POISE
Loading verification record

01 The control loop

Load balancing,
made observable.

Composable Rust primitives for selection, affinity, health, discovery, and dispatch. Six ownership boundaries, drawn once, so the whole request path is legible before you write a line against it.

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Isometric map of the Poise control loop. Discovery publishes an immutable snapshot; health and load signals narrow it to an eligible candidate slice; a policy returns an index; Tower dispatches using a readiness permit it already held; and the classified outcome returns along a feedback lane into load trackers, the outcome window, health circuits, and metrics.
Shape says what a thing is. Drums hold mutable state you write to, the stack is one immutable revision over older ones, plates carry borrowed candidates, the hexagonal prism is the only solid that turns a slice into an index, instruments measure, and dashed silhouettes are optional or outside the library. Color says who owns it. No single crate owns very much, which is the point of the split.

02 The invariant orrery

Every force,
held in relation.

The same primitives as a live field: each capability in orbit, replayed against the verification layer that currently holds it.

01 / 05 Property laws 3,584 generated cases

← → step · space pause · 1–7 focus

Bounded renderer 0 particles · 1.5× DPR max

03 / The premise

Selection is only the visible moment. Poise makes every force around it explicit.

Membership. Eligibility. Choice. Dispatch. Feedback. Each concern has a boundary you can inspect, compose, and replace.

04 / Capability atlas

A policy system,
not a single algorithm.

Select a family to reorganize the orrery. The same symbolic language describes the primitive, its state, and the proof currently exercising it.

05 / Verification ledger

Proof is part
of the interface.

Recorded local baseline
Awaiting verification data

P / 01 passed

Ordinary tests

Examples, edge cases, distributions, cancellation, and transactional failure behavior across the workspace.

240 authored test entry points

P / 02 passed

Property laws

Generated inputs test selection safety, minimal disruption, exact replay, conservation, and topology metadata.

3,584 generated cases per run

P / 03 passed

Mutation gate

The suite must reject every terminating, viable behavioral mutation. Equivalent rewrites are reviewed, never hidden.

0 viable survivors / 642 sites

P / 04 passed

Loom models

Exhaustive scheduler exploration checks in-flight accounting and health-state transitions under hostile interleavings.

6 scheduler models

P / 05 passed

Compiler floor

The dependency graph and public surface are held to the declared Rust 1.85 minimum supported version.

1.85 declared Rust MSRV

06 / Composition path

The hot path stays small.

  1. 01Membershipversioned snapshots
  2. 02Eligibilityhealth + topology
  3. 03Selectionpure policy decision
  4. 04Dispatchreadiness retained
  5. 05Feedbackbounded signals
use poise_core::{Backend, Policy, policy::RoundRobin};

let backends = [Backend::new("a"), Backend::new("b")];
let mut policy = RoundRobin::new();

let selected = policy.pick(&backends, &())?;

07 / Begin with the contracts

Make the easy policies easy.
Keep the hard ones possible.

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