Compatibility

What the runtime works with.

A precise map of the plants, problem structures, and domains TrueLoop Compute drives — separated cleanly into what we have demonstrated in controlled simulation and what we project from those results. No claim here rests on a regime we have not run.

The runtime, in one paragraph

A model-free feedback layer that converges from the first measurement.

TrueLoop Compute is a model-free, retained-state feedback runtime. It sits between your application and a physical or parametric substrate and closes the adaptive loop: each round it reads one measured statistic, compares it to where you want to be, and returns the next configuration — driving on the measured residual itself, not on an estimated gradient or a model of your device. Because the state lives in the configuration, it carries forward across related problems instead of restarting. It discovers each channel’s drive direction from your measurements, so it adapts to the actual sign and shape of your plant rather than assuming one.

That design defines exactly where it wins — and where it does not. The requirement is a locally monotonic, writable loop: a configuration you can set, a measurement you can read, and a response that moves consistently in one direction as you move each control. Below is everything that satisfies that, and the honest boundaries that do not.

How to read the evidence
Validated demonstrated in controlled benchmarks against fairly-tuned baselinesProjected follows from a validated result; awaiting hardware confirmationOut of scope tested and shown not to fit, or structurally excluded
Plant & transfer types

Control-to-observable maps it drives

Each of these was run through the live runtime in regulation mode across multiple seeds. The runtime learns each channel’s sensitivity sign from a short measured probe, so polarity, gain, and mild coupling are handled automatically.

Plant typeStatusNotes
Phase–power (cos²)
p = ½(1 + cos φ)
ValidatedThe canonical interferometric transfer. Converges across the full output range including extreme targets.
Negative-sine
m = −½ sin φ
ValidatedIncludes targets that require crossing φ = 0 into the negative branch. The sign-discovery probe handles this.
Positive-sine
m = +½ sin φ
ValidatedOpposite polarity to the above; learned from measurement, no configuration needed.
Linear, positive gain
m = kφ, k > 0
ValidatedAny positive gain, including small (0.3×) and large (5×).
Linear, negative gain
m = kφ, k < 0
ValidatedNegative gain is driven correctly via the measured sign — a case fixed-direction loops get wrong.
Saturating (tanh)
m = tanh φ
ValidatedSmooth saturating response; converges within the monotonic region.
Coupled / crosstalk
outputs share inputs
ValidatedMild channel coupling (neighbour crosstalk) is absorbed by the per-channel residual drive.
Mixed sign per channel
polarity varies by channel
ValidatedEach channel discovers its own direction independently in the same session.
Drifting / time-varying
target or plant drifts
ValidatedThe core strength: retained momentum tracks a moving target under one read per round.
Fold-back / periodic
many φ → same output
Out of scopeA probe measures a local slope; a globally ambiguous response is genuinely out of envelope and trips the saturation flag.
The unifying requirement is local monotonicity: within the operating range, moving a control moves its observable consistently in one direction. Sign, gain, and shape are learned; only a response that folds back on itself across the range is excluded.
Problem structure

Whether a task fits follows its structure, not its label

The runtime drives objectives that live in the measured marginals. When the value of a problem is carried in those marginals it fits; when it lives in correlations the marginals cannot see, it does not.

DIAGONAL

Diagonal / separable

QUBO, resource allocation, feature selection, threshold setting — cost reads directly from the measured bits.

Strong fit
SPARSE

Sparse / banded

Routing on local graphs, scheduling, MPC plans, beamforming — local structure the marginals resolve.

Strong fit
REGULATION

Regulation / tracking

Calibration, sensor fusion, drift correction, setpoint holding — the most-validated regime.

Strong fit
DENSE

Dense correlation

Attention allocation, clustering, graph partitioning, inference paths — value lives in pairwise structure marginal feedback cannot reach.

Out of scope
VARIATIONAL

Variational energy (VQE / QAOA)

Tested thoroughly; the objective sits in two-qubit correlations the loop cannot observe. We do not sell it here.

Out of scope
LOW-RANK

Low-rank / global

Problems whose optimum depends on a global low-rank structure rather than local readouts.

Out of scope
Domains

Where these shapes show up in practice

DomainStatusWhat the runtime does there
Photonic mesh calibration
MZI phase locks, drift
ValidatedHolds per-tap power at setpoint under thermal drift, one detector pass per round. Self-configuration is mature in the field; our edge is the retained-state tracking.
Drifting sensors / NDT
ultrasonic, GPR, arrays
ValidatedContinuous residual correction holds calibration as the instrument drifts — the measurement-limited regime it is built for.
Variational quantum (calibration)
gate-angle, readout point
ProjectedHolding a single-rotation observable at setpoint under drift. Control, not variational solving.
RF / microwave tuning
phase shifters, match nets
ProjectedLocal, monotonic, writable — fits the envelope; projected from the validated control results.
AI inner-loop decisions
routing, scheduling, MPC
ProjectedThe fast decision layer beneath perception, warm-started across related decisions; projected from the deadline and warm-start results.
Variational energy minimization
VQE / QAOA solving
Out of scopeStructurally excluded — see problem structure above.
What we project, and on what basis

From validated to projected — the honest chain

Two results are demonstrated in benchmarks: the sub-quadratic convergence cost (measured ~n1.3, 95% CI [0.9, 1.5], over n = 12–48) and the deadline crossover, where classical search collapses to near-random while the runtime still returns a usable solution. From these we project — we do not yet claim — that the feasibility advantage extends to larger problems under tight deadlines, within the structural envelope above.

That projection rests on two hypotheses we state openly: that the exponent holds beyond the sizes we can brute-force-verify, and that hardware delivers a favourable optical-to-digital cost ratio. The deadline timing model is the one load-bearing assumption still awaiting on-hardware confirmation; a hardware pilot is the experiment that converts it from projected to demonstrated. We would rather tell you that than overstate it.

Not sure if your loop fits?

Describe it — we will tell you honestly, even when the answer is no.

The fit finder on the homepage classifies your problem in a minute, and the client returns DECLINE when a conventional method already wins. Honesty about the boundary is the product.