bind1 is the 2026 competition generation of a planned architecture ladder built around
explicit role binding; the accompanying paper describes it as a microkernel loop LM. Its
successor, bind3 — a governed-iteration design whose authority chain learns when to trust
the iterative pathway (whose original backup-pathway motivation did not survive the revised metric — see the honest notes below; the 2027 question is now stated against the leakage-free standard) — is planned as our
BabyLM 2027 entry. Both generations follow the same policy: present the most honest,
most complete account of what the mechanism does and does not do.
A 23.9M-parameter causal language model trained from scratch on the official BabyLM 2026
Strict-Small corpus (~10M words), within the 10-epoch exposure cap (150M tokens ≈ 9.2 epochs).
The architecture is a weight-tied binding loop: an input block (3 layers), a core block
(4 layers) unrolled T=3 times with an explicit role-binding write into a reserved
64-dim slice per iteration, and an output block (3 layers) — effective depth 18.
A learned trust signal (v_gain) couples the model's self-consistency estimate to how much
each iteration's re-binding is trusted during training.
Entry id (internal): bind1_tt3_s0 (physical run name loop2_full), random seed 0
(BABYLM_SEED=0), frozen 2026-07-05 before any replication seeds were trained
(no post-hoc seed selection).
Track: Strict-Small. Backend: causal.
Architecture at a glance
input ─▶ [labeling] bind a soft, revisable logic-role to each term
│ (written into a dedicated 64-dim role slice; re-stamped
│ each iteration, never accumulated; content untouched)
▼
[inference] one weight-tied core pass — no bypass path, by design
▼
[consistency] a per-position verdict v on the result
▼
[volition] next iteration's binding TRUST hears that verdict
│ through a learned gain + per-role experience priors
└──────▶ re-bind … (×T) ─▶ next-token logits
Grammar competence lives partly in the iterations (+3–4.5 BLiMP, 4/4 seeds); the
entity-tracking effect lives in the binding write itself — formed during training
because of the loop, harvestable in a single pass at inference (as measured by the
full-item-set metric; see the metric-revision section below for what the revised
leaderboard standard changes about this reading). Every pathway is
instrumented (see train_loop2_full.json), and the audit script can tell you whether any
exported checkpoint's loop is live or bypassed.
Why this entry might matter beyond its scores
Three things in this work are, we believe, worth scrutiny independent of leaderboard position
(each stated with its honest scope: 24M params, one benchmark family, one architecture):
An inversion of the test-time-compute arrow. In our data, iterating during training
is what makes the binding capability form at all — yet at inference the capability is
harvestable in a single pass (the trained-depth sweep and the from-scratch controls in the
companion papers and the ablations repo carry the full evidence). If this
train-iteratively-deploy-single-pass pattern survives larger scales, it is a
compute-economics counterpoint to scaling inference-time compute: buy the capability once
at training time, serve it cheap. We state it as a falsifiable hypothesis, not a claim.
A guard against self-deception in adaptive-compute evaluation. Best-of-$T$ "oracle
headroom" — the standard ceiling reported for adaptive computation — can be pure re-rolled
noise. Our chance-null protocol (compare conditional recovery against the $1/(k{-}1)$
re-roll baseline) returned both verdicts in this very repo's data: no exploitable signal
in three healthy seeds, genuinely above-chance recovery in the collapsed one. Our own
+8-point "headroom" died by this test before the real signal was found. We think any
test-time-compute result reporting best-of-$N$ ceilings benefits from this control.
The binding write, and exactly what is new about it. Role-filler binding is a classic
problem (TPR; TP-Transformer; SysBinder) and our write primitive is borrowed (NTM/delta-rule)
— all cited. What we found no essential precedent for, after an adversarial prior-art
search, is the wiring: a consistency verdict adjusting next-iteration binding trust
through a learned gain plus per-role experience priors — and the empirical result that the
write itself (not iterative re-binding) carries a 4/4-seed paired entity-tracking gain
(full-item-set metric; see the metric-revision section below),
on an instrumented pathway that lets us audit when it works, when it collapses, and when
it is decorative.
The model is fully self-contained (modeling_babylm.py ships in the repo); forward() runs the
whole loop and returns standard CausalLMOutput(logits, loss). Empty-context, stateless across
examples (competition-compliant: no external memory is used in training or evaluation).
Results (official babylm-eval, zero-shot, final checkpoint)
Task
Score
BLiMP
65.51
BLiMP supplement
58.35
COMPS
51.11
Entity tracking — full item set (public pipeline standard)
39.55
Entity tracking — leaderboard standard (nothing-removed, since 2026-07-07)
19.22
ppl (held-out, internal)
9.4
GLUE fine-tuning (official protocol): BoolQ 67.9 · MNLI 45.1 · MRPC-F1 82.2 · QQP-F1 62.9 ·
RTE 54.7 · MultiRC collapsed to the majority class (F1 0.03 — shared with our size-matched
monolith control; see paper for the tokenizer-separator analysis).
Two entity-tracking numbers: the 2026-07-07 metric revision
On 2026-07-07 the official leaderboard revised its entity-tracking standard (leaderboard
commit a010bbce, "removal of nothing answers"): items whose gold completion contains
"nothing" are excluded from scoring (per-subtask expected counts drop from the 607-series to
the 508-series), and a prediction/gold alignment bug was fixed in the same commit. The public
evaluation pipeline available to participants (babylm-eval commit 02b56cb, 2026-06-28,
with the released BabyLM-2026-Strict-Evals data) scores the full item set — that is the
standard under which this card's 39.55 (and every entity number in the companion paper) was
computed.
Why the removal is sound (our own audit of the released data agrees with it): across all
9,483 entity items, "nothing." never appears as a distractor — whenever it is among the five
options, it is the gold answer, so its presence leaks the answer; the unnormalized
sum-of-log-prob ranking additionally favors it as the shortest option. About 28.5% of items
have a "nothing" gold.
How the 19.22 was produced — no retraining, no new model run. It is a direct
re-scoring of the same frozen checkpoint's already-published per-item predictions: the
gold-contains-"nothing" items are filtered out exactly as the revised leaderboard rule
prescribes, and the resulting macro score matches the public leaderboard display for this
entry exactly. The weights, the predictions, and every other number on this card are
unchanged. All per-item predictions needed to recompute both numbers yourself are in the
companion eval-artifacts dataset.
Leaderboard comparability note. The revision applies to submissions going forward: the
leaderboard reads entity predictions only under the new entity_tracking_filtered key
(leaderboard commit cd1994a, 2026-07-08, explicitly with no fallback to the old key), and
submissions must be re-collated and resubmitted for entity to be scored under the revised
standard. Entries evaluated before the revision may therefore still display full-item-set
entity scores until their authors resubmit — the two standards can coexist on the board for
a while, so entity columns are not always directly comparable across entries. This entry's
displayed 19.22 follows the revised standard.
Honesty note. Under the revised standard, this model and our size-matched monolith
control both land at ≈ the five-way chance level (19–20), in all four seeds (paired
loop-minus-monolith difference: −0.4±0.4 evaluated single-pass, +0.5±0.5 at the entry's
trained depth). The four-seed paired entity-tracking advantage reported on this card and in
the companion paper (+12.7±5.7 at T=1) is carried entirely by the nothing-gold items — it is
a full-item-set-metric result. The ablation structure behind it (the ten-seed necessity test,
the frozen-edge control, the severing test) is unaffected as a description of what the
training mechanism installs; under the revised standard, that effect simply no longer
contributes to the score.
Growth checkpoints (competition requirement)
Branches chck_1M … chck_10M (every ~1M words through the first epoch) and
chck_20M … chck_90M (every ~10M words thereafter; training ends at ≈92M words,
so chck_100M does not exist). Checkpoints were saved on a fixed token cadence
(1.63M tokens ≈ 1M words; 16M tokens ≈ 9.8M words), so nominal branch labels deviate from
exact word counts by ≤1.7% — the mapping table:
branch
tokens
≈words
branch
tokens
≈words
chck_1M
1.6M
1.0M
chck_10M
16.3M
10.0M
chck_2M
3.3M
2.0M
chck_20M
32.3M
19.8M
chck_3M
4.9M
3.0M
chck_30M
48.3M
29.6M
chck_4M
6.5M
4.0M
chck_40M
64.3M
39.4M
chck_5M
8.2M
5.0M
chck_50M
80.3M
49.3M
chck_6M
9.8M
6.0M
chck_60M
96.3M
59.1M
chck_7M
11.4M
7.0M
chck_70M
112.3M
68.9M
chck_8M
13.0M
8.0M
chck_80M
128.3M
78.7M
chck_9M
14.7M
9.0M
chck_90M
144.3M
88.5M
Studying the learning curve (checkpoint branches)
The 18 growth checkpoints double as a learning-dynamics resource — each branch is a fully
loadable model, so questions like "when does entity tracking emerge?" take one line per point:
python
1model = AutoModelForCausalLM.from_pretrained(2"SecludedCorner/bind1-babylm2026-strict-small",3 revision="chck_5M",# any branch from the table above4 trust_remote_code=True)
The first-epoch cadence (every ~1M words, chck_1M…chck_10M) is deliberately dense for
early-emergence studies; later checkpoints follow every ~10M words.
Full evaluation artifacts (companion dataset)
Every number above — and every ablation family behind the honest notes — is downloadable and
recomputable: per-item predictions (with correctness fields), official reports, and the
analysis scripts live in the companion dataset repo
SecludedCorner/bind1-babylm2026-eval-artifacts.
Training telemetry & audit tooling
train_loop2_full.json — the complete training curve (1.8k records): loss/ppl plus the
loop's full mechanism telemetry (verdict-to-trust gain v_gain, trust τ, verdict v,
role entropy, per-iteration binding revision dBind, per-role priors). Every pathway of the
loop is instrumented; this file is the primary evidence that the published mechanism was
live during training (and it is how a silently-bypassed earlier variant was caught).
audit_gate_bypass.py — a standalone audit script: point it at any exported model
directory (python audit_gate_bypass.py <model_dir>) to check whether the loop actually
contributes to the forward pass or has collapsed to a bypass. Reproduces the audit reported
in the accompanying paper; runs on CPU in seconds.
(dim 384, in 3, core 4, out 3, T 3, seq 256, batch 16, 150M tokens, checkpoint every 16M tokens;
first epoch additionally checkpointed every 1.63M tokens.) Tokenizer: 16k BPE trained on the
Strict-Small corpus only. Full reproduction guide accompanies the paper.
Honest notes (the complete picture, including negatives)
The submitted checkpoint is seed 0; the science is four-seed. Competition rules score one
checkpoint — ours was frozen 2026-07-05, before any replication was trained (no post-hoc
seed selection; in hindsight it is also the strongest of the four on entity tracking, but no
claim depends on that). Every headline claim is replicated across four random seeds with
paired statistics: the single-pass ($T{=}1$) binding write beats the same-seed monolith on
entity tracking in 4/4 (paired +12.7±5.7 — full-item-set metric; under the 2026-07-07
revised leaderboard standard this advantage is absent, see the metric-revision section),
BLiMP stays above the GPT-2 baseline in 4/4
(66.1±0.4). Seed variance is large and one seed's write collapsed outright; full tables in
the paper, nothing hidden. The replication checkpoints are in this repo (branches
seed1/seed2/seed3) so the paired claims are verifiable end-to-end.
What inference-time iteration does is two-sided, and we report both sides.
It helps grammar in every seed (BLiMP +3.2 to +4.5 over single-pass, 4/4 — one reason the
entry runs at $T{=}3$). On entity tracking it erodes the healthy write (3/3 seeds,
monotonically), yet in the one seed whose write collapsed it partially rebuilds tracking —
and a per-item chance-null analysis reads that recovery as above the 25% re-roll null
(37–45%) under the pre-revision item set.
The same analysis shows no exploitable per-item headroom in the healthy-write seeds.
Post-revision update (2026-07-09): re-scored under the leaderboard's revised entity-tracking
standard (removal of "nothing"-gold items, commit a010bbce), the collapsed-write seed's recovery
rate falls to 23.4–24.7% ≈ the 25% re-roll null, and the recovered items are 60–70% "nothing"-gold —
the recovery restores the expression of a state-blind completion prior, not tracking. We retire the
backup-pathway reading and keep the chance-null protocol, which is what caught it (in both directions, twice).
The trust edge (v_gain) is causally inert at inference in all four seeds, but
training-relevant: frozen from scratch, the single-pass advantage fails to form in three of
four seeds (and formed anyway in the fourth) — a training scaffold that raises the odds the
write forms, not a strict necessity.
Learning when iteration carries signal at all — now judged against the revised, leakage-free
standard, under which the 2026 recovery signature did not survive — is the core mechanism question
the 2027 generation (bind3) must answer before it earns a governed-iteration design.
Citation
Yulin Yang (ORCID 0009-0007-4827-8449). A Microkernel Language Model: Reasoning as
Mutually-Supporting Aggregates, and Why Its Parts Must Be Judged Together. BabyLM Challenge 2026
(Strict-Small track) submission.