How do I install Crimes Against the JVM?

Install the matching mod loader (Forge, Fabric or NeoForge) for your Minecraft version. Download the .jar. Put it in the .minecraft/mods folder and launch that loader profile. Opens on Modrinth — not every file is mirrored on our own servers.

What Minecraft version does Crimes Against the JVM work with?

The listing gives Minecraft 1.21.1. This is the version stated by the author or source site, not something we verified ourselves.

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ModsJava

Crimes Against the JVM

by transgender · on Modrinth

Execute arbitrary bytecode (client-only!) from books you wrote. Because funny. Now compatible with Sinytra Connector & Forgified Fabric API!

⬇ Download on Modrinth

Open in MC Java Mods Get it on Google Play →

THIS IS CLIENT ONLY

Execute arbitrary JVM bytecode from books you wrote (Has to be your PlayerEntity as the author for security reasons) - just hold it in your offhand and press the key (Unbound by default, also for security reasons.)

Will not run on servers, for hopefully obvious reasons.

Quick facts

Edition: Minecraft Java
File type: .jar
Minecraft version listed: 1.21.1
How to install: Install the matching mod loader (Forge, Fabric or NeoForge) for your Minecraft version. → Download the .jar. → Put it in the .minecraft/mods folder and launch that loader profile.
Where to get it: Opens on Modrinth — not every file is mirrored on our own servers.

Install steps are the general flow for this file type — How to install Minecraft Java mods & modpacks walks through it step by step.

Verified by MCModsHub

Ships as catj-1.0.0.jar — drop this file into the mods folder
Download size: 25 KB
Download link checked 31 Aug 2026 — working

These come from our own check of the pack file, not from the source page.

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