Introduction

libretro-core-rs is a Rust workspace for writing libretro cores without making core authors work directly against the C ABI.

A libretro core is a dynamic library loaded by a frontend such as RetroArch. The frontend owns the window, audio device, input mapping, and optional OpenGL context. The core owns the emulation or application state, reports metadata and AV timing, accepts content, and produces one frame of video and audio whenever the frontend calls it.

The public API is intentionally Rust-first. Normal core code should use enums, newtypes, builders, slices, owned strings, Option, and Result instead of raw callback tables, magic numbers, unchecked pointers, or hand-written retro_* exports.

The project has two library crates:

• libretro-core, imported as libretro, owns the Core trait, export_core! macro, typed libretro wrappers, runtime helpers, input polling, callback event routing, environment commands, and OpenGL symbol wrappers.
• libretro-diagnostics owns optional visible diagnostics for cores that want clear failure frames instead of silent black screens.

Read the tutorial chapters in order if you are starting a core from scratch. Use the API reference when you already know the libretro concept and need exact entry points.

Useful local references:

• Libretro In Rust
• Hello World Core
• Rustdoc Map
• Local Libretro Specs