PrismML shrinks Bonsai 2 9B model to 2GB, says it can generate 34 tokens per second on iPhone 18 Pro Max

PrismML, a U.S. AI company, has added three new models to its Bonsai 2 family: 2B, 4B, and 9B, all built on Alibaba’s Qwen3.5. The team said it constrained the main weights of the language models to just three values, -1, 0, and +1, reducing the model files to 0.43GB, 0.95GB, and 2GB, or about one-ninth the size of the original 16-bit weights. The company said the new models still support reasoning, image understanding, and tool use, with a focus on local agents running on phones and personal computers. According to PrismML, the 9B model can generate up to 34 tokens per second on an iPhone 18 Pro Max, while the 2B version reaches 120 tokens per second. In the company’s official tests, the 9B model came close to the original same-sized Qwen3.5 in coding and instruction-following tasks, but showed a wider gap on more complex workloads. PrismML has released the weights for all three models under the Apache 2.0 license.