A Calagopus Panel extension that makes installing and managing Minecraft mods easy. Browse Modrinth, install mods with one click and manage everything in the server's mods folder, all from the server's Mods page.

Package name: dev.caloptreyx.modinstaller · Requires panel >=1.2.2

• Browse Modrinth mods with search, mod loader and Minecraft version filters, sorting and a server-side-only toggle. Filters start at the server's detected mod loader and Minecraft version.
• Manage installed mods: every .jar in mods/ is identified on Modrinth by its file hash and shown with its icon, name and version. Search the list and filter it by status.
• Enable or disable a mod with one switch. Disabled mods are renamed to <file>.jar.disabled, so the mod loader skips them.
• Switch the version of an installed mod. The new file keeps the old file's enabled state, and the old file is only removed after the new one has downloaded.
• Detection badges show the server's detected mod loader (Fabric, Quilt, Forge, NeoForge) and Minecraft version. Hover a badge to see where the value was detected.
• An alert appears when the mod loader or Minecraft version can't be detected.
• Mod Details page with the full description and a Versions tab. The tab lists every version in a table and supports search, loader/Minecraft version/channel filters and pagination.
• Install Mod modal where you pick the mod loader, Minecraft version and mod version. The choices default to the detected mod loader and Minecraft version, and a warning appears when your choice doesn't match the server.

Download dev_caloptreyx_modinstaller.c7s.zip from the latest release. Then either upload it under Admin → Extensions, or put it in your heavy image's build/extensions/ directory and run docker compose restart web. Extensions require the :heavy panel image (or a dev environment); see the Calagopus docs.

No configuration is needed. The Mods page appears in every server's sidebar. To hide it for non-Minecraft eggs, use the egg configuration's route order.

The server is inspected in this order, and the first source that finds a value wins:

1. Server log: logs/latest.log, e.g. Loading Minecraft 1.21.1 with Fabric Loader, Forge and NeoForge launch arguments, Starting minecraft server version ….
2. Server files: loader libraries (libraries/net/fabricmc, net/minecraftforge/forge, net/neoforged, org/quiltmc), launcher jars and versions/<version>.
3. Startup variables: e.g. MINECRAFT_VERSION, MC_VERSION, FORGE_VERSION, NEOFORGE_VERSION.
4. Egg: the egg, nest, startup command or Docker image name mentions a loader.

Start the server once if something isn't detected. You can always pick the loader and version yourself in the Install Mod modal.

The extension uses the panel's existing file permissions:

Installs, renames and deletions go through the panel's own file endpoints, so they respect subuser ignored files and appear in the server's activity log.

This repository uses the extension's development layout (Cargo.toml, Metadata.toml, src/, frontend/). Symlink it into a panel checkout as backend-extensions/dev_caloptreyx_modinstaller, then run from the panel root:

SQLX_OFFLINE=true cargo clippy -p dev_caloptreyx_modinstaller --all-targets
SQLX_OFFLINE=true cargo test -p dev_caloptreyx_modinstaller
cd frontend && ./node_modules/.bin/tsc && ./node_modules/.bin/biome check extensions/dev_caloptreyx_modinstaller/src && cd ..
SQLX_OFFLINE=true panel-rs extensions export dev.caloptreyx.modinstaller   # -> exported-extensions/

• Backend (src/): GET /api/client/servers/{server}/mod-installer/environment (detection) and GET /api/client/servers/{server}/mod-installer/mods (the mods/ listing with SHA-1 fingerprints). Detection is the pure, unit-tested src/detect.rs.
• Frontend (frontend/src/): talks to the Modrinth API directly from the browser. Installs use the panel's file pull endpoint; enabling, disabling and deleting use its rename and delete endpoints.

MIT