A sovereign, open-weights agentic coding model by Dappit Labs. 35B
Mixture-of-Experts (≈3B active), built by layering Claude Fable-5 / Opus-4.8 agentic tool-use
behavior onto an abliterated, Opus-4.7-reasoning-distilled Qwen3.6-35B-A3B.
⚠️ Numbers are from our own harness (see Evaluation); nothing here is a claim against official
leaderboards.
TL;DR
fable-coder is a chained distill + behavioral fine-tune for Claude-Code-style agentic coding:
Qwen3.6-35B-A3B (Apache-2.0)
└─ Opus-4.7 reasoning distill (lordx64/…-Reasoning-Distilled)
└─ abliteration (huihui-ai/…-abliterated) ← our base
└─ LoRA fine-tune, agentic rounds r3→r4→r6 ← this model (r6)
Reasons natively in Qwen <think> chains (inherited from the Opus-4.7 prior; intact — verified).
Acts like a coding agent — emits tool calls and edits when driven inside an agent harness
(the Fable-5/Opus-4.8 agentic SFT).
Runs on a 32GB GPU at Q4/Q5 (a 24GB card works at short context), up to Q8 (~38GB) on a 48GB+ GPU or 64GB Mac. CPU/Metal too. (Realistic size-vs-hardware table below.)
r6 is the released round; r4 (the prior round) is documented alongside for provenance.
Honest scope
This is not a single-teacher distillation from scratch, and it does not aim to exceed its
teachers. It is a behavioral graft: the reasoning comes from the Opus-4.7 distill in the base; our
LoRA rounds add agentic coding behavior distilled from verified Claude Fable-5 / Opus-4.8 Claude
Code sessions. Evaluate and use it accordingly:
Reasoning / math / knowledge: driven by the underlying Opus-4.7 distill. fable-coder ~matches
it; it does not beat it.
Agentic coding (edit files, run tests, iterate): this is where our training adds value over the
vanilla base — see MBPP and the r4→r6 delta.
Chat / assistant: works, but persona may drift toward a Claude voice (stacked Anthropic-style SFT).
bf16; train_on_responses_only; MoE router aux loss on
Seq length
4096
Final round (r6)
fresh continuation on the r4 adapter, LR 2e-5, 1 epoch (126 steps)
r6 data
1,007 agentic-only windows — verified Claude Code coding sessions (our own generation + community Fable-5 traces + Glint corpus + swarm-salvage). Instruction-pair data from earlier rounds was removed for this round.
Data hygiene
rejection-sampled (kept only sessions whose tests/build passed); zero-overlap hash-assert vs prior rounds; secrets/PII scrubbed
Lineage note (a documented lesson): an intermediate round (r5) that restarted from base with a
filtered corpus regressed hard (HumanEval 90.9 → 71.3). The fix — and the method used for r6 — is
strict adapter continuation plus an agentic-only final corpus. r6 recovered and improved.
Evaluation
Methodology & honesty. All numbers below are our own harness, q8_0 GGUF, native thinking
(temp 0.6 / top-p 0.95), single-sample pass@1, run locally. They are not directly comparable to
official leaderboards (different precision, harness, and prompting). AIME uses a 16k-token
budget so long reasoning chains don't truncate.
Benchmark
r6 (this model)
r4 (prior round)
Base (huihui)
HumanEval (pass@1)
90.2
90.9
90.2
MBPP (pass@1)
78.2
76.2
73.0
GSM8K
94.7
95.0
—
MATH-500
88.2
89.4
—
AIME 24+25 (16k)
73.3
71.7
—
MMLU-Pro
79.8
77.2
—
Read: r6 preserves the base's reasoning (GSM8K/MATH/MMLU-Pro/AIME all healthy) while improving the
metric closest to its job — MBPP +5.2 over base, +2.0 over r4 — with no regression on any
axis versus r4. Reasoning is preserved; coding — the model's actual job — improves.
🚧 Pending: SWE-bench Lite (agentic harness) is the key remaining test — it measures the actual
coding-agent axis these benchmarks can't. Numbers will be added when verified.
Quantizations
Produced locally with llama.cpp from the bf16 master (llama-quantize):
Quant
Weights
GPU / Mac (with room for context)
Q8_0
38GB
48GB+ GPU · 64GB Mac — near-lossless
Q6_K
29GB
40GB+ GPU · 48GB Mac
Q5_K_M
25GB
32GB GPU
Q4_K_M
22GB
32GB GPU (or a 24GB card at short context)
Sizes are the weights only — budget headroom on top for the KV cache + compute buffers.
The good news: this model's KV cache is unusually small (only 2 KV heads), so long context is cheap —
~2.7GB at 32k, ~11GB at 128k, ~21GB at the full native 256k. That's why it's comfortable on
modest hardware despite being a 35B.
Pre-made GGUF quants (Q4–Q8) → GGUF repo, or ollama run achillessafehavencalls/fable-coder. The full-precision bf16 weights are in this repo — or quantize your own levels (F16, IQ4_XS, etc.) with llama.cpp.
Or serve the GGUFs with llama.cpp / LM Studio / vLLM. Thinking is native — the Qwen template opens <think>
by default; the server returns reasoning in reasoning_content and the answer in content. For
agentic use, run inside a harness that supplies a tool-use system prompt + tool registry (treat it
like Claude Code). Note: tool-name binding is loose at this data scale — downstream tool routers
should normalize invented names (e.g. read_file → Read).
Limitations
Uncensored / abliterated base. Refusals are largely removed. You own compliance and safety for
your use case. (See below.)
Distill, not teacher-surpassing. Won't beat the Opus-4.7 prior on pure reasoning.
Narrow agentic distribution. Training sessions skew web/app/game/web3 coding; out-of-distribution
agent tasks are hit-or-miss.
Our-harness numbers. Not official-leaderboard comparable; SWE-bench pending.
Tool-name vocabulary doesn't bind to a fixed schema — normalize downstream.
License & Responsible Use
Released under Apache-2.0, consistent with the Qwen3.6-35B-A3B base and the Opus-4.7 distill it
builds on (both Apache-2.0). We treat the model weights as an independent artifact, not a derivative
work of the training data.
Provenance disclosures (in the spirit of full transparency):
A portion of the fine-tuning data was distilled from Anthropic Claude Fable-5 / Opus-4.8 model
outputs. Downstream users building products should verify compliance with Anthropic's usage policies
for their specific use case.
Some agentic-trace data was sourced from community corpora, including Glint-Research/Fable-5-traces.
Trace contributors are credited under Attribution.
Responsible use: this is an uncensored (abliterated-base) coding model released for
sovereign/research use. You are responsible for compliance and safety in your deployment. Do not use it
to generate malware, conduct unauthorized intrusion, or carry out other unlawful activity.
Attribution & Acknowledgements
Manifest Network — provided the GPU compute this model was
trained on. This release doesn't happen without them. 🙏
Qwen team — Qwen3.6-35B-A3B (Apache-2.0).
lordx64 — the Opus-4.7 reasoning distill this base builds on.
huihui-ai — the abliterated base.
Anthropic — the Claude Fable-5 / Opus-4.8 teacher behavior distilled here.
Glint-Research, Met4physics, and community trace contributors — corpus sources.
unsloth (MoE+LoRA training) and llama.cpp (GGUF + quantization).
Citation
bibtex
1@misc{fable_coder_35b_2026,
2 title = {fable-coder-35B-A3B: agentic-coding fine-tune of Qwen3.6-35B-A3B (Claude Fable-5/Opus distill)},
3 author = {Dappit Labs},
4 year = {2026},
5 howpublished = {\url{https://huggingface.co/Achilles1089/fable-coder-35B-A3B}},
6}