Overview
Deltafin is a single compiled Rust binary that runs the complete, unmodified Kimi K3 — 2.8 trillion parameters in a Mixture-of-Experts layout — on one consumer machine. The design choice that defines it is refusing to shrink the model: all 16 experts still process every token, so nothing is pruned, distilled or quantized away to make the weights fit. Instead of fitting the model into memory, Deltafin leaves the expert weights on storage and streams each expert in only when the router asks for it, using router tracing and expert prefetch to hide the read latency. Tokenization is native to the binary, so there is no Python at runtime.
The ARGODRIVE build maintained by Argonaut Labs is a fork of gavamedia's original Deltafin, adding the multi-SSD storage work and a published benchmark package. On an M5 Max MacBook Pro with 128 GB of RAM and 1.45 TB of weights spread across four SSDs, it reports steady decode of 1.00 tokens per second on a 512-token answer and 1.13 tok/s on a 128-token one. Drive count is the main lever: one drive reaches roughly 52% of the four-drive speed, two 73% and three 90%. An optional smaller draft model called DSpark speeds up decoding, with K3 itself verifying every token DSpark proposes, so the output is unchanged.
Deltafin runs on macOS arm64, Linux x86-64 and Linux aarch64, with MPS/Metal, CUDA and CPU acceleration paths. Besides an interactive chat mode it exposes an OpenAI-compatible REST server for chat completions and raw completions, so local coding agents and chat clients can point at it directly. The project is independent of Moonshot AI; Deltafin's own code is MIT-licensed while the K3 weights keep their upstream terms.
What it does
- Runs the full unmodified 2.8T-parameter Kimi K3 with all 16 experts active per token — no pruning, distillation or quality trade to fit the machine
- Streams expert weights on demand from one or more SSDs, with router tracing and expert prefetch used to hide storage latency
- Measured multi-drive scaling: one SSD gives about 52% of four-drive speed, two 73% and three 90%
- Optional DSpark draft model (about 4.49 GiB when admitted at runtime) accelerates decoding, with K3 verifying every proposed token
- Single compiled Rust binary with C-ABI providers and native tokenization — no Python needed at runtime
- OpenAI-compatible REST server (`deltafin serve`) for chat completions and raw completions, so local agents and chat UIs can connect
- MPS/Metal, CUDA and CPU acceleration paths across macOS arm64, Linux x86-64 and Linux aarch64
Getting started
You need a supported platform (macOS arm64, Linux x86-64 or Linux aarch64), a Rust toolchain to build, and a lot of disk: about 1.7 TB for the full model download, or 215 GB minimum in streaming mode, plus 6.635 GiB for DSpark and an optional 4.337 GiB for Qwen.
Build the binary
Clone the repository and build a release binary with Cargo.
git clone https://github.com/gavamedia/deltafin.git
cd deltafin
cargo build --locked --releaseFetch the model
`setup --full` downloads the complete 1.7 TB model. Use `--stream` for the smaller streaming footprint, and `--include-qwen` if you also want the optional Qwen weights.
./target/release/deltafin setup --fullRun a prompt or start chatting
`run` takes either an interactive `--chat` session or a one-shot `--prompt`. `--max-new` caps generated tokens and `--stats` prints timing.
./target/release/deltafin run --chat
./target/release/deltafin run --prompt "Your question here" --statsServe an OpenAI-compatible endpoint
`serve` exposes chat and raw completions over HTTP so local coding agents and chat clients can use the model. Only one generation runs at a time.
./target/release/deltafin serve --host 127.0.0.1 --port 8000Commands and code are distilled from the project's own documentation — always check the official repo for the latest.
When to use it
- Run a frontier-scale open-weight model privately on hardware you own instead of renting it behind an API
- Point a local coding agent or chat client at a 2.8T model through an OpenAI-compatible endpoint on localhost
- Trade throughput for capability on batch or overnight work, where roughly 1 token per second from Kimi K3 is acceptable
- Study how far SSD bandwidth and drive striping can substitute for RAM when serving a very large Mixture-of-Experts model
How Deltafin compares
Deltafin alongside other open-source local runtimes tools AI/TLDR tracks, ranked by GitHub stars.
| Tool | Stars | What it does |
|---|---|---|
| Ollama | ★ 180k | A developer-friendly tool that downloads and runs local LLMs from the terminal with a built-in OpenAI-compatible API. |
| llama.cpp | ★ 128k | A C/C++ inference engine that runs LLMs in the GGUF format on CPUs, Apple Silicon, and GPUs with low memory use. |
| GPT4All | ★ 77.4k | GPT4All is a free desktop app and Python client that runs large language models locally on your own computer, with no API calls or GPU required. |
| LocalAI | ★ 49k | A self-hosted server that exposes an OpenAI-compatible API for running text, vision, voice, and image models on local hardware. |
| Jan | ★ 44.4k | An open-source desktop app that runs LLMs fully offline as a ChatGPT-style assistant on your own computer. |
| AirLLM | ★ 33.9k | A Python inference library that keeps only one transformer layer on the GPU at a time, so a 70B model runs on a single 4GB card and a 671B MoE model on about 12GB, without quantization. |
| Colibrì | ★ 27.1k | A pure-C inference engine that keeps a Mixture-of-Experts model's dense trunk resident in RAM and streams its routed experts from disk, so 744B-2.8T models run on consumer hardware. |
| Deltafin | — | A Rust runtime that streams Kimi K3's expert weights from SSDs so the full 2.8T model runs on one machine |