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topic, status, date, deciders, reconstructed, extends
topic status date deciders reconstructed extends
the mesh accepted 2026-09-18 jochen false 0010-delivery.md

83. One push leaves the mesh consistent

Context

A provision is minted while composing the consumer's node; the provider's grant list is a pure read of secrets already issued from it. So assigning a cross-node consumer and pushing its node produced a consumer that retried forever against a provider that had never heard of it, until the provider's node was pushed a second time — an action with no signal to take, documented nowhere, and invisible whenever consumer and provider share a machine (issue 057).

Two remedies were on the table: cascade — a push also delivers to the machines its compose changed — or report — a push says "now push the provider" and leaves the act to the operator.

Decision

A push finishes what it starts: after composing and sending the named node, the controller flushes every other machine that is now behind — whose declaration differs from what it was last sent — by name, in the push's own output, converging over a bounded number of rounds (a flushed send may itself mint).

Behind is measured against what a machine was last sent, not against a before/after snapshot of this push. The mint that makes a provider behind happens when the consumer is assigned or its account issued — before push runs at all — so by push time the provider already differs from what it holds, with no in-command delta to detect. The only durable signal is "what it should be" versus "what it last received", which is the same comparison push --behind already makes.

A machine behind for an unrelated reason is flushed by this too, and that is correct rather than a cost: a named push that knew a machine was behind and left it so would be the very silence this decision removes. The narrower reading — flush only what this push provably changed — was rejected because it cannot see a mint that a prior command performed, which is precisely the 057 case.

Reporting alone was rejected because it converts a derived fact the controller already holds into an operator obligation, and an obligation enforced by nothing is issue 057 restated. The declaration is computed from the whole mesh; delivering a mesh that is knowingly inconsistent and merely saying so would make "push succeeded" mean less than it says.

Consequences

  • One push is sufficient for a cross-node consumer: the provider's grants arrive from the same act that minted the provision. The undocumented rule "push the provider node too" ceases to exist rather than becoming documentation.
  • A named push delivers to every machine that is behind, not only the one named — each named in the output, never silent. push --behind remains the way to reconcile the mesh without naming a node; a named push now carries the same guarantee for the machines its work touched and any others already waiting.
  • How this is checked: the built-store-cross-node bed registers a cross-node consumer, pushes only the consumer's node, and asserts the provider minted its vhost — the workaround push is removed, so a regression fails the bed.