Field notes
Architecture from inside the control loop.
Market, Routing, Bidding, Execution, Checkpointing: five systems borrowed from places that already solved them hard, joined so a workload can finish. One note per phase, each marking where the shipping code is narrower than the contract it implements. For the research rather than the architecture, see Labs.
Published
006-
Five systems, one control loop.
Nodus is not five products bolted together. It is a capacity book, a pure router, a reservation ledger, a generation reconciler, and portable progress, wired so reclaim re-enters the same path.
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The capacity book is not a catalog.
How we normalize supplier inventory into TTL’d offer snapshots, score health independently of price, and keep the router off every provider critical path.
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The router is pure on purpose.
Execution envelopes, cost-to-completion scoring, fallback graphs, and why a B200 the work does not need is a routing failure even when it is available.
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A bid ceiling is a completion budget.
Quote → bid → lease as financial truth. Recovery reserve, idempotent reservation attempts, and why we refuse to treat bidding as a speculative trading product.
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Launch is a midpoint.
Desired vs observed generations, runner identity before
running, and the reconciler that makes controller restarts and duplicate messages safe. -
Local disk is not progress.
PrepareCheckpoint, SHA-256 verified commits, immutable manifests, and Postgres compare-and-set for the latest pointer, so reclaim cannot erase the run.
Written but not scheduled
02-
Unscheduled
Fencing and the reclaim saga.
Signed reclaim → fence gen N → restore from latest manifest → re-route → reserve → gen N+1. Compensating actions at every step, and what the postmortem record must contain.
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Unscheduled
Multi-stage DAGs without shared process state.
Manifest-only handoffs, per-stage continuity modes, and why a completed upstream stage never re-runs after a downstream reclaim.
Both are drafted. Neither ships until reclaim runs against live wholesale capacity, because we would rather leave them dated than write up a path we have only exercised in a drill. Argue with a design choice.