Jazzer vs Onyx Launcher
Jazzer
github.comOnyx Launcher
github.comSide by side
| Figure | Jazzer | Onyx Launcher |
|---|---|---|
| Price from | Free | Free |
| Free plan | Yes | Yes |
| Free trial | — | — |
| Open source | Yes | — |
| Windows | Yes | Yes |
| macOS | Yes | — |
| Linux | Yes | Yes |
| API | Yes | — |
| Self-hosted | Yes | — |
| Plans published | 2 | 1 |
| Spec score · Fuzz Testing Software | 8.6 (#4) | 7.9 (#10) |
| What it does | Jazzer is an in-process, coverage-guided fuzzer for JVM applications, built on libFuzzer techniques. | Onyx is an open-source desktop Minecraft launcher built with React and Electron. |
Plans
In their own words
Jazzer
Jazzer is a free, coverage-guided fuzzer for JVM applications, running in-process and based on libFuzzer. It supports Java, Kotlin, Scala, and Clojure targets, as well as JNI and native libraries. With JUnit 5.9.0 or newer, fuzz tests can run alongside regular unit tests. The @FuzzTest annotation lets Jazzer generate and mutate method inputs, including primitives, strings, arrays, and standard library classes. JUnit fuzz tests can use saved crashing inputs in regression mode or generate and mutate inputs to explore coverage. Built-in sanitizers detect Java security issues such as SSRF, file path traversal, and OS command injection, and provide feedback to guide fuzzing. The README documents use with Maven, Gradle, and Bazel. Jazzer can also run as a standalone binary or through its Java main class. Supported systems are Linux x86_64 and arm64, macOS 12 or newer on x86_64 and arm64, and Windows x86_64. The jazzer-junit package is available on Maven Central, and the repository identifies the project as licensed under Apache-2.0.
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.