JujutsuCraft Fix

A server performance addon for JujutsuCraft. Same moves, same mechanics, same visuals: the server just does less work to run them.

What it does

JujutsuCraft runs a lot of work on every tick: thousands of text commands to spawn particles and place blocks, repeated data lookups, and block-by-block scans for domains and destruction. This addon makes that work cheaper without changing what it does:

• Internal commands (particles, effects, block placement, entity data) are executed directly instead of being parsed by Minecraft's command system every time.
• Particle bursts are sent to players in grouped network packets.
• Domain and destruction procedures stop re-reading the same blocks, chunks and values.
• Repeated lookups (identifiers, entity data, player variables) are cached or done once.

Results

Measured by replaying all 196 moves of every JujutsuCraft mob, 3 times each, with and without the addon:

Every move behaves the same with and without the addon: same outcome, same blocks destroyed. Automated in-game tests also compare each optimized command with Minecraft's own result.

What to expect: the gain shows on busy servers, with many players and fights at once. In singleplayer the server is usually far from its limit, so you won't notice a difference.

This addon does not improve FPS. It only reduces server-side work (TPS / MSPT).

Configuration

Every optimization can be turned off in config/jujutsucraft_fix-common.toml.

Server operators can compare live, without restarting:

• /jjfix optimizations off: all optimizations off (original JujutsuCraft)
• /jjfix optimizations on: all optimizations on
• /jjfix optimizations config: back to the config file
• /jjfix optimizations: show the state of each optimization

Compatibility

Not tested with other JujutsuCraft addons yet. It should work alongside most mods, but an addon that modifies the same parts of JujutsuCraft's code could conflict. If you hit a crash or odd behavior, please report it with your mod list.