Skip to content

Achievements Optimizer

Improved achievement performance

FabricNeoForgeForge
Loaders
FabricNeoForgeForge
Downloads on Modrinth
1.3M
Followers on Modrinth
189
versions
31
Updated
June 8, 2026Jun 8
Published
in 2023

At a glance

Runs on Fabric, NeoForge and Forge
For Minecraft 1.21.9–1.21.11, 26.1.2 …
Needed on the server; optional in the game
Latest version — 2.1.2 from June 8, 2026
Requires Architectury API
License MIT — free
Where it's needed
In gameoptionalOn serverrequired

Needed on the server; optional in the game

Game versions1.21.4, 1.21.9–1.21.11, 26.1.2 …

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.

⚙️** Key Optimizations**

  • Early tick skipping — heavy slot calculations (empty/occupied/full) are skipped early, preventing extra work per event.
  • Instant empty stack discard — with ignoreEmptyStacks enabled, empty stacks are removed immediately without scanning the entire inventory.
  • Fast multi-item matching — single-pass inventory check using boolean[] flags with early exit. No allocations, noticeably faster on large inventories or long condition lists.
  • Early slot filtering — slots.matches(full, empty, occupied) is evaluated first, avoiding deeper checks when slots don’t match.
  • Preserved fast path for single targets — when items.size() == 1, the comparison is done directly on the changed slot without a full inventory pass.

🚀 Result

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!

FAQ

How to install Achievements Optimizer?

Install Fabric for your Minecraft version, download Achievements Optimizer for the same version and loader, put the file into the mods folder and launch the game with the loader profile.

Which Minecraft versions does Achievements Optimizer support?

Achievements Optimizer has builds for Minecraft 1.21–1.21.1, 1.21.4, 1.21.9–1.21.11, 26.1.2 ….

Is Achievements Optimizer needed on the server?

Needed on the server; optional in the game

License and source
MIT Licensefree to use and share with credit to the author
Original — Modrinth↗Files unchanged, verified with SHA-512Is this your mod? For rights holders

The site uses cookies: the necessary ones for sign-in and the theme, plus the Yandex Metrica and LiveInternet visit counters — they show us how the site is used. We have no advertising cookies. More