NewPublic SAE feature database is live.

Aquin is the research company reverse engineering intelligence with interpretability.

We build the tooling to debug and improve ML models by pin-pointing issues and simulating fixes, from reducing hallucinations to ensuring safety, based on mechanistic interpretability.

Backed by

Emergent Ventures
Emergent Ventures
Founders Inc
Founders Inc
The Residency
The Residency
NVIDIA Inception
NVIDIA Inception

build models with same precision as writing code.

Observe features and layers. Simulate training runs and catch failures. Diff base vs fine-tuned to see exactly what changed and why. Trace any output token back to the exact prompt span and layer where the answer formed.

Observe & Find
prompt
What
is
the
capital
of
France
?
response · inherited signal
The
capital
of
France
is
Paris
.
Simulate & Fix
s0s25s50s75s100lossgrad norm
click a checkpoint ● to compare outputs
Debug & Improve
Prompt injection
71%
Role confusion
58%
Suppression
44%
Boundary bypass
33%
Context bleed
29%
Multi-turn drift
18%
trojan layer scan
layers.8.mlp.down_proj0%
layers.4.mlp.gate_proj0%
layers.12.self_attn.v0%

Simulate, debug and improve ML models.

Inspect dense LLMs, MoE, vision, and embedding models. Trace any output token back to the exact prompt span and layer where the answer formed. Simulate LoRA, QLoRA, DPO, and distillation runs, catch failure modes before they compound, and diff base vs fine-tuned to see exactly what changed and why.

input tokensmulti-head attentionfeed-forwardoutput

build transformers & llms

layered attention

W frozenA rank-rB rank-r

simulate lora

low-rank weight adaptation

Interpret your existing infrastructure and pipelines.

Use the aquin watch CLI to observe external training runs. Run aquin watch init, ingest metrics JSONL with aquin watch ingest, and store runs locally under ~/.aquin/watch/. After aquin connect --name, loss, learning rate, and grad norm charts mirror to the web panel. Tail live with ingest --follow or replay with aquin watch on a run id.

$pip install aquin
Read Docs
aquin cli
aquin login
/docs/agent · cli/aquin

The science: Mechanistic interpretability

Mechanistic interpretability reverse-engineers how neural networks compute, not just what they output. Aquin applies sparse autoencoders, logit lens, activation patching, and causal tracing to expose which features fire, which layers encode a concept, and which circuits produce each token. Stop guessing why a model hallucinated, drifted, or refused, trace the answer back to the exact prompt span that caused it and patch at the source.

causal trace
TOKENSEMBEDATTENTIONSAEOUTPUTWhatiscapitalFranceh1h2h3h4f1f2f3f4Paristop-1
active row
firing feature
inactive
feature space

Work with us

Interpretability tooling, custom SAE databases, mechanistic audits, circuit reports, and hands-on research, experiments, and studies for teams of all sizes. Reach us at aquin@aquin.app

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