About Soup
Soup is an open-source toolkit for LLM post-training on local hardware, built by MePlay, Inc..
Fine-tuning has a hardware floor that has very little to do with the work itself. A model whose weights do not fit on your card cannot be trained on it, so the answer has always been to rent a bigger one. Soup's core technique, layer streaming, moves that floor.
How it works
The frozen base is never loaded into VRAM as a whole. It is rewritten into one shard per decoder layer, held in CPU RAM or on NVMe, and copied one layer at a time into a small pool of pre-allocated VRAM buffers on a dedicated CUDA stream, so the load of the next layer overlaps the compute of the current one. Only the LoRA adapters stay resident, which bounds peak VRAM by a single layer instead of by the whole model.
Quantizing that streamed base to NF4 shrinks the store about fourfold, and that is what brings an 8B model within reach of a card that cannot hold a quarter of it: Llama-3.1-8B-Instruct fine-tunes on a 4 GB RTX 3050 Laptop at 119.6 tok/s with a peak of 3.32 GB. That rate was measured before the v0.73.0 correctness repair and has not been re-run on that card since.
Ten architectures stream, covering Llama, Qwen, Qwen4-Exp, Mistral, Gemma and Phi. The original nine are verified bit-exact against the same checkpoint loaded resident, under both bf16 and NF4; the newest additions carry weaker evidence and the docs say which. That check is the load-bearing one, because a streamed run that has quietly severed its autograd graph still produces a falling loss curve and looks healthy.
For a long time that check could only run on toy models, because comparing a streamed run against a resident one needs a card big enough to hold the resident one, and a 4 GB card never is. In August 2026 three borrowed days on an 8x H100 box closed that gap. The streamed forward pass proved exact against a real resident reference from 8B up to 72B, and the same exercise found a gradient defect above a certain layer size that three releases of passing tests had missed.
Layer streaming ships BETA. Every number behind it is published as a measurement record, including the ones that were measured and then discarded, and including the defects the measuring turned up.
Company
Soup is developed and maintained by MePlay, Inc.. The company is the entity behind this site, the soup-cli package on PyPI and the repository on GitHub.
- Legal name
- MePlay, Inc.
- Incorporated
- Delaware, United States, October 1, 2025
- Registered address
- 1111b South Governors Avenue, STE 40549, Dover, DE 19904
- Contact
- team@trysoup.dev
- Product
- soup-cli (v0.75.0), released under the Apache-2.0 license
Soup is free and stays that way. There is no paid tier and nothing held back for a commercial edition. If you want to help, starring the repo costs nothing and helps most.