shadPS4 is a PlayStation 4 emulator for Windows, Linux, and macOS, written in C++20. It emulates the PS4's AMD GCN GPU via a custom shader recompiler that translates GCN instructions to SPIR-V, and implements high-level emulation (HLE) of PS4 system libraries (kernel, libc, networking, audio, video, input, etc.). The architecture is monolithic with modular subsystems: a Vulkan renderer with texture/buffer caches, a shader recompiler with IR optimization passes, a file system abstraction supporting host files and ZArchive, and an ImGui-based debug UI. While many library functions are stubbed or partially implemented, the core GPU and CPU emulation is functional enough to run several commercial games. The codebase demonstrates strong engineering practices with reusable common utilities (bitfields, slot containers, thread-safe queues) and a well-structured shader compilation pipeline. It is a hybrid project, combining software application development with significant reverse-engineering and data analysis of PS4 firmware and GPU architecture.