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CurseForge · Minecraft mod
AttachmentsAPI
Allows registration of saved, synched custom data on any entity using a simple event, attachments can also be setup to allow changing from only serverside or only clientside but by default can be set by client or server
Choose a version Pick your version below, then grab the matching file.
Quick answer
Which AttachmentsAPI release should I use?
Latest stable file NeoForge 1.21.8
Game version 1.21.8
Loader NeoForge
AttachmentsAPI NeoForge 1.21.8 targets 1.21.8 with NeoForge. The project page does not say whether this file belongs on the client, dedicated server, or both. No extra mods listed for this file.
Where it goes
Is AttachmentsAPI required on the client, server, or both?
The project page does not say whether this file belongs on the client, dedicated server, or both.
Client Source doesn’t say
Dedicated server Source doesn’t say
Loader for this release NeoForge
Required install it here Optional supported, not mandatory Not supported do not install here Source doesn’t say do not assume
The source does not explicitly classify this release as client-only or server-only.
What else does AttachmentsAPI NeoForge 1.21.8 need?
NeoForge 1.21.8. Change the file and its required mods may change too.
This file does not list any required mods. Do not add a library just because a different file uses it.
This file does not list any required or optional mods.
Before you install it
Add AttachmentsAPI without breaking your instance.
Built for AttachmentsAPI NeoForge 1.21.8. Pick another file and the loader, install side or required mods may change.
- 01
Stick to this file
Use NeoForge 1.21.8. It targets 1.21.8 with NeoForge; another release may have different loader, side or dependency requirements.
- 02
Bring the mods it needs
This file does not list any required mods. Do not add a library just because a different file uses it.
- 03
Put it on the correct side
The project page does not say whether this file belongs on the client, dedicated server, or both.
- 04
Pick the file you checked
Use the “Get this file” button beside NeoForge 1.21.8. It opens that exact file at the source.
About this project
What does AttachmentsAPI add?
This is an API meant to be used by other mods and is not a standalone mod, its the second API I've ever made and its intended to allow easy registration of custom data for entities that are both saved and synched while also adding events for pre/post updating of the data and also an event for when a value changes (with support to cancel or change the new value)
Any API I make is mainly meant for usage in something else I'm working on or in general for my mods, however they are available for public use if a user desires
If you would like to use this API then you can find the relevant information below;
- Event used to register custom data [RegisterAttachmentsEvent]
- Event used to add registration helpers [RegisterAttachmentTypesEvent] (Optional Command Support)
- Event used to trigger things on data update [UpdateAttachmentEvent]
- Event used to change or prevent data changes [ChangeAttachmentEvent]
- Utility class used to interact with custom data easily [Attachments]
Project description from CurseForge.
Pick your setup
AttachmentsAPI by Minecraft version and loader
Choose the version and loader you play, then open the matching release.
Check the dependencies, then try the file in a copied instance before changing a world you care about.
Recent files
AttachmentsAPI versions and loaders
NeoForge 1.21.8
attachments_api-1.0.1-neoforge-1.21.8.jar
30 Sept 2026
Client Source doesn’t say Server Source doesn’t say Dependencies No extras listed Listed on Release listing
Check the 1.21.8 · NeoForge setup 1.21.8NeoForge release
Looking for an older file? The official CurseForge project page is in Resources.