Feather 🪶¶

Real-time debug & inspect tool for LÖVE (love2d) games.

Like Flipper or React DevTools, but for LÖVE game. Inspect logs, variables, performance metrics, and errors in real time over a WebSocket connection with a built-in plugin system, step debugger, and zero-config setup.

Features¶

• 📜 Live log viewer — See print() output instantly in the app.
• 🔍 Variable inspection — Watch values update in real-time.
• 🚨 Error capturing — Catch and display errors automatically.
• 📸 Screenshots & GIF capture — Capture screenshots and record GIFs via the built-in plugin.
• 🔌 Plugin system — +18 built-in plugins + custom ones. Server-driven UI: plugins define their actions in Lua, the desktop renders them automatically.
• 📱 Multi-session support — Connect multiple games simultaneously, each gets its own session tab.
• 📲 Mobile debugging — Auto-detected local IP in Settings with copyable connection string.
• 💻 Console / REPL — Execute Lua code in the running game (opt-in, requires apiKey).
• 🐛 Step Debugger — Breakpoints, step over/into/out, call stack, and local variable inspection.
• 🖼️ Asset inspector — Browse loaded textures, fonts, and audio sources with previews, zoom, pan, and pixel grid.
• ✨ Texture Lab — Generate tiny PNG sprites, masks, noise maps, gradients, and trail textures for creative workflows.
• 📁 Log file viewer — Open .featherlog files for offline inspection.
• 🖥️ CLI-first workflow — feather init, feather run, and feather remove manage setup and cleanup with no manual Lua integration.
• 🚢 Build/upload helpers — feather build creates .love, web, mobile, and desktop artifacts and feather upload itch pushes them with Butler.
• 🧹 Self-cleaning setup — Generated files are managed by Feather and can be previewed or removed before release.
• 📦 Config file support — feather.config.lua keeps project settings outside game code.

Quick Start¶

Install the Feather desktop app and CLI:

1. Download the desktop app from Releases.
2. Install the CLI:

npm install -g @kyonru/feather

Initialize your project, open the Feather app, then run the game:

feather init path/to/my-game
feather run path/to/my-game

Feather is injected by the CLI for dev runs and debug builds, so your game code does not need a manual require for any target.

By default, CLI init enables error capture and includes the creative plugins particle-system-playground and shader-graph. Other plugins are controlled through feather.config.lua:

feather config plugins --include input-replay --dir path/to/my-game
feather config hot-reload --allow game.player --dir path/to/my-game

Optional Vendors¶

Vendor setup downloads the local LÖVE runtimes/templates needed by web, mobile, and packaged desktop targets, then updates feather.build.json.

feather build vendor add web --dir path/to/my-game
feather run path/to/my-game --target web

feather build vendor add android --dir path/to/my-game
feather run path/to/my-game --target android

feather build vendor add ios --dir path/to/my-game
feather run path/to/my-game --target ios

For all build vendors, including desktop packaging runtimes:

feather build vendor add all --dir path/to/my-game

Build release artifacts from the same CLI flow:

feather build love --dir path/to/my-game --release
feather build android --dir path/to/my-game --release
feather build ios --dir path/to/my-game --release
feather build windows --dir path/to/my-game --release
feather build macos --dir path/to/my-game --release
feather build linux --dir path/to/my-game --release
feather build steamos --dir path/to/my-game --release

See CLI for feather run, feather doctor, feather build, and feather upload options.

Documentation¶

• CLI — Run games without touching their code, feather run, feather init, feather doctor, feather build, feather upload
• Installation — Download, install script, LuaRocks, custom paths
• VS Code Extension — Run, doctor, build, plugin, package, and project settings from the editor
• Usage — Quick tour of the desktop app and common workflows
• Configuration — Runtime options, auth, runtime budgets, connecting, mobile debugging
• MCP — Local AI client access to sessions, plugins, Shader Graph, Particles Playground, and Texture Lab
• Session — Connection health, auth/config status, suspend/resume, session switching
• Logs — Live logs, follow-tail, persistence, filters, .featherlog files
• Observability — observe, watch, diffs, history, exports, and payload-cost guidance
• Performance — Health metrics, Feather overhead, runtime budgets, profiler entry points
• Profiler — Core profiler captures, snapshots, probes, wrapped functions, run comparisons
• Debugger — Breakpoints, stepping, pause-on-error, source views, profiler probes
• Console — Opt-in Lua eval, result inspectors, pins, read-only guardrails
• Assets — Inspect loaded textures, fonts, audio, previews, and game-root mapping
• Particle System Playground — Particle templates, timelines, previews, exports
• Shader Graph — Node graph shaders, templates, previews, connected-game apply
• Texture Lab — Procedural PNG sprites, masks, noise maps, spline paths, gradients, and trail textures
• Standalone Showcase — Browser-hosted creative tools without a local game
• Time Travel — Observer snapshot recording and timeline scrubbing
• Session Replay — Input replay with developer-selected state checkpoints
• Package Management — Curated LÖVE packages, trust, checksums, lockfiles
• Plugins — Built-in plugins, plugin system, custom plugins
• Recommendations — Security, performance, release builds

Screenshots¶