logic65/Whittle-Next-27B-A3B

One-line: Post-hoc 27.1B MoE (≈3B active) carved from Qwen3.6-35B-A3B with Qwen3.8-Flash-Next’s 2B-row n-gram memory grafted in — a qwen4_exp (Qwen4-Next) research-preview hybrid that runs on stock llama.cpp, but is explicitly not a finished general-purpose model.

⚠ Research preview, shipped with caveats by the author: “not a finished, general-purpose model… a working starting point”. All numbers are lab-reported (self-run, verified: false, on Q8_0 GGUF via stock llama.cpp; every reply log in eval/). Zero coding/agentic benchmark suite published (no HumanEval/MBPP/LiveCodeBench/Aider/SWE-bench/BFCL/τ-Bench) — HumanEval/MBPP were used only as distillation prompts. No independent third-party eval yet.

Coding benchmarks

BenchmarkScoreSource
HumanEval—not published (used only as distill prompts)
HumanEval+—not published
MBPP—not published (used only as distill prompts)
LiveCodeBench—not published
Aider polyglot—not published
SWE-bench Verified—not published
SWE-bench Multilingual—not published
Code probes (fib / bash / LRU)3/3 correctlab-reported (v3, eval logs in repo)

Agentic / tool-use benchmarks

BenchmarkScoreSource
BFCL—not published
τ-Bench—not published
ToolACE—not published
GAIA—not published

Reasoning (context only)

BenchmarkScoreSource
MMLU / MMLU-Pro—not published
GPQA Diamond—not published
GSM8K (200-Q subset, cap 512, thinking off)86.5% (173/200)lab-reported (v3, full logs in repo)
GSM8K (200-Q subset, cap 1024, thinking off)86.0% (172/200)lab-reported (v3)
GSM8K (200-Q subset, cap 2048, thinking on)86.5% (173/200)lab-reported (v3)
MATH probe (60 train-split L2–4, thinking on)48/60lab-reported (v4.4, vs reader7 43/60)
Long-context reading (6 factual Q on real PR + repo files)6/6 @4k · 5/6 @8k · 4/6 @26k–75klab-reported (v4.3; parent Qwen3.6-35B-A3B: 6/6 everywhere)

Efficiency

  • Active params: ~3B of 27.1B total (25.1B body + 2.0B n-gram memory; 180 experts, 8 per token, 40 layers)
  • Context length: 262,144 max (config); card-tested to 75k; llama-server recommended -c 16384
  • VRAM (fp16 rough): ~54 GB → quant required for real use. Q8_0 ≈ 27 GB; Q5_K_M fits a 16 GB card with -ot "per_layer_token_embd=CPU" (memory ~2.1 GB at Q8 moves to system RAM); routed experts can also go to RAM (4–8 tok/s CPU-expert speed). GGUF ladder Q8_0→Q3_K_M on logic65/Whittle-Next-27B-A3B-GGUF.

What makes it notable

The cheapest local way to run a Qwen4-Next-style (qwen4_exp) hybrid architecture: full attention every 4th layer with linear attention elsewhere, 4 hyper-connection streams, per-layer embeddings, and a 2B-row hashed n-gram memory whose contents were exactly transferred from Qwen3.8-Flash-Next (not re-fit). Unlike most custom-arch models, it serves on stock llama.cpp with no patches (Q8_0→Q3_K_M GGUFs). Reasoning quality tracks its Qwen3.6-35B-A3B parent at a fraction of the active params, and it reproduces Qwen3.8 thinking format (--reasoning-format deepseek compatible). Caveats: maths is at 26B level (GSM8K 86.5% on a 200-question subset), long-context exact-identifier recall degrades past 26k vs the parent, greedy decoding loops (sampling required, thinking budgets ≥4k), and the single-author distillation was “hours, not weeks” — the full distillation from Qwen3.8-27B is unfunded. Nice card hygiene: full training logs, checkpoints, and eval replies published in-repo.

See also