jev-qwen: Jev-style typed-decision adapters for Qwen3.5-4B-Base

LoRA adapters from the Small Jev experiments (Patrick Dugan, Red Team Gladiatorics). TypeSafe's Jev is described as a "System One" model: it returns a typed, calibrated decision over a pre-enumerated output space from a single query. These adapters give an open 4B base model a single-pass, option-scored readout of that kind. They are benchmarked against compact looped decoders, TRM skill gates, script/LDT/Control-Harness gates and a 1-bit 8B LLM.

This is not Jev. Jev's weights and architecture are not public; nothing here measures Jev.

• Code, configs, pre-registration, reports: https://github.com/MoralityLabAI/jev-qwen
• Paper draft: paper.pdf in this repo (also paper/ on GitHub)
• Aggregate run records: results/xbench/<suite>/<arm>/record.json. Item-level records are not published, because they contain held-out evaluation items of other projects.

Adapters

All adapters are LoRA r16 / alpha 32 on q/k/v/o, the DeltaNet projections (in_proj_qkv, in_proj_z, out_proj) and the FFN (gate/up/down) of all 32 layers: 30.5M trainable parameters, 0.72% of the model. Each was trained for 300 steps. _s0, _s1, _s2 are training seeds; seed 0 is the pre-registered arm.

Folder	Arm	Training
adapters/v1_lora_s{0,1,2}	J-V1	2,400 synthetic decision questions (8 families, difficulties 1-3) in three formats: option scoring, short answer, one-line reasoning
adapters/v1c_lora_s{0,1,2}	J-V1c	as V1, with a Brier loss on the option distribution
adapters/v1c_lr3_s0	J-V1c-lr3	V1c at 3x the learning rate (a control)
adapters/v2b_lora_s{0,1,2}	J-V2b	as V1, with layers 12-15 run twice in every training forward
adapters/v1_rmp_s{0,1,2}	J-V1-rmp	V1 recipe on 2,400 RMP train-region rows (pointer chasing, gating, reachability, sudoku4)
adapters/v2b_rmp_s{0,1,2}	J-V2b-rmp	V2b recipe on the same RMP rows
adapters/multi_lora_s{0,1,2}	J-multi (SPEC-U1)	V1's recipe on the training splits of the utility suites in their own label spaces: V1's 2,400 decision questions, J-V1-rmp's 2,400 RMP rows, the S2 commit/veto train split (x3), hermes-lite's registered S7 train rows (x4, shuffled shortlists); 714 steps
adapters/multi_loop_s{0,1,2}	J-multi-loop (SPEC-U1)	J-multi with layers 12-15 run twice in training (use the loop at inference)

The V2b adapters expect the loop at inference: layers 12-15 run twice. The repo's external layer-schedule driver does this (src/jevq/looped.py, LoopSpec(12, 16, 2)). With the stock forward they behave like a one-pass exit, which is less accurate.

Loading

from transformers import AutoModelForCausalLM, AutoTokenizer
from peft import PeftModel

base = AutoModelForCausalLM.from_pretrained("Qwen/Qwen3.5-4B-Base", torch_dtype="bfloat16")
tok = AutoTokenizer.from_pretrained("Qwen/Qwen3.5-4B-Base")
model = PeftModel.from_pretrained(base, "AlephFunk/jev-qwen", subfolder="adapters/v1c_lora_s0")

The choice readout renders the options as single-token labels (" A", " B", ...) in a few-shot prompt and takes a softmax over those label logits at the answer position: one forward pass, no emitted tokens. See src/jevq/xbench/jrunner.py.

Headline results (from the paper)

• Single pass vs reasoning. V1 scores 0.880 on the 1,000-item decision suite (base model 0.713). It is within 4.5 points of its own one-line reasoning readout, at 1/21 of the paired latency.
• Calibration. V1c has a lower ECE than V1 in all three seeds (0.035-0.055 vs 0.069-0.078), with no accuracy cost.
• Recurrence. Training with the loop on the mixed suite does not beat V1 (falsified in three seeds). On RMP rows the loop adds hops within the trained depths in every seed. Neither extrapolates past depth 8; only emitted reasoning does.
• Control. Under a scripted evidence-injection ladder, V2b at its trained depth flips 0 of 162 deny decisions over three seeds; V1 flips 14. As monitors on the Control-Harness dev pack, the single-pass arms stop 9 of 10 scripted attacks. All of them miss the duplicate-lineage quorum attack with full confidence.
• Reliability. No Jev-style adapter meets the pre-registered reliability rule on any suite. Where the decision state is typed, scripts and 6k-17k-parameter TRMs are smaller and already reliable.

Follow-up U1: training on the target label spaces (three seeds, pre-registered)

Arm (mean over seeds)	S1 depths 1-8	S2	S4	S7, shuffled
V1	0.351	0.968	0.868	0.870
J-multi	0.632	1.000	0.867	0.880
J-multi-loop, 2 passes	0.691	1.000	0.864	0.898

• Transfer: J-multi removes most of V1's transfer cost on S1 (Holm p = 4e-82) with no loss on S4 (non-inferior).
• Calibration: better than V1 on S4 in every seed.
• Routing: it does not route better on shuffled S7.
• Specialist: it stays about 2 points below the single-task J-V1-rmp on S1.
• Loop: adds S1 accuracy within trained depths (p = 2e-8), unevenly across seeds.
• Reliability: no Jev-style adapter meets the pre-registered rule on any utility suite. See reports/ubench/ on GitHub.

Limitations

• The tasks are synthetic and templated.
• Two control suites are underpowered (18 and 11 cases in the unsafe class).
• The adaptive attacker was too weak to test adaptive pressure.
• Three seeds per arm. Details and every deviation are in notes/xbench-log.md on GitHub.