
Modrinth · Minecraft mod
Alfheim
Alfheim is a lighting engine replacement for Minecraft, optimized for performance and fixing many bugs
Quick answer
Which Alfheim release should I use?
Alfheim 1.6 targets 1.12.2 with Forge. Installation on the client is optional. Installation on the dedicated server is optional. All 2 required mods have matching files.
Where it goes
Is Alfheim required on the client, server, or both?
Installation on the client is optional. Installation on the dedicated server is optional.
The source marks this as usable on both the client and server.
What else does Alfheim 1.6 need?
1.6. Change the file and its required mods may change too.
Install Red Core, MixinBooter first. We found matching files for this game-version and loader setup.
We only count dependency files that match this setup. A file for another loader does not fill the gap.
Before you install it
Add Alfheim without breaking your instance.
Built for Alfheim 1.6. Pick another file and the loader, install side or required mods may change.
- 01
Stick to this file
Use 1.6. It targets 1.12.2 with Forge; another release may have different loader, side or dependency requirements.
- 02
Bring the mods it needs
Install Red Core, MixinBooter first. We found matching files for this game-version and loader setup.
- 03
Put it on the correct side
Installation on the client is optional. Installation on the dedicated server is optional.
- 04
Pick the file you checked
Use the “Get this file” button beside 1.6. It opens that exact file at the source.
About this project
What does Alfheim add?
Alfheim
Alfheim is a fork (or a rewrite depending on your views on the ship of theseus) of Hesperus which is a fork of Phosphor
What benefit does this have over Phosphor/Hesperus?
Alfheim aims to be compatible in all scenarios, and if for any reasons a something is fundamentally incompatible, a warning will tell you what is happening instead of crashing with hardly any information.
Alfheim also has a lot of optimizations of all sizes over Phosphor/Hesperus it uses slightly less memory overall.
Alfheim also improves client side performance unlike Phosphor/Hesperus, by reducing by lighting related block updates by a factor of 27.
To improve client side performance, Alfheim also limits how much lighting updates are performed each frame.
In addition, Phosphor/Hesperus unnecessarily forces lights to be updates before each frame which Alfheim doesn't.
Alfheim also fixes more vanilla lighting issues than Phosphor/Hesperus, here is a list of all fixes and where they come from:
Fixed in Alfheim:
Why not just PR to Hesperus?
Fair question, the reason is simple, Alfheim compared to Hesperus isn't just a fork to fix bugs, it is my continuation of it.
And as seen in the past, my continuations of mods aren't just modifying some things, they are pretty invasive and basically change everything internally.
It wasn't this way at first, I wanted to PR some stuff to Hesperus but after doing parts of it, it became clear that it had grown bigger than a PR.
So then I decided to do Alfheim, for now it includes optimizations, bug fixes and compatibility fixes, but later down the line I have more plans.
Want to have your own mod or support me?
If you're looking for a mod but don't have the development skills or time, consider commissioning me!
My commissions are currently open and I would be happy to create a custom mod to fit your needs as long as you provide assets.
You can also support me on a monthly basis by becoming a member.
To thank you will have the possibility to access exclusive post and messages, Discord channel for WIP content, and even access to unreleased Prototypes or WIP Projects.
You can also buy me a hot chocolate.
Project description from Modrinth.
Pick your setup
Alfheim by Minecraft version and loader
Choose the version and loader you play, then open the matching release.
1.12.2
1 loader buildCheck the dependencies, then try the file in a copied instance before changing a world you care about.
Recent files
Alfheim versions and loaders
1.6
Alfheim-1.6.jar
23 Jun 2025
1.5
Alfheim-1.5.jar
11 Feb 2025
1.4
Alfheim-1.4.jar
21 Aug 2024
1.3
Alfheim-1.3.jar
28 Mar 2024
1.2
Alfheim-1.2.jar
11 Dec 2023
1.1.1
Alfheim-1.1.1.jar
19 Nov 2023
1.1
Alfheim-1.1.jar
17 Nov 2023
1.0.2
Alfheim-1.0.2.jar
12 Sept 2023
1.0.1
Alfheim-1.0.1.jar
8 Sept 2023
1.0
Alfheim-1.0.jar
6 Sept 2023
Looking for an older file? The official Modrinth project page is in Resources.