Chlorine
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Chlorine was made with Claude, Anthropic's AI, working through Claude Code. I chose what to build, tested it, and decided what shipped. This page says which parts were whose, and how much of it is still unproven.
The mod, its settings screen, this website and its copy were written by AI. The project's README also lists ChatGPT Codex, GitHub Copilot and Nemotron 3.5 super VL as tools used along the way. The chat log below is the Claude Code session from 1.0.5 onward, written by Claude Opus 5.5 and Claude Sonnet 5.5.
I set the direction, picked which ideas to build, and sent the screenshots. I tested the builds in the game on a Ryzen 5 5500 with a Radeon RX 6500 XT, and decided what to keep, rename and release. I attach each jar and publish each release myself. Claude can't see the game, so tuning followed what I reported.
The newest changes (1.0.6 to 1.0.8) have no controlled frame-time benchmark. The numbers on the Benchmarks page are sampled readings from recordings on one PC. The demos on this site illustrate the ideas, they are not measurements.
Checked and not checked
These are the claims I can stand behind today, and the ones I can't yet.
Releases are built from a clean state. The 1.0.7 Sodium changes were run in a real client with Sodium 0.9.2, and the patched code was inspected to confirm the hooks landed.
Recent testing was on one PC and one version, Minecraft 26.3 with Sodium 0.9.2. Other hardware, other versions and large modpacks have not been tested.
The frame smoothing and Sodium changes are meant to soften hitches. No capture tool such as CapFrameX has been used to measure 1% lows before and after, so no gain is claimed.
It compiles and ships in 1.0.8, but it has not been played over long sessions or benchmarked. It can't replace Java's garbage collector, which your launcher's JVM flags control.
They target Sodium's internal code, so a Sodium update can make them stop applying. They are written to skip quietly rather than crash, but that means a future update could silently remove their effect.
Where it comes from
Chlorine is not a fork. It is a separate project that leans on these mods and tools, and it is not affiliated with any of them.
It runs on Fabric Loader and Fabric API, with Mojang's official mappings, and uses Mixin hooks to change game behavior.
The in-game settings screen is built with Cloth Config, which is required. Mod Menu is optional and only adds a Config button to the mod list.
From 1.0.3 on, Chlorine requires Sodium 0.9.2 or newer and hooks into its chunk renderer. Claude read the compiled Sodium jar to find the hook points. No Sodium source code is copied into this repository, and Sodium is not bundled: you install it yourself. Sodium is licensed under PolyForm Shield 1.0.0 by CaffeineMC.
It is designed to coexist with Lithium, FerriteCore, EntityCulling, ImmediatelyFast and Iris. None of them is required, and none of their code is in Chlorine.
Chlorine is All Rights Reserved (ARR), with the copyright held by Pavan Nemani. It is not open source: the repository's LICENSE file says what you may and may not do. The 0.1.x public betas are the exception: they were released under MIT, and those releases keep it. Chlorine is not affiliated with Mojang, Microsoft, Anthropic, CaffeineMC or the mods named above.
The receipts
From the first message of the Claude Code session to the request for this page. Only what was said in the chat is shown. Tool use is left out, and file paths, local addresses, emails and keys are masked. It reads like a messaging app, but you can't reply.
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Not affiliated with Mojang, Microsoft, CaffeineMC or Anthropic.