BitMamba-2-1B is a scalable, hybrid architecture that integrates 1.58-bit ternary quantization (BitNet) into the Mamba-2 state space model framework. Trained from scratch on 150B tokens of high-quality data, it demonstrates that ternary SSMs follow predictable scaling laws, achieving competitive reasoning capabilities with a drastically reduced memory footprint.
ARM NEON Port — Cross-Platform CPU Inference
An ARM NEON port of the BitMamba-2 inference engine has been developed by Aquantic Research, enabling native inference on Apple Silicon (M1/M2/M3/M4) and ARM-based processors.
Model
Hardware
Speed
Latency/token
RAM
BitMamba-2 1B
Intel Core i3-12100F (AVX2)
~53 tok/s
—
621 MB
BitMamba-2 1B
Apple M1 (ARM NEON)
27.9 tok/s
35.9 ms
614 MB
Key finding: Speed is perfectly constant regardless of sequence length (50, 200, or more tokens). This experimentally validates the O(1) memory property of SSM architectures — unlike Transformers whose memory grows with sequence length.
Comparison with Transformer baselines (same hardware)
Type
Model
Weights
Quant
tok/s
Hardware
SSM
BitMamba-2 1B
614 MB
1.58-bit
27.9
Apple M1
Transformer
TinyLlama 1.1B
638 MB
Q4_K_M
~30-40
Apple M1
Transformer
Llama-7B
3.8 GB
Q4
~15
Apple M1
Cloud GPU
Claude 3.5 Haiku
—
—
61
GPU cloud
At comparable weight sizes (~600 MB), the SSM achieves throughput competitive with quantized Transformers, but with constant memory (no KV cache growth) and 1.58-bit compression (vs. 4-bit for Transformers).
ARM NEON Port Resources
Code: rasata/bitmamba.cpp — ARM NEON fork with cross-platform dispatch (x86 AVX2 + ARM NEON)
Preprint: "State Space Models as CPU-Native Neural Network Architectures: Experimental Evidence from ARM NEON Inference with 1.58-bit Quantized Mamba" — Gabriel Zo-Hasina Rasatavohary, Aquantic Research, March 2026. To be published on engrXiv (DOI pending).
1# Clone the ARM NEON fork2git clone https://github.com/rasata/bitmamba.cpp
3cd bitmamba.cpp
45# Build (macOS Apple Silicon)6brew install libomp
7cmake -B build && cmake --build build
89# Download weights from this repo10wget https://huggingface.co/rasatavohary/BitMamba-2-1B/resolve/main/bitmamba_cpp/bitmamba_1b.bin
1112# Run inference13cd build &&cp../tokenizer.bin .14./bitmamba ../bitmamba_1b.bin "The future of AI is" tokenizer 0.71.10.050.940200