InstaPack

Server resource packs and resource reloads that take seconds instead of minutes.

What it does

• Fast resource reload. Vanilla scans every file of every zip pack each time a mod lists resources. InstaPack indexes the zip once. On a 90 mod client this took the reload from 80 s to 4 s.
• No reload when nothing changed. Rejoining a server, or switching servers behind a proxy with the same pack, skips the reload entirely.
• Partial reload. If a pack only changes languages, sounds, fonts or splash texts, only those parts are reloaded, without a loading screen.
• Shared pack cache. Packs are cached by hash, so the same pack from another server or with a new UUID is never downloaded twice.
• Delta downloads (with the server plugin). When a server updates its pack, you download only the files that changed.

Server plugin (optional)

Paper and Velocity. Hosts the pack with a built-in web server, sends it to players on join, and pushes updates as soon as files change. Players with the mod get only changed files. Players without it get a normal zip, nothing breaks.

Put the pack, unzipped, into plugins/InstaPack/pack/, or point source at a zip made by another plugin. A zip is sent to vanilla clients byte for byte.

Config

config/instapack.properties on the client. Every feature can be turned off.

Compatibility

Client only on the mod side. Fabric and NeoForge, Minecraft 1.21 to 26.3. Works on any server, the plugin is not required.