Fuzzilli vs Onyx Launcher
Fuzzilli
github.comOnyx Launcher
github.comSide by side
| Figure | Fuzzilli | Onyx Launcher |
|---|---|---|
| Price from | Free | Free |
| Free plan | Yes | Yes |
| Free trial | — | — |
| Open source | — | — |
| Windows | — | Yes |
| macOS | Yes | — |
| Linux | Yes | Yes |
| Self-hosted | Yes | — |
| Plans published | 1 | 1 |
| Spec score · Fuzz Testing Software | 8.4 (#6) | 7.9 (#10) |
| What it does | Fuzzilli is a coverage-guided fuzzer for dynamic language interpreters, built around a custom intermediate language called FuzzIL that can be mutated and translated to JavaScript. | Onyx is an open-source desktop Minecraft launcher built with React and Electron. |
Plans
In their own words
Fuzzilli
Fuzzilli is a free, open-source, coverage-guided fuzzer for dynamic language interpreters. It represents test programs in FuzzIL, mutates them, and translates them to JavaScript for execution. Its mutators can change data flow or operation parameters, generate or splice code, and combine corpus programs. Components include a mutation fuzzer, script runner, corpus, environment, minimizer, evaluator, and lifter. A target engine runs repeated scripts in a read-eval-print-reset loop, resetting between cases; multiple instances can synchronize within a process or across machines over TCP. Listed target directories include JavaScriptCore, JerryScript, QuickJS, QtJS, Serenity, SpiderMonkey, V8, XS, Duktape, and njs. Setup requires compiling a supported engine with coverage instrumentation using clang 4.0 or later, then building Fuzzilli with Swift Package Manager. Docker and Google Compute Engine tooling are provided. The project supports Linux, macOS, and self-hosted use and identifies its license as Apache-2.0. Its repository says it is not an officially supported Google product. Contributions require a Contributor License Agreement and are reviewed through GitHub pull requests.
Onyx Launcher
Onyx Launcher is a free, open-source desktop Minecraft launcher for Windows and Linux. It manages separate instances, imports modpacks and supports Fabric, NeoForge, Forge, Quilt and Vanilla. A built-in Modrinth catalog lets users browse, install and update mods and modpacks, while automatic updates and Java runtime management are included. Onyx can detect, download and isolate Eclipse Temurin Java 8, 17 or 21 as needed. Diagnostic features measure in-game FPS, average frame times and stutters, analyze logs, track memory and garbage-collection pauses, and use Crash Bisect to look for conflicting mods through controlled launches. World Guard creates safety snapshots before risky operations and supports rollbacks. Ghost Mode unloads the launcher window, WebContents and GPU processes from memory when Minecraft starts. Microsoft sign-in uses OAuth Device Flow, and offline mode with custom skins is available. Windows builds are currently unsigned; published SHA-256 checksums can be checked. The MIT-licensed project says it is independent of Microsoft, Mojang Studios and Modrinth.