JetBrains/Mellum2.1-12B-A2.5B-Thinking-GGUF
text-generation model by JetBrains
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Model card & documentation
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This repository contains GGUF builds of JetBrains/Mellum2.1-12B-A2.5B-Thinking in every quantization we publish, ready to run with llama.cpp, Ollama, LM Studio, and other GGUF-compatible runtimes. Each variant is one file; download the one you need. The repository also ships the model's multi-token prediction (MTP) head for speculative decoding in llama.cpp; see Speculative decoding with the MTP head. Mellum2.1 Thinking is a Mixture-of-Experts reasoning model (64 experts, 8 activated per token, 131,072-token context) that emits its chain of thought inside ... blocks before the final answer. For the full model description, evaluation results, and architecture details, see the original model card: JetBrains/Mellum2.1-12B-A2.5B-Thinking. KL divergence and top-token agreement are measured against the BF16 logits on Wikitext-2 (nctx=512); lower KLD / higher agreement means closer to the unquantized model. The server exposes an OpenAI-compatible API on http://localhost:8080/v1: Mellum2.1 Thinking was trained with a multi-token prediction head: one extra transformer block (same attention and MoE…
Read the full model card ↗ · Preview checked 2026-11-01T04:11:31.124Z
Inside the original model card — Document outline
- Mellum2.1 Thinking — GGUF
- Available quantizations
- Download
- Run with llama.cpp
- Speculative decoding with the MTP head
- Run with Ollama
- License
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Documentation belongs to its respective authors. Reported project/model license: apache-2.0. A listing is not a grant of reuse or training rights. Confirm the document’s own terms at the source.
Model overview
JetBrains/Mellum2.1-12B-A2.5B-Thinking-GGUF is a text-generation model repository published by JetBrains on Hugging Face. The source reports the gguf library.
This page summarizes Hub metadata. For intended use, training data, evaluation results and limitations, consult the original model card.
Model facts
- Task
- text-generation
- Library
- gguf
- Recent downloads (30 days)
- 122,022
- Cumulative likes
- 123
- Hugging Face trending score
- 55
- Reported safetensors parameters
- Not reported
- Architecture
- Not reported
- License
- apache-2.0
- Access
- Not gated by Hugging Face
- Created
- 2026-10-07T18:43:52.000Z
- Last modified
- 2026-10-07T18:52:45.000Z
Compatibility and lineage
Reported languages: en
Reported base models: JetBrains/Mellum2.1-12B-A2.5B-Thinking
Parameter count is not a RAM/VRAM requirement. Check precision, quantization, context length and runtime compatibility in the model card; no hardware or API-cost claim is inferred here.
Use and evaluate
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Source and freshness
Source: Hugging Face Hub. Metadata observed 2026-10-19T06:42:12.963Z. Daily imports are snapshots, not real-time monitoring.
Popularity and source listings do not establish security, suitability, licensing rights or benchmark performance.