GoNES vs JSNES

GoNES is a free, open-source NES emulator written in Go. It runs on Windows, macOS, Linux and web browsers; the browser version compiles to WebAssembly, and the project links to a hosted instance. At startup, the app opens a file picker for selecting a .nes ROM, and it can also be launched from a terminal with a ROM file argument. The project lists support for mappers 0, 1, 2, 3, 4, 7, 69 and 71, which it says cover 84.34% of official NES games. Keyboard controls for two players are configurable. Save-state, load-state and undo bindings are listed. GoNES creates a configuration file on first run, with its location documented for each desktop platform. Release downloads are provided, and macOS installation through Homebrew is documented. Source installation is also documented. Building requires OpenGL development libraries because rendering uses Ebitengine. The project says its GUI renders, but menu options still need to be added.

JSNES is a free JavaScript library for emulating NES games in browsers and Node.js. Its Browser helper handles canvas rendering, audio, keyboard and gamepad input, and frame timing; the lower-level NES class allows custom rendering and audio handling in Node.js. ROM data can be loaded from a URL or from a string, Uint8Array, or ArrayBuffer. The API runs frames, accepts controller input for either player, resets, adjusts frame rate, and includes methods for moving and triggering the Zapper. Applications can serialize and restore emulator state with `toJSON()` and `fromJSON()`. The `onBatteryRamWrite` callback lets an application capture battery-backed SRAM writes for persistent game saves. Sound emulation is enabled by default, with a default sample rate of 48000 Hz, and an audio callback is available. The README provides npm installation for Node.js or Webpack and an unpkg script for browser use, as well as a React embedding example. JSNES is licensed under Apache-2.0; its GitHub Issues tracker accepts bug reports and feature requests.