle cascades from air to dense media. With its modular architecture, not only standard cascade simulation is possible, but a variety of additional mechanisms can be utilized. The Radio module, as one of the integral core components, implements two methods: the "Endpoint formalism" and the "ZHS algorithm". Recent simulation studies utilizing the common environment have demonstrated good agreement, as low as 2\%, between both methods. Comparisons with CoREAS (CORSIKA7) and ZHAireS confirm the validity of the generated results and their use as a precision tool for air-shower simulation.

This contribution highlights recent development efforts with a focus on extending capabilities beyond standard air-shower simulations. A particular highlight is the electromagnetic wave propagation through complex and inhomogeneous media, including cross-media showers, achieved through full ray tracing. In addition, there is an ongoing work to implement full electrodynamic field propagation through glacial environments with Eisvogel for highly realistic simulations.

Further effort has been taken to improve the computational performance of large-scale simulations; this includes computational improvements as well as reduction and prioritization through dynamic stack-based sorting. The implementation of the ARZ method for semi-analytic treatment of radio emission in dense media, avoiding costly propagation routines, is presently tested.
The current and ongoing work in the extensible CORSIKA8 framework makes it ideally suited for future studies on radio detection of a wide variety of particle cascades.