Apollo is a self-hosted game streaming server, forked from Sunshine and rebranded for compatibility with Artemis (formerly Moonlight Noir) clients. In production, it captures the host's display (via DXGI, KMS, Wayland, or NvFBC), encodes video using hardware encoders (NVENC, AMD AMF, Intel QSV, VAAPI, VideoToolbox) and audio (Opus), then streams over the network using a combination of RTSP for session control and ENet for real-time transport. It also forwards keyboard, mouse, gamepad, and pen input back to the host, enabling low-latency remote gaming or desktop control. The architecture is a single-process C++ application with a multi-threaded design: separate threads for video capture, encoding, audio capture, network I/O, and control. It exposes a web-based configuration UI (Vue.js frontend served by an embedded HTTPS server) and implements the NVIDIA GameStream HTTPS API for client pairing and session management. Platform-specific code is isolated behind abstraction interfaces (e.g., platf::display_t, platf::input_t), with dedicated implementations for Windows, Linux, and macOS. External dependencies include Boost, FFmpeg, OpenSSL, ENet, and vendor-specific SDKs (NVENC, AMF, VAAPI, etc.). The codebase demonstrates solid engineering with a clear separation of concerns, a comprehensive build system (CMake with platform macros), and a growing test suite (Google Test). However, it carries technical debt from its forked nature—some code still references 'Sunshine' while branding leans toward 'Apollo'—and there are incomplete features on macOS (e.g., placeholder functions for clipboard) and fragile workarounds for driver bugs. Overall, it is a functional, well-maintained application with reusable patterns for inter-thread communication, resource management, and platform abstraction.