Achievements Optimizer is a lightweight performance mod that optimizes how item-based achievements and advancements are processed — reducing unnecessary inventory scans and improving overall tick efficiency.
It doesn’t change any gameplay mechanics or logic — only makes achievement checks faster and cleaner under the hood.
ignoreEmptyStacks enabled, empty stacks are removed immediately without scanning the entire inventory.boolean[] flags with early exit. No allocations, noticeably faster on large inventories or long condition lists.slots.matches(full, empty, occupied) is evaluated first, avoiding deeper checks when slots don’t match.items.size() == 1, the comparison is done directly on the changed slot without a full inventory pass.Fewer redundant checks, less memory churn, and faster responses to inventory events.
Particularly beneficial for servers or modpacks with many players and complex advancement triggers.
From version 2.0.0 required Forge Config API Port (only for fabric version).
Feel free to write about all problems and suggestions on my github! Good luck!