apertus-mini-mlx

Experimental MLX-backed Ollama builds of the Apertus v1.1 Mini Instruct models, available in 0.5B, 1.5B, and 4B parameter sizes.

These models require a custom Ollama build with experimental MLX safetensors support and ApertusForCausalLM support. They will not run on the regular public Ollama app/build.

If you are ready to install a custom Ollama build, visit https://pd95.github.io/Ollama/.

Known limitation

The currently published Mini artifacts can produce nonsensical chat responses and may disregard information supplied earlier in a conversation. This affects the 0.5B, 1.5B, and 4B BF16 and NVFP4 variants. They are not recommended for conversational use while the issue is investigated. Prompt rendering appears correct; the cause may be upstream Mini model quality or a Mini-specific MLX runtime parity issue. Apertus 1.0 8B is not affected.

Tags

• pd95/apertus-mini-mlx:0.5b, :1.5b, and :4b — current NVFP4 defaults; see the known limitation above
• pd95/apertus-mini-mlx:<size>-nvfp4 — explicit NVFP4 artifacts
• pd95/apertus-mini-mlx:<size>-bf16 — explicit BF16 artifacts
• pd95/apertus-mini-mlx:<size>-<quantization>-v0.32.15-r2 — immutable release tags

The six initial immutable artifacts are 0.5b-bf16-v0.32.15-r2, 0.5b-nvfp4-v0.32.15-r2, 1.5b-bf16-v0.32.15-r2, 1.5b-nvfp4-v0.32.15-r2, 4b-bf16-v0.32.15-r2, and 4b-nvfp4-v0.32.15-r2.

Source

These models are experimental Ollama/MLX conversions of Apertus v1.1 Mini Instruct checkpoints:

• https://huggingface.co/swiss-ai/Apertus-v1.1-0.5B-Instruct
• https://huggingface.co/swiss-ai/Apertus-v1.1-1.5B-Instruct
• https://huggingface.co/swiss-ai/Apertus-v1.1-4B-Instruct

Apertus is released by the Swiss AI Initiative / Swiss National AI Institute.

License and Use Policy

The upstream Apertus v1.1 Mini checkpoints are released under the Apache License 2.0. Each published artifact includes an Apache-2.0 license layer.

This repository republishes converted or quantized MLX/Ollama artifacts. It does not change the upstream license or usage terms. Please review the upstream model card and license before use or redistribution.

Notes

• Architecture: Apertus v1.1 Mini Instruct
• Quantizations: BF16 and NVFP4
• Stored capabilities: text, tools, thinking; these do not establish conversational reliability
• Minimum supported custom MLX preview: v0.32.6
• Validated custom MLX preview range: v0.32.6 through v0.32.15-r2
• Runtime: experimental Ollama MLX runner

These models are retained for experimental investigation of the Apertus MLX path in Ollama. They are not supported by the regular public Ollama app/build.