Papyrus Client

Fabric-only Minecraft launcher for macOS and Windows with Microsoft sign-in, mod management, and a bundled client integrity mod that reports installed mods to Papyrus servers.

Documentation: docs.sushii.dev/papyrus-client

Supported mod builds: 26.1.2, 1.21.11, 1.21.10, 1.21.8, 1.21.4, 1.21.1 (see SUPPORTED_VERSIONS.txt).

Components

Path	Description
launcher/	Electron launcher (Microsoft auth, Fabric install, mod profiles)
mod/	Fabric mod papyrus-shield for obfuscated 1.21.x
mod-unobf/	Same mod sources for unobfuscated 26.1.2

Downloads

Releases publish:

• Launcher — Papyrus-Client-<version>-mac.dmg, Papyrus-Client-<version>-win.exe
• Mod only — papyrus-shield-<minecraftVersion>-<modVersion>.jar (e.g. papyrus-shield-26.1.2-1.0.0.jar)

Build locally

Requires Gradle 9.5+ (wrapper is generated on first build). Use Java 21 for mod/ (1.21.x) and Java 25 for mod-unobf/ (26.1.2).

# Obfuscated versions (1.21.x)
cd mod && gradle wrapper --gradle-version 9.5 && ./gradlew build

# 26.1.2 (unobfuscated, Java 25)
cd mod-unobf && gradle wrapper --gradle-version 9.5 && ./gradlew build

# Launcher
cd launcher && npm install && npm run build

Server integration

Papyrus servers enable anticheat.client-integrity in paper-global.yml. Players without the client mod are kicked with a link to the docs download page.