A gate judges its own send and the build it sent, and never puts the controller back behind its store (hq issue 352)

On 2026-10-09 a release's gate on the control node read the machine's
report against a newer send another plan had just made there, failed
three builds the machine had reported healthy, and put them back on
every machine to a controller older than the store's schema; that
controller then passed the newer plan's gate from its own health.

- A gate keeps what its send carried (digest, sequence) and reads the
  report against it; a report on the last send is on it too.
- A gate judges only the build the machine was last sent: another build
  there supersedes the judging — no verdict, nothing put back.
- A controller is told its build (MESH_CONTROLLER_VERSION, ${version}
  in a process's env) and records how far it reads the store's schema;
  a put-back to a build that reaches less, or never said, is refused
  and the current build kept, said as urgent.
- A release's open gate holds other sends of its modules there, and a
  plan's own first send waits on it.

cmd/mesh-controller/acting.go

@@ -5,6 +5,7 @@ import (
 	"errors"
 	"fmt"
 	"os"
+	"strings"
 	"sync"
 	"time"
 
@@ -179,7 +180,21 @@ func (a *actor) release() {
 // holderOf is this process as the lease's holder.
 func holderOf(instance string) lease.Holder {
 	host, _ := os.Hostname()
-	return lease.Holder{Instance: instance, Host: host, Build: version}
+	build := runningBuild()
+	if build == "" {
+		build = version
+	}
+	return lease.Holder{Instance: instance, Host: host, Build: build}
+}
+
+// RunningBuildVar is where the declaration tells this process which build it is (module.json, the
+// controller process's env): the version its bundle is delivered as, `${version}` composed by the
+// catalogue from the bundle's digest. Empty for a process placed by hand.
+const RunningBuildVar = "MESH_CONTROLLER_VERSION"
+
+// runningBuild is the version of the build this process is, or empty when the declaration did not say.
+func runningBuild() string {
+	return strings.TrimSpace(os.Getenv(RunningBuildVar))
 }
 
 // serveUnderTheLease takes the lease for the serving controller, waiting while another holds it, and

cmd/mesh-controller/gate.go

@@ -87,6 +87,9 @@ const (
 	healthWaiting
 	healthNotYet
 	healthBroken
+	// healthSuperseded is a judging that cannot go on: the machine was sent another build of the module
+	// after the gate's send (novox/hq issue 352). No verdict on the build judged, and nothing put back.
+	healthSuperseded
 )
 
 // served is what one machine's node tools answered the bus's discovery with.
@@ -122,6 +125,39 @@ type gateFacts struct {
 	// groupsAdded is, per module, whether the move judged puts an account in a group its previous build did
 	// not (issue 318 review): the only move whose wait for a new login is excused.
 	groupsAdded map[string]bool
+	// sent is, per machine, the declaration the gate's own send carried there (novox/hq issue 352): a
+	// report is held against it, never against the send made last. sentBuilds is what each machine was
+	// last sent of every module, and judged the commit of each module this gate judges: a machine last
+	// sent another build of the module is not running the build judged.
+	sent       map[string]inventory.SentDeclaration
+	sentBuilds map[string]map[string]string
+	commits    map[string]string
+}
+
+// reportedOn says a machine's last report is on what the gate sent it (novox/hq issue 352): on that
+// declaration, or one it was sent after it — or, for a gate kept before sends were kept on it, on the
+// declaration last sent. On 2026-10-09 a release's gate read the control node's report against a newer
+// send another plan had just made there, and failed three builds the machine had reported healthy as
+// "has not reported on what it was sent".
+func (f gateFacts) reportedOn(machine string, r inventory.Reported) bool {
+	if sent, kept := f.sent[machine]; kept {
+		return sent.ReportsOn(r)
+	}
+	return r.Current
+}
+
+// supersededOn says the machine was last sent another build of the module than the one this gate judges
+// (novox/hq issue 352): the judging cannot go on, whatever the machine reports. On 2026-10-09 a controller
+// put back by one gate judged another gate's newer controller build passed on the same machine, reading
+// the put-back build's health as the newer one's.
+func (f gateFacts) supersededOn(module, machine string) (string, bool) {
+	judged, known := f.commits[module]
+	sent, has := f.sentBuilds[machine][module]
+	if !known || !has || judged == "" || sent == "" || sameCommit(sent, judged) {
+		return "", false
+	}
+	return fmt.Sprintf("%s was sent %s %s after this gate's %s: the build judged no longer runs there, and "+
+		"this judging is superseded by that send's", machine, module, short(sent), short(judged)), true
 }
 
 // gatherGateFacts reads what a judging needs, from the store, the bus and this controller's memory. A
@@ -199,9 +235,12 @@ func judgeHealth(module, component string, m catalogue.Manifest, machine string,
 		return healthBroken, fmt.Sprintf("the witness on %s judged the %s %s and %s: %s", machine, r.Component,
 			short(r.From), r.Outcome, r.Why)
 	}
+	if why, superseded := f.supersededOn(module, machine); superseded {
+		return healthSuperseded, why
+	}
 	r, said := f.reports[machine]
 	switch {
-	case !said || r.At == nil || !r.Current:
+	case !said || r.At == nil || !f.reportedOn(machine, r):
 		return healthNotYet, fmt.Sprintf("%s has not reported on what it was sent", machine)
 	case r.Outcome == inventory.OutcomeFailed || r.Outcome == inventory.OutcomeRefused:
 		return healthBroken, fmt.Sprintf("%s %s what it was sent", machine, r.Outcome)
@@ -438,6 +477,21 @@ func judgeMoves(ctx context.Context, open *stores, g *inventory.PlanGate, pairs
 		return "", err
 	}
 	facts.groupsAdded = movesAddingGroups(ctx, open.inventory, g, pairs, shelf)
+	facts.sent = g.Sent
+	facts.commits, facts.sentBuilds = judgedCommits(g, pairs), map[string]map[string]string{}
+	// A module this gate put back at once (putBackBroken) was sent its earlier build by the gate itself:
+	// not another send, and not a judging superseded.
+	for _, m := range g.Returned {
+		delete(facts.commits, m)
+	}
+	for _, j := range pairs {
+		if _, read := facts.sentBuilds[j.node]; read {
+			continue
+		}
+		if builds, known, err := open.inventory.SentBuilds(ctx, j.node); err == nil && known {
+			facts.sentBuilds[j.node] = builds
+		}
+	}
 	// **What is wrong with a machine itself is the machine's** (novox/hq issue 281): read once for each
 	// machine judged, apart from what is wrong with a module there, and never pinned on the module the
 	// gate happens to be kept on.
@@ -474,6 +528,13 @@ func judgeMoves(ctx context.Context, open *stores, g *inventory.PlanGate, pairs
 		if _, seen := reading[j.module]; !seen {
 			modules = append(modules, j.module)
 		}
+		if h == healthSuperseded {
+			// Decided at once (novox/hq issue 352): nothing of this gate's can be judged on a machine that
+			// was sent another build of it, and nothing is put back — the later send is what runs there.
+			g.Failing, g.Last = nil, ""
+			decide(g, inventory.GateSuperseded, said, now)
+			return g.Verdict, nil
+		}
 		if h == healthBroken && !slices.Contains(g.Broken, j.module) {
 			g.Broken = append(g.Broken, j.module)
 			if g.BrokenWhy == "" {
@@ -577,6 +638,40 @@ func judgeMoves(ctx context.Context, open *stores, g *inventory.PlanGate, pairs
 	return g.Verdict, nil
 }
 
+// judgedCommits is the commit of each module a gate judges: the gate's own To for its module, and each
+// carried move's. Pure.
+func judgedCommits(g *inventory.PlanGate, pairs []judged) map[string]string {
+	out := map[string]string{}
+	for _, c := range g.Carried {
+		if c.To != "" {
+			out[c.Module] = c.To
+		}
+	}
+	if g.To != "" {
+		for _, j := range pairs {
+			if _, has := out[j.module]; !has && !slices.ContainsFunc(g.Carried, func(c inventory.CarriedMove) bool { return c.Module == j.module }) {
+				out[j.module] = g.To
+			}
+		}
+	}
+	return out
+}
+
+// sentNow is what each machine was just sent, read after a send for the gate to keep (novox/hq issue
+// 352): a machine whose send is not on record is left out, and its report is read as before.
+func sentNow(ctx context.Context, inv *inventory.Inventory, machines []string) map[string]inventory.SentDeclaration {
+	out := map[string]inventory.SentDeclaration{}
+	for _, n := range machines {
+		if s, found, err := inv.SentTo(ctx, n); err == nil && found {
+			out[n] = s
+		}
+	}
+	if len(out) == 0 {
+		return nil
+	}
+	return out
+}
+
 // whyFor is a passing gate's why as one module's verdict says it: the send's, and that module's own wait
 // for a person, never another's (issue 318 review).
 func whyFor(g *inventory.PlanGate, module string) string {
@@ -802,6 +897,16 @@ func gateFailed(ctx context.Context, open *stores, p *inventory.Plan, module str
 			"back", module, short(state.Previous), inventory.KeptBuilds))
 		return
 	}
+	if g.Component == lease.ComponentController {
+		// **The controller is never put back to a build older than the store's schema** (novox/hq issue
+		// 352): the build before it carries fewer migrations than the failed one applied, starts behind
+		// its own records, and judges the next gate with what it can read. The current build is kept and
+		// the condition says so; a person decides.
+		if why, ok := controllerSchemaAllows(ctx, inv, previous); !ok {
+			notBack(why)
+			return
+		}
+	}
 	if err := inv.RestoreModule(ctx, previous); err != nil {
 		notBack(err.Error())
 		return
@@ -835,6 +940,53 @@ func gateFailed(ctx context.Context, open *stores, p *inventory.Plan, module str
 	sayRollback(ctx, open, module, g, "")
 }
 
+// controllerSchemaAllows says the store's schema lets this build of the controller be put back: the
+// build recorded, when it served, a reach at or past the highest migration the store has applied. One
+// that never recorded a reach is not proved safe, and is refused as such (novox/hq issue 352). Why
+// says what is kept and why when it is not.
+func controllerSchemaAllows(ctx context.Context, inv *inventory.Inventory, previous inventory.Build) (string, bool) {
+	applied, err := inv.SchemaApplied(ctx)
+	if err != nil {
+		return "what the store's schema reaches cannot be read, so whether the build before it can read it is not " +
+			"known; the current build is kept: " + err.Error(), false
+	}
+	build := versionOfBuild(previous)
+	if build == "" {
+		return fmt.Sprintf("the build before it (%s) names no bundle to know it by, so whether it can read the store's "+
+			"schema (migration %04d) is not known; the current build is kept, and a person decides", short(previous.Commit), applied), false
+	}
+	reach, known, err := inv.SchemaReachOf(ctx, build)
+	if err != nil {
+		return "what the build before it knows of the store's schema cannot be read; the current build is kept: " + err.Error(), false
+	}
+	if !known {
+		return fmt.Sprintf("the build before it (%s, %s) never recorded how far it reads the store's schema — a "+
+			"controller records that when it serves — so it is not proved to read migration %04d, which the store "+
+			"has applied; a controller older than its store starts behind its own records and judges with what it "+
+			"can read, so the current build is kept, and a person decides", short(previous.Commit), build, applied), false
+	}
+	if reach < applied {
+		return fmt.Sprintf("the build before it (%s, %s) reads the store's schema up to migration %04d, and the store "+
+			"is at %04d: a controller older than its store starts behind its own records and judges with what it "+
+			"can read, so the current build is kept, and a person decides", short(previous.Commit), build, reach, applied), false
+	}
+	return "", true
+}
+
+// versionOfBuild is the version a build's bundle is delivered as — its archive's digest, short, as the
+// catalogue names it (`${version}`) — read from the build's artifacts; empty when none is a bundle.
+func versionOfBuild(b inventory.Build) string {
+	for _, a := range b.Made {
+		if a.Kind != catalogue.ArtifactBundle && a.Kind != catalogue.ArtifactArchive {
+			continue
+		}
+		if _, hex, found := strings.Cut(a.Reference, "sha256:"); found && len(hex) >= 12 {
+			return hex[:12]
+		}
+	}
+	return ""
+}
+
 // rollbacks is what a failed send puts back, sent together (novox/hq issue 281): a gate that judged one
 // send judges what it moved as one, and what it found wanting goes back in one send per machine — not
 // in a send for each module, which is the churn that failed the gate in the first place.

cmd/mesh-controller/gate_test.go

@@ -113,9 +113,10 @@ func aGateMesh(t *testing.T) *gateMesh {
 		}
 		for node, h := range g.health {
 			if h == healthNotYet {
+				// Not reported on the send: neither the send made last, nor the gate's own (issue 352).
 				f.rolledBack[node] = nil
 				r := f.reports[node]
-				r.Current = false
+				r.Current, r.Declared, r.ReportedSequence = false, "", 0
 				f.reports[node] = r
 			}
 		}

cmd/mesh-controller/issue352_test.go

@@ -0,0 +1,356 @@
+package main
+
+import (
+	"context"
+	"encoding/json"
+	"errors"
+	"reflect"
+	"strings"
+	"testing"
+	"time"
+
+	"github.com/novox/mesh-controller/internal/catalogue"
+	"github.com/novox/mesh-controller/internal/conditions"
+	"github.com/novox/mesh-controller/internal/inventory"
+	"github.com/novox/mesh-controller/internal/lease"
+)
+
+// novox/hq issue 352: on 2026-10-09 a release's gate on the control node read the machine's report against a
+// newer send another plan had just made there — not against its own send — and failed three builds the
+// machine had reported healthy ("has not reported on what it was sent"), put them back on every machine,
+// to a controller older than the store's schema, and that controller then judged the newer plan's
+// controller passed from the put-back build's health.
+
+// TestReplay352 replays the walk on the backlog fixture: the release sends anchor and anchor reports;
+// another send reaches anchor, unreported; the gate still passes. And a send that moves a judged module
+// to another build supersedes the judging: no verdict, nothing put back.
+func TestReplay352(t *testing.T) {
+	t.Run("a newer send to the judged machine does not unreport the gate's", testANewerSendDoesNotUnreportTheGatesOwn)
+	t.Run("a send that moves the module supersedes the judging", testASendThatMovesTheModuleSupersedesTheJudging)
+}
+
+func testANewerSendDoesNotUnreportTheGatesOwn(t *testing.T) {
+	b := aBacklog(t)
+	ctx := t.Context()
+	inv := b.open.inventory
+	advancePlans(ctx, b.open) // anchor is sent, and the fixture reports it applied
+	// 16:31:37 — another plan sends anchor a newer declaration, which it has not reported on.
+	carried, _, _ := inv.SentBuilds(ctx, "anchor")
+	if err := inv.RecordSent(ctx, nodeID(t, b.open, "anchor"), "d-anchor-newer", carried); err != nil {
+		t.Fatal(err)
+	}
+	reports, _ := inv.LastReports(ctx)
+	for _, r := range reports {
+		if r.Node == "anchor" && r.Current {
+			t.Fatal("the fixture's newer send reads as reported")
+		}
+	}
+	gateEvery, gateBound = 0, 0 // past the bound at once: before the fix, "has not reported" fails it here
+	for i := 0; i < 4; i++ {
+		advancePlans(ctx, b.open)
+	}
+	p := b.release(t)
+	if p.State == inventory.PlanFailed || strings.Contains(p.Note, "has not reported") {
+		t.Fatalf("the release failed on the newer send: %s %s", p.State, p.Note)
+	}
+	if g := p.Release.Gate; g != nil && (g.Sent == nil || g.Sent["anchor"].Digest == "") {
+		t.Fatalf("the gate does not keep what it sent: %+v", g)
+	}
+	if v, found, err := inv.GateOf(ctx, "build-app-c2"); err != nil || !found || v.Verdict != inventory.GatePassed {
+		t.Fatalf("app's pass on anchor was not kept: %+v %v %v", v, found, err)
+	}
+	if current, _ := inv.CurrentBuilds(ctx); current["app"].Commit != "c2" {
+		t.Fatalf("app was put back to %s", current["app"].Commit)
+	}
+}
+
+// A plan's own first send waits while a release judges the same module on that machine with another build.
+func TestAPlansFirstSendWaitsForAReleaseJudgingTheModuleThere(t *testing.T) {
+	b := aBacklog(t)
+	ctx := t.Context()
+	advancePlans(ctx, b.open) // the release judges app c2 on anchor
+	_, _, err := gatedSend(ctx, b.open, "anchor", []inventory.CarriedMove{{Module: "app", Node: "anchor", From: "c2", To: "c3", Build: "build-app-c3"}})
+	if !errors.Is(err, errWalkedElsewhere) || !strings.Contains(err.Error(), "release-") {
+		t.Fatalf("a newer build of a judged module was sent under the release's gate: %v", err)
+	}
+	if len(b.sent) != 1 {
+		t.Fatalf("sent %v", b.sent)
+	}
+}
+
+// A merge plan's judging is superseded the same way: another send moved its module on the first machine.
+func TestAPlansJudgingIsSupersededByASendThatMovesItsModule(t *testing.T) {
+	g := aGateMesh(t)
+	ctx := t.Context()
+	inv := g.open.inventory
+	advancePlans(ctx, g.open) // anchor is sent app c2 first
+	if err := inv.RecordSent(ctx, nodeID(t, g.open, "anchor"), "d-anchor-c3", map[string]string{"app": "c3"}); err != nil {
+		t.Fatal(err)
+	}
+	gateEvery = 0
+	advancePlans(ctx, g.open)
+	p := g.plan(t)
+	if p.State != inventory.PlanSuperseded || !strings.Contains(p.Note, "superseded") || !strings.Contains(p.Note, "c3") {
+		t.Fatalf("the plan is %s: %s", p.State, p.Note)
+	}
+	// Nothing put back: the registered build stands, the build is not marked, and the plan's gate made no
+	// rollback (a release may walk what the other send left waiting on anchor; that is not a put-back).
+	if r := p.Modules["app"].Gate.Rollback; r != "" {
+		t.Fatalf("a superseded judging made a rollback: %q", r)
+	}
+	if current, _ := inv.CurrentBuilds(ctx); current["app"].Commit != "c2" {
+		t.Fatalf("app was put back to %s", current["app"].Commit)
+	}
+	if failed, _ := inv.GateFailed(ctx, "build-2"); failed {
+		t.Fatal("a superseded build was marked failed")
+	}
+}
+
+func testASendThatMovesTheModuleSupersedesTheJudging(t *testing.T) {
+	b := aBacklog(t)
+	ctx := t.Context()
+	inv := b.open.inventory
+	advancePlans(ctx, b.open)
+	// Another send moves app on anchor to a build this gate does not judge.
+	carried, _, _ := inv.SentBuilds(ctx, "anchor")
+	carried["app"] = "c3"
+	if err := inv.RecordSent(ctx, nodeID(t, b.open, "anchor"), "d-anchor-c3", carried); err != nil {
+		t.Fatal(err)
+	}
+	gateEvery = 0
+	advancePlans(ctx, b.open)
+	p := b.release(t)
+	if p.State != inventory.PlanSuperseded || !strings.Contains(p.Note, "superseded") || !strings.Contains(p.Note, "c3") {
+		t.Fatalf("the release is %s: %s", p.State, p.Note)
+	}
+	if !reflect.DeepEqual(b.sent, [][]string{{"anchor"}}) {
+		t.Fatalf("sent %v: a superseded judging puts nothing back", b.sent)
+	}
+	if _, found, _ := inv.GateOf(ctx, "build-app-c2"); found {
+		t.Fatal("a superseded judging kept a verdict")
+	}
+	if current, _ := inv.CurrentBuilds(ctx); current["app"].Commit != "c2" {
+		t.Fatalf("app was put back to %s", current["app"].Commit)
+	}
+}
+
+// A report is on the gate's own send: the declaration itself, or one sequenced after it; a gate kept
+// without its send reads the report against the send made last, as before. Pure.
+func TestAReportIsHeldAgainstTheGatesOwnSend(t *testing.T) {
+	sent := inventory.SentDeclaration{Digest: "d-490", Sequence: 490}
+	for _, c := range []struct {
+		r    inventory.Reported
+		want bool
+	}{
+		{inventory.Reported{Declared: "d-490", Current: false}, true},
+		{inventory.Reported{Declared: "d-491", ReportedSequence: 491, Current: true}, true},
+		{inventory.Reported{Declared: "d-489", ReportedSequence: 489, Current: false}, false},
+		{inventory.Reported{Declared: "other", ReportedSequence: 490}, true},                // the same sequence, said by another digest
+		{inventory.Reported{Declared: "d-495", ReportedSequence: 495, Current: true}, true}, // the last send: this one or a later one
+		{inventory.Reported{Declared: "", Current: false}, false},
+	} {
+		if got := sent.ReportsOn(c.r); got != c.want {
+			t.Errorf("%+v on %+v: %v", c.r, sent, got)
+		}
+	}
+	byDigest := inventory.SentDeclaration{Digest: "d-1"}
+	if !byDigest.ReportsOn(inventory.Reported{Declared: "d-1"}) || byDigest.ReportsOn(inventory.Reported{ReportedSequence: 5}) ||
+		!byDigest.ReportsOn(inventory.Reported{Current: true}) {
+		t.Fatal("a send kept without a sequence is matched by its digest and by the last send alone")
+	}
+	f := gateFacts{sent: map[string]inventory.SentDeclaration{"anchor": sent}}
+	if !f.reportedOn("anchor", inventory.Reported{Declared: "d-490"}) || f.reportedOn("anchor", inventory.Reported{Declared: "d-1"}) {
+		t.Fatal("a gate that kept its send read the report against something other than it")
+	}
+	if !f.reportedOn("laptop", inventory.Reported{Current: true}) || f.reportedOn("laptop", inventory.Reported{Current: false}) {
+		t.Fatal("a gate that did not keep its send does not read the report against the send made last")
+	}
+	// Through the merge plan's first-machine wait too.
+	at := time.Now()
+	state := inventory.PlanModule{First: []string{"anchor"}, FirstAt: &at,
+		Gate: &inventory.PlanGate{Machines: []string{"anchor"}, Sent: map[string]inventory.SentDeclaration{"anchor": sent}}}
+	reports := []inventory.Reported{{Node: "anchor", At: &at, Outcome: inventory.OutcomeApplied, Current: false, Declared: "d-490"}}
+	if step := nextRollout(state, []string{"anchor", "laptop"}, false, reports, at.Add(time.Minute), time.Hour); step.waiting != "" || step.failed != "" {
+		t.Fatalf("the first machine's report on the plan's own send read as none: %+v", step)
+	}
+	reports[0].Declared = "d-480"
+	if step := nextRollout(state, []string{"anchor", "laptop"}, false, reports, at.Add(time.Minute), time.Hour); step.waiting == "" {
+		t.Fatalf("a report on an older send read as the plan's: %+v", step)
+	}
+}
+
+// A gate judges only the build the machine was last sent: last sent another build of the module, the
+// judging is superseded, whatever the machine reports. Pure.
+func TestAGateJudgesOnlyTheBuildTheMachineWasLastSent(t *testing.T) {
+	at := time.Now()
+	f := gateFacts{now: at, reports: map[string]inventory.Reported{"anchor": {Node: "anchor", Outcome: inventory.OutcomeApplied,
+		At: &at, Current: true}}, engines: map[string]string{}, served: map[string]served{}, rolledBack: map[string][]lease.Rollback{},
+		commits: map[string]string{"mesh-controller": "e6b00e2e"}, sentBuilds: map[string]map[string]string{"anchor": {"mesh-controller": "ef26d4cb"}}}
+	taken := at.Add(-30 * time.Second)
+	f.holder = &lease.Holder{Taken: taken, Health: &lease.Health{Ready: true}}
+	h, why := judgeHealth("mesh-controller", lease.ComponentController, catalogue.Manifest{}, "anchor", at.Add(-time.Minute), f)
+	if h != healthSuperseded || !strings.Contains(why, "ef26d4cb") || !strings.Contains(why, "e6b00e2e") {
+		t.Fatalf("a controller build the machine no longer runs: %v %q", h, why)
+	}
+	f.sentBuilds["anchor"]["mesh-controller"] = "e6b00e2e"
+	if h, why := judgeHealth("mesh-controller", lease.ComponentController, catalogue.Manifest{}, "anchor", at.Add(-time.Minute), f); h == healthSuperseded {
+		t.Fatalf("the build sent read as another: %q", why)
+	}
+	delete(f.sentBuilds, "anchor")
+	if h, why := judgeHealth("mesh-controller", lease.ComponentController, catalogue.Manifest{}, "anchor", at.Add(-time.Minute), f); h == healthSuperseded {
+		t.Fatalf("a machine whose send is not known read as superseded: %q", why)
+	}
+	g := &inventory.PlanGate{To: "c2", Carried: []inventory.CarriedMove{{Module: "late", Node: "anchor", To: "c5"}}}
+	if got := judgedCommits(g, []judged{{"app", "anchor"}, {"late", "anchor"}}); got["app"] != "c2" || got["late"] != "c5" {
+		t.Fatalf("judged commits %v", got)
+	}
+}
+
+// A move of another build of a module to a machine where a release or a plan is judging that module
+// waits for that judging; the same build to that machine is already there. Pure.
+func TestAWalkWaitsForAJudgingOfTheSameModuleOnThatMachine(t *testing.T) {
+	at := time.Now()
+	release := inventory.Plan{ID: "release-1", State: inventory.PlanRolling, Release: &inventory.PlanRelease{
+		Gate: &inventory.PlanGate{Machines: []string{"novox"}, Carried: []inventory.CarriedMove{
+			{Module: "mesh-controller", Node: "novox", From: "ef26d4cb", To: "2913c54c"}}}}}
+	merge := inventory.Plan{ID: "plan-1", State: inventory.PlanRolling, Modules: map[string]*inventory.PlanModule{
+		"app": {First: []string{"anchor"}, FirstAt: &at, Commit: "c2", Gate: &inventory.PlanGate{Machines: []string{"anchor"}}}}}
+	f := moveFacts{plans: []inventory.Plan{release, merge}}
+	for _, c := range []struct {
+		module, node, to, want string
+	}{
+		{"mesh-controller", "novox", "e6b00e2e", "release-1"}, // the day's case: a newer controller to the judged machine
+		{"mesh-controller", "novox", "2913c54c", ""},          // the same build: already there
+		{"mesh-controller", "ace", "2913c54c", "release-1"},   // another machine while the first is judged
+		{"mesh-host", "novox", "x", ""},                       // a module the release does not carry
+		{"app", "anchor", "c2", ""},
+		{"app", "anchor", "c3", "plan-1"},
+		{"app", "laptop", "c2", "plan-1"},
+	} {
+		if got := f.walkedBy(c.module, c.node, c.to); got != c.want {
+			t.Errorf("%s %s to %s: walked by %q, want %q", c.module, c.to, c.node, got, c.want)
+		}
+	}
+	release.Release.Gate.Verdict = inventory.GatePassed
+	merge.Modules["app"].Gate.Verdict = inventory.GatePassed
+	if f.walkedBy("mesh-controller", "novox", "e6b00e2e") != "" || f.walkedBy("app", "laptop", "c3") != "" {
+		t.Fatal("a passed judging still holds a move")
+	}
+	release.Release.Gate.Verdict = ""
+	f.plans[0].State = inventory.PlanSuperseded
+	if f.walkedBy("mesh-controller", "novox", "e6b00e2e") != "" {
+		t.Fatal("a closed release still holds a move")
+	}
+}
+
+// The controller is never put back to a build that reaches less of the store's schema than the store
+// has, or to one that never said what it reaches: the current build is kept, and the condition says so.
+func TestTheControllerIsNotPutBackToABuildOlderThanTheStoresSchema(t *testing.T) {
+	open := aMesh(t)
+	ctx := t.Context()
+	inv := open.inventory
+	keeper, _ := withConditionsInMemory(t)
+	told := &conditions.Told{}
+	was := doctorFrom
+	doctorFrom = &doctor{open: open, keeper: keeper, teller: told}
+	t.Cleanup(func() { doctorFrom = was })
+	wasSend := sendRollout
+	var sent [][]string
+	sendRollout = func(ctx context.Context, open *stores, names []string) ([]string, error) {
+		sent = append(sent, names)
+		return names, nil
+	}
+	t.Cleanup(func() { sendRollout = wasSend })
+
+	build := func(id, commit, digest string, asked time.Time) inventory.Build {
+		manifest, _ := json.Marshal(catalogue.Manifest{Module: "mesh-controller", Version: commit})
+		b := inventory.Build{ID: id, Module: "mesh-controller", Commit: commit, Repository: "novox/mesh-controller", Path: ".",
+			Manifest: manifest, Asked: asked, At: asked, Made: []inventory.Artifact{{Name: "controller", Kind: catalogue.ArtifactBundle,
+				Reference: "mesh-artifact://mesh-controller/controller/blobs/sha256:" + digest}}}
+		if err := inv.RecordBuild(ctx, b); err != nil {
+			t.Fatal(err)
+		}
+		if err := inv.RegisterModule(ctx, catalogue.Manifest{Module: "mesh-controller", Version: commit},
+			inventory.Source{Repository: "novox/mesh-controller", Seat: "git", Path: ".", BuiltFrom: commit, Head: commit, Asked: asked}); err != nil {
+			t.Fatal(err)
+		}
+		return b
+	}
+	previous := build("build-old", "ef26d4cb", strings.Repeat("1", 64), time.Now().Add(-2*time.Hour))
+	failed := build("build-new", "e6b00e2e", strings.Repeat("2", 64), time.Now().Add(-time.Minute))
+	if versionOfBuild(previous) != strings.Repeat("1", 12) {
+		t.Fatalf("the build's version is %q", versionOfBuild(previous))
+	}
+	applied, err := inv.SchemaApplied(ctx)
+	if err != nil || applied < 87 {
+		t.Fatalf("the store's schema reaches %d (%v)", applied, err)
+	}
+	// The build before never recorded what it reads: not proved, refused.
+	if why, ok := controllerSchemaAllows(ctx, inv, previous); ok || !strings.Contains(why, "never recorded") {
+		t.Fatalf("an unknown reach: %v %q", ok, why)
+	}
+	// It reads less than the store has: refused, naming both.
+	if err := inv.RecordSchemaReach(ctx, versionOfBuild(previous), applied-1); err != nil {
+		t.Fatal(err)
+	}
+	if why, ok := controllerSchemaAllows(ctx, inv, previous); ok || !strings.Contains(why, "is at") {
+		t.Fatalf("a reach behind the store: %v %q", ok, why)
+	}
+	// Through the gate: the failed build is marked, nothing is put back, nothing is sent, the condition is urgent.
+	at := time.Now().Add(-5 * time.Minute)
+	state := &inventory.PlanModule{Build: failed.ID, Commit: failed.Commit, Previous: previous.Commit, First: []string{"anchor"}, FirstAt: &at}
+	p := inventory.Plan{ID: "plan-352", Repository: "novox/mesh-controller", Branch: "main", Commit: failed.Commit, Created: at,
+		State: inventory.PlanRolling, Tiers: [][]string{{"mesh-controller"}}, Modules: map[string]*inventory.PlanModule{"mesh-controller": state}}
+	if err := inv.SavePlan(ctx, &p); err != nil {
+		t.Fatal(err)
+	}
+	gateFailed(ctx, open, &p, "mesh-controller", state, []string{"anchor"}, "not healthy within 10m0s of its apply")
+	if state.Gate.Rollback != inventory.NotRolledBack || !strings.Contains(p.Note, "NOT put back") || !strings.Contains(p.Note, "the current build is kept") {
+		t.Fatalf("rollback %q: %s", state.Gate.Rollback, p.Note)
+	}
+	if len(sent) != 0 {
+		t.Fatalf("sent %v: nothing is put back", sent)
+	}
+	if current, _ := inv.CurrentBuilds(ctx); current["mesh-controller"].Commit != failed.Commit {
+		t.Fatalf("the module was put back to %s", current["mesh-controller"].Commit)
+	}
+	if marked, _ := inv.GateFailed(ctx, failed.ID); !marked {
+		t.Fatal("the failed build is not marked failed at its gate")
+	}
+	open2, _ := keeper.Open(ctx)
+	var found bool
+	for _, c := range open2 {
+		if c.Kind == kindRollbackFailed && c.Severity == conditions.Urgent && strings.Contains(c.Summary, "current build is kept") {
+			found = true
+		}
+	}
+	if !found {
+		t.Fatalf("no urgent rollback-failed condition saying the current build is kept: %+v", open2)
+	}
+	// Reaching the store: allowed.
+	if err := inv.RecordSchemaReach(ctx, versionOfBuild(previous), applied); err != nil {
+		t.Fatal(err)
+	}
+	if why, ok := controllerSchemaAllows(ctx, inv, previous); !ok {
+		t.Fatalf("a build that reads the whole schema was refused: %q", why)
+	}
+	// A build with no bundle to know it by: refused.
+	if why, ok := controllerSchemaAllows(ctx, inv, inventory.Build{Commit: "x"}); ok || !strings.Contains(why, "names no bundle") {
+		t.Fatalf("a build without a bundle: %v %q", ok, why)
+	}
+}
+
+// The lease's holder names the build the declaration told it it is, and the version stamp only without one.
+func TestTheHolderNamesTheBuildTheDeclarationToldIt(t *testing.T) {
+	t.Setenv(RunningBuildVar, " ad62528c47c7 ")
+	if h := holderOf("x"); h.Build != "ad62528c47c7" {
+		t.Fatalf("the holder's build is %q", h.Build)
+	}
+	t.Setenv(RunningBuildVar, "")
+	if h := holderOf("x"); h.Build != version {
+		t.Fatalf("without a declared version the holder's build is %q", h.Build)
+	}
+	if reach, err := schemaReach(); err != nil || reach < 87 {
+		t.Fatalf("this build's reach is %d (%v)", reach, err)
+	}
+}

cmd/mesh-controller/push.go

@@ -76,6 +76,21 @@ func serve(ctx context.Context) (err error) {
 	}
 	defer open.Close()
 	inv := open.inventory
+	// **What this build reads of the store's schema, on record** (novox/hq issue 352): the highest migration
+	// it carries, by its version, so a gate that would put this build back later knows it reads the store
+	// as it is then. A build that does not know its version records nothing, and is never put back.
+	if build := runningBuild(); build != "" {
+		if reach, err := schemaReach(); err != nil {
+			fmt.Printf("what this build reads of the store's schema is not recorded: %v\n", err)
+		} else if err := inv.RecordSchemaReach(ctx, build, reach); err != nil {
+			fmt.Printf("what this build (%s) reads of the store's schema is not recorded: %v\n", build, err)
+		} else {
+			fmt.Printf("this build (%s) reads the store's schema up to migration %04d; recorded\n", build, reach)
+		}
+	} else {
+		fmt.Printf("this process was not told which build it is (%s), so what it reads of the store's schema is not "+
+			"recorded, and a gate will never put it back\n", RunningBuildVar)
+	}
 
 	ident, err := openIdentity(ctx)
 	if err != nil {
@@ -1598,3 +1613,18 @@ func reportUnheldPushed(w io.Writer, named bool, asked []string, unheld map[stri
 		fmt.Fprintf(w, "%s: %d unmet seat dependenc(ies) — see `status`\n", node, len(lines))
 	}
 }
+
+// schemaReach is the highest migration this build carries for the inventory's store (novox/hq issue 352).
+func schemaReach() (int, error) {
+	migrations, err := inventory.Migrations()
+	if err != nil {
+		return 0, err
+	}
+	reach := 0
+	for _, m := range migrations {
+		if m.Number > reach {
+			reach = m.Number
+		}
+	}
+	return reach, nil
+}

cmd/mesh-controller/release.go

@@ -180,12 +180,35 @@ func (f moveFacts) moves(node string, modules []string, sent map[string]string,
 	return out
 }
 
-// walkedBy is the open plan that has started walking a module's build — sent it to a first machine,
-// not yet passed — other than to this machine; empty when none does.
-func (f moveFacts) walkedBy(module, node string) string {
+// walkedBy is the open plan that has started walking a module's build — sent it to a first machine, not
+// yet passed — and whose walk this move would cross; empty when none does. A move of the same build to a
+// machine that plan already sent it is not a crossing: the build is there. A move of **another** build of
+// the module to that machine is (novox/hq issue 352): on 2026-10-09 a merge's plan sent the control node a
+// newer controller while a release's gate was judging the controller there, the release's gate read the
+// machine's report against the newer send, failed three builds and put them back under the new plan's
+// feet. A release keeps no module records: its open gate's carried moves are its walk.
+func (f moveFacts) walkedBy(module, node, to string) string {
 	for _, p := range f.plans {
+		if !p.Open() {
+			continue
+		}
+		if p.Release != nil {
+			g := p.Release.Gate
+			if g == nil || g.Verdict != "" {
+				continue
+			}
+			for _, c := range g.Carried {
+				if c.Module == module && !(slices.Contains(g.Machines, node) && sameCommit(c.To, to)) {
+					return p.ID
+				}
+			}
+			continue
+		}
 		s, holds := p.Modules[module]
-		if !p.Open() || !holds || s == nil || s.FirstAt == nil || s.SentAt != nil || slices.Contains(s.First, node) {
+		if !holds || s == nil || s.FirstAt == nil || s.SentAt != nil {
+			continue
+		}
+		if slices.Contains(s.First, node) && sameCommit(s.Commit, to) {
 			continue
 		}
 		if s.Gate != nil && s.Gate.Verdict == inventory.GatePassed {
@@ -277,11 +300,19 @@ func gatedSend(ctx context.Context, open *stores, node string, owns []inventory.
 		if own(mv.Module) {
 			continue
 		}
-		if id := f.walkedBy(mv.Module, node); id != "" {
+		if id := f.walkedBy(mv.Module, node, mv.To); id != "" {
 			return nil, nil, fmt.Errorf("%w: %s's build %s waits on %s, which %s is walking", errWalkedElsewhere,
 				mv.Module, short(mv.To), node, id)
 		}
 	}
+	// **And the plan's own modules wait too** (novox/hq issue 352): a walk of the same module by another
+	// plan, or a release, on this machine is not crossed with a newer build; this send waits for its gate.
+	for _, o := range owns {
+		if id := f.walkedBy(o.Module, node, o.To); id != "" {
+			return nil, nil, fmt.Errorf("%w: %s's build %s waits on %s, which %s is walking", errWalkedElsewhere,
+				o.Module, short(o.To), node, id)
+		}
+	}
 	for _, o := range owns {
 		i := slices.IndexFunc(moves, func(mv inventory.CarriedMove) bool { return mv.Module == o.Module })
 		switch {
@@ -526,7 +557,7 @@ func waitingMoves(ctx context.Context, open *stores, all bool) (map[string][]inv
 			return nil, err
 		}
 		for _, mv := range moves {
-			if f.walkedBy(mv.Module, n.Name) == "" {
+			if f.walkedBy(mv.Module, n.Name, mv.To) == "" {
 				out[n.Name] = append(out[n.Name], mv)
 			}
 		}
@@ -658,7 +689,7 @@ func advanceRelease(ctx context.Context, open *stores, p *inventory.Plan) (bool,
 				r.Next++
 				continue
 			}
-			r.Gate = &inventory.PlanGate{Machines: sent, Since: &now, Carried: moves}
+			r.Gate = &inventory.PlanGate{Machines: sent, Since: &now, Carried: moves, Sent: sentNow(ctx, open.inventory, sent)}
 			p.Note = fmt.Sprintf("sent %s %d build(s) that waited for a gate; judging them there", node, len(moves))
 			if said := recreationsSaid(moves); said != "" {
 				p.Note += "; " + said
@@ -693,6 +724,15 @@ func advanceRelease(ctx context.Context, open *stores, p *inventory.Plan) (bool,
 		r.Next++
 		r.Gate = nil
 		return true, nil
+	case inventory.GateSuperseded:
+		// Another send moved a judged module on the judged machine (novox/hq issue 352): no verdict on what
+		// was carried, nothing put back, and this release ends; the builds still waiting are released again
+		// by the next pass, judged afresh.
+		p.State = inventory.PlanSuperseded
+		p.Note = fmt.Sprintf("superseded on %s: %s — nothing judged, nothing put back; what still waits is released again",
+			strings.Join(g.Machines, ", "), g.Why)
+		fmt.Printf("%s: %s\n", p.ID, p.Note)
+		return true, nil
 	}
 	p.Note = ""
 	batched, back := batchingRollbacks(ctx)

cmd/mesh-controller/release_plan.go

@@ -793,6 +793,15 @@ func advanceOnce(ctx context.Context, open *stores, p *inventory.Plan,
 			case inventory.GateFailed:
 				failFirstSend(ctx, open, p, m, state, state.Gate.Machines, state.Gate.Why, step.rest)
 				return true, nil
+			case inventory.GateSuperseded:
+				// Another send moved this module on its first machine (novox/hq issue 352): the build is not
+				// judged, not marked, not put back; the plan ends here, said, and a newer plan carries on.
+				state.Why = "superseded: " + state.Gate.Why
+				p.State = inventory.PlanSuperseded
+				p.Note = fmt.Sprintf("%s's judging on %s was superseded: %s", m, strings.Join(state.Gate.Machines, ", "),
+					state.Gate.Why)
+				fmt.Printf("%s: %s\n", p.ID, p.Note)
+				return true, nil
 			case inventory.GatePassed:
 				if !state.Gate.Kept {
 					gatePassed(ctx, open, p, m, state)
@@ -964,6 +973,9 @@ func firstSend(ctx context.Context, open *stores, p *inventory.Plan, node string
 	}
 	now := time.Now().UTC()
 	lead := modules[0]
+	// What each machine was just sent, kept on the gate (novox/hq issue 352): its report is held against
+	// this send, whatever it is sent after.
+	sentWhat := sentNow(ctx, inv, sent)
 	for _, m := range modules {
 		s := p.Modules[m]
 		// What the first machine ran before: what a failed gate puts back (ADR 0236).
@@ -972,7 +984,7 @@ func firstSend(ctx context.Context, open *stores, p *inventory.Plan, node string
 		}
 		s.First, s.FirstAt = sent, &now
 		s.Gate = &inventory.PlanGate{Component: coreComponent(m), Machines: firstRunning(sent, runningOf[m]),
-			From: s.Previous, To: s.Commit, Since: &now}
+			From: s.Previous, To: s.Commit, Since: &now, Sent: sentWhat}
 		s.GatedBy = ""
 		if m == lead {
 			s.Gate.Carried = carried
@@ -1131,8 +1143,15 @@ func nextRollout(s inventory.PlanModule, running []string, together bool, report
 	var waiting, failed []string
 	for _, n := range s.First {
 		r, said := byNode[n]
-		// Only a report about what it was last sent says anything about this build.
-		if !said || r.At == nil || !r.Current {
+		// Only a report about what this plan sent it — or what it was sent after that — says anything about
+		// this build (novox/hq issue 352); a plan from before sends were kept on the gate reads the report
+		// against the send made last, as before.
+		reported := r.Current
+		if s.Gate != nil && s.Gate.Sent != nil {
+			sent, kept := s.Gate.Sent[n]
+			reported = kept && sent.ReportsOn(r)
+		}
+		if !said || r.At == nil || !reported {
 			waiting = append(waiting, n)
 			continue
 		}

internal/catalogue/build.go

@@ -173,11 +173,7 @@ func (m Manifest) Resolve(built []Built) (Manifest, error) {
 			// had — so re-composing a declaration moves nothing, where a commit would move the
 			// path of an identical binary and recreate everything that reads it.
 			for key, value := range filled {
-				text, isText := value.(string)
-				if !isText || !strings.Contains(text, versionRef) {
-					continue
-				}
-				filled[key] = strings.ReplaceAll(text, versionRef, versionOf(artifact.Digest))
+				filled[key] = withVersion(value, versionOf(artifact.Digest))
 			}
 		default:
 			return Manifest{}, fmt.Errorf("%s: %q is a %q, and an artifact is %q, %q, %q or %q",
@@ -189,6 +185,31 @@ func (m Manifest) Resolve(built []Built) (Manifest, error) {
 	return out, nil
 }
 
+// withVersion is a resource's value with `${version}` filled: in a string, and in each string of a map —
+// a process's env, where the controller is told which build it is (novox/hq issue 352). Anything else is
+// left as it is.
+func withVersion(value any, version string) any {
+	switch v := value.(type) {
+	case string:
+		if strings.Contains(v, versionRef) {
+			return strings.ReplaceAll(v, versionRef, version)
+		}
+	case map[string]any:
+		out := make(map[string]any, len(v))
+		for k, x := range v {
+			out[k] = withVersion(x, version)
+		}
+		return out
+	case map[string]string:
+		out := make(map[string]string, len(v))
+		for k, x := range v {
+			out[k] = strings.ReplaceAll(x, versionRef, version)
+		}
+		return out
+	}
+	return value
+}
+
 // checkBuild is the manifest's own account of what it builds.
 func (b *Build) problems(module string) []string {
 	if b == nil {

internal/catalogue/version_in_a_path_test.go

@@ -95,3 +95,28 @@ func TestAResourceWithoutAVersionReferenceIsUntouched(t *testing.T) {
 		t.Fatalf("a path naming no version became %q", path)
 	}
 }
+
+// A process's env can name the build's own version too (novox/hq issue 352): the controller is told which
+// build it is, and records what that build reads of the store's schema under it.
+func TestAProcessEnvCanNameTheBuildsOwnVersion(t *testing.T) {
+	m := Manifest{
+		Module: "mesh-controller",
+		Build:  &Build{Artifacts: []Artifact{{Name: "controller", Kind: ArtifactBundle, Language: "go", System: "arch"}}},
+		Resources: []map[string]any{{
+			"id": "controller", "type": "process", "artifact": "controller", "run": []any{"./mesh-controller", "serve"},
+			"env": map[string]any{"MESH_CONTROLLER_VERSION": "${version}", "OTHER": "kept"},
+		}},
+	}
+	got, err := m.Resolve([]Built{{Name: "controller", Kind: ArtifactBundle,
+		Reference: "artifact-store://mesh-controller/controller", Digest: aDigest}})
+	if err != nil {
+		t.Fatal(err)
+	}
+	env, _ := got.Resources[0]["env"].(map[string]any)
+	if env["MESH_CONTROLLER_VERSION"] != "ad62528c47c7" || env["OTHER"] != "kept" {
+		t.Fatalf("the env resolved to %v", env)
+	}
+	if run, _ := got.Resources[0]["run"].([]any); len(run) != 2 {
+		t.Fatalf("the run was changed: %v", run)
+	}
+}

internal/inventory/gate.go

@@ -23,6 +23,9 @@ import (
 const (
 	GatePassed = "passed"
 	GateFailed = "failed"
+	// GateSuperseded is a judging ended by a later send to the judged machine that moved the module to
+	// another build (novox/hq issue 352): no verdict on the build, and nothing put back.
+	GateSuperseded = "superseded"
 
 	RollingBack   = "rolling-back"
 	RolledBack    = "rolled-back"

internal/inventory/migrations/0087-a-controller-records-what-its-stores-schema-reaches.sql

@@ -0,0 +1,10 @@
+-- A controller records, when it serves, how far the store's schema reaches in the build it is (novox/hq
+-- issue 352): the highest migration it carries, by its build's version. A gate that fails the controller's
+-- build puts the build before it back, and on 2026-10-09 that build was older than the migrations the
+-- failed one had applied: it started, said it was behind its own row, and judged the next gate half-blind.
+-- A put-back now reads this and keeps the current build when the one before it reaches less than the store.
+create table controller_schema (
+    build    text        primary key,
+    reach    integer     not null,
+    recorded timestamptz not null default now()
+);

internal/inventory/nodes.go

@@ -1054,13 +1054,57 @@ type Reported struct {
 	// acted on the current words, not merely spoken after they were written. False also covers
 	// a machine that has not said which, which is every host from before reports carried it.
 	Current bool
+	// Declared is the digest of the declaration the last report was about, and ReportedSequence that
+	// declaration's sequence as the report claimed it (zero from an engine that claims none): what a
+	// gate holds against the send it made, rather than against the send made last (novox/hq issue 352).
+	Declared         string
+	ReportedSequence int64
+}
+
+// SentDeclaration is what one send carried to a machine, as a gate keeps it: the declaration's digest and
+// its sequence (novox/hq issue 352). A report about this declaration, or about one sequenced after it, is a
+// report on what the gate sent — whatever the machine was sent since.
+type SentDeclaration struct {
+	Digest   string `json:"digest"`
+	Sequence int64  `json:"sequence,omitempty"`
+}
+
+// ReportsOn says a report is about this send: the declaration itself; one the same machine was sequenced
+// after it; or the declaration the machine was sent last (Current), which is this send or a later one —
+// sends to a machine are made one after another. A send kept without a sequence is matched by its digest
+// and by the last send alone.
+func (s SentDeclaration) ReportsOn(r Reported) bool {
+	if r.Current || (s.Digest != "" && r.Declared == s.Digest) {
+		return true
+	}
+	return s.Sequence > 0 && r.ReportedSequence >= s.Sequence
+}
+
+// SentTo is the declaration a machine was last sent, by name: its digest and sequence, and false when it
+// was never sent one.
+func (i *Inventory) SentTo(ctx context.Context, name string) (SentDeclaration, bool, error) {
+	var digest *string
+	var seq *int64
+	err := i.store.Pool().QueryRow(ctx, `select sent, sequence from node where name = $1`, name).Scan(&digest, &seq)
+	if errors.Is(err, pgx.ErrNoRows) {
+		return SentDeclaration{}, false, fmt.Errorf("%w: %s", ErrNoSuchNode, name)
+	}
+	if err != nil || digest == nil || *digest == "" {
+		return SentDeclaration{}, false, err
+	}
+	s := SentDeclaration{Digest: *digest}
+	if seq != nil {
+		s.Sequence = *seq
+	}
+	return s, true, nil
 }
 
 // LastReports is every machine's last report beside when it was last sent a declaration.
 func (i *Inventory) LastReports(ctx context.Context) ([]Reported, error) {
 	rows, err := i.store.Pool().Query(ctx,
 		`select n.name, coalesce(r.outcome, ''), r.at, n.sent_at,
-		        r.declared is not null and r.declared <> '' and r.declared = n.sent
+		        r.declared is not null and r.declared <> '' and r.declared = n.sent,
+		        coalesce(r.declared, ''), coalesce(r.reported_sequence, 0)
 		 from node n left join node_report r on r.node = n.id
 		 order by n.name`)
 	if err != nil {
@@ -1070,7 +1114,7 @@ func (i *Inventory) LastReports(ctx context.Context) ([]Reported, error) {
 	var out []Reported
 	for rows.Next() {
 		var r Reported
-		if err := rows.Scan(&r.Node, &r.Outcome, &r.At, &r.Sent, &r.Current); err != nil {
+		if err := rows.Scan(&r.Node, &r.Outcome, &r.At, &r.Sent, &r.Current, &r.Declared, &r.ReportedSequence); err != nil {
 			return nil, err
 		}
 		out = append(out, r)

internal/inventory/plans.go

@@ -126,6 +126,10 @@ type PlanGate struct {
 	To        string   `json:"to,omitempty"`
 	// Since is when the judging began: the first machine reported the new build applied.
 	Since *time.Time `json:"since,omitempty"`
+	// Sent is, per machine, the declaration the gate's send carried there (novox/hq issue 352): what a
+	// machine's report is held against. Absent on a gate kept before it was, which reads the report
+	// against the send made last, as before.
+	Sent map[string]SentDeclaration `json:"sent,omitempty"`
 	// Passes counts the consecutive judgings that found it healthy, LastPass the newest; a judging that
 	// does not resets them.
 	Passes   int        `json:"passes,omitempty"`

internal/inventory/plans_test.go

@@ -115,3 +115,83 @@ func TestTheNewestMergeOfABranchIsTheOneMergedLast(t *testing.T) {
 		t.Fatalf("one merge time, two plans: %s", p.ID)
 	}
 }
+
+// novox/hq issue 352: what a machine was last sent is read back by name with its sequence, a report keeps
+// the declaration it was about and that declaration's sequence, and a gate's sends are kept with the plan.
+func TestASendAndAReportAreKnownByTheirDeclaration(t *testing.T) {
+	inv := ForTest(t)
+	ctx := t.Context()
+	record, err := inv.AddNode(ctx, "anchor")
+	if err != nil {
+		t.Fatal(err)
+	}
+	if _, found, err := inv.SentTo(ctx, "anchor"); err != nil || found {
+		t.Fatalf("a machine never sent anything: %v %v", found, err)
+	}
+	if _, _, err := inv.SentTo(ctx, "nobody"); err == nil {
+		t.Fatal("a machine that does not exist was answered")
+	}
+	seq, err := inv.NextSequence(ctx, record.ID)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if err := inv.RecordSent(ctx, record.ID, "d-1", map[string]string{"app": "c1"}); err != nil {
+		t.Fatal(err)
+	}
+	sent, found, err := inv.SentTo(ctx, "anchor")
+	if err != nil || !found || sent.Digest != "d-1" || sent.Sequence != seq {
+		t.Fatalf("sent %+v %v %v", sent, found, err)
+	}
+	if _, err := inv.RecordOrderedDoing(ctx, record.ID, Doing{Node: "anchor", Outcome: OutcomeApplied, Declared: "d-1", Applied: 1},
+		ReportOrder{Sequence: seq, ReportSequence: 1}, func(ReportOrder) bool { return false }); err != nil {
+		t.Fatal(err)
+	}
+	reports, err := inv.LastReports(ctx)
+	if err != nil || len(reports) != 1 || reports[0].Declared != "d-1" || reports[0].ReportedSequence != seq || !reports[0].Current {
+		t.Fatalf("reports %+v %v", reports, err)
+	}
+	// Sent again, unreported: the report is no longer on the last send, and is still on the first.
+	if err := inv.RecordSent(ctx, record.ID, "d-2", map[string]string{"app": "c1"}); err != nil {
+		t.Fatal(err)
+	}
+	reports, _ = inv.LastReports(ctx)
+	if reports[0].Current || !sent.ReportsOn(reports[0]) {
+		t.Fatalf("after a newer send: %+v", reports[0])
+	}
+	at := time.Now().UTC()
+	p := Plan{ID: "plan-352", Repository: "novox/x", Commit: "c", Created: at, State: PlanRolling, Tiers: [][]string{{"app"}},
+		Modules: map[string]*PlanModule{"app": {Gate: &PlanGate{Machines: []string{"anchor"}, Since: &at,
+			Sent: map[string]SentDeclaration{"anchor": sent}}}}}
+	if err := inv.SavePlan(ctx, &p); err != nil {
+		t.Fatal(err)
+	}
+	kept, err := inv.PlanByID(ctx, "plan-352")
+	if err != nil || kept.Modules["app"].Gate.Sent["anchor"] != sent {
+		t.Fatalf("the gate's send was not kept with the plan: %+v %v", kept.Modules["app"].Gate, err)
+	}
+}
+
+// A controller build's reach of the store's schema is kept by its version, and the store's own is read.
+func TestASchemaReachIsKeptByBuild(t *testing.T) {
+	inv := ForTest(t)
+	ctx := t.Context()
+	applied, err := inv.SchemaApplied(ctx)
+	if err != nil || applied < 87 {
+		t.Fatalf("applied %d %v", applied, err)
+	}
+	if _, known, err := inv.SchemaReachOf(ctx, "ad62528c47c7"); err != nil || known {
+		t.Fatalf("an unrecorded build: %v %v", known, err)
+	}
+	if err := inv.RecordSchemaReach(ctx, "", 87); err == nil {
+		t.Fatal("a reach without a build was recorded")
+	}
+	if err := inv.RecordSchemaReach(ctx, "ad62528c47c7", 86); err != nil {
+		t.Fatal(err)
+	}
+	if err := inv.RecordSchemaReach(ctx, "ad62528c47c7", 87); err != nil {
+		t.Fatal(err)
+	}
+	if reach, known, err := inv.SchemaReachOf(ctx, "ad62528c47c7"); err != nil || !known || reach != 87 {
+		t.Fatalf("reach %d %v %v", reach, known, err)
+	}
+}

internal/inventory/schema.go

@@ -0,0 +1,47 @@
+package inventory
+
+import (
+	"context"
+	"errors"
+
+	"github.com/jackc/pgx/v5"
+)
+
+// What a controller build knows of the store's schema (novox/hq issue 352): the highest migration it
+// carries, recorded by its version when it serves, and the highest migration the store has applied. A
+// put-back of the controller to a build that reaches less than the store is refused (gate.go), because
+// such a controller starts behind its own records and judges with what it can read.
+
+// RecordSchemaReach keeps the highest migration the build serving now carries.
+func (i *Inventory) RecordSchemaReach(ctx context.Context, build string, reach int) error {
+	if build == "" {
+		return errors.New("a schema reach is recorded by a build's version, and this controller has none")
+	}
+	_, err := i.store.Pool().Exec(ctx,
+		`insert into controller_schema (build, reach) values ($1, $2)
+		 on conflict (build) do update set reach = excluded.reach, recorded = now()`, build, reach)
+	return err
+}
+
+// SchemaReachOf is the highest migration a build carries, as it recorded when it served; false for a
+// build that never did.
+func (i *Inventory) SchemaReachOf(ctx context.Context, build string) (int, bool, error) {
+	var reach int
+	err := i.store.Pool().QueryRow(ctx, `select reach from controller_schema where build = $1`, build).Scan(&reach)
+	if errors.Is(err, pgx.ErrNoRows) {
+		return 0, false, nil
+	}
+	return reach, err == nil, err
+}
+
+// SchemaApplied is the highest migration the store has applied.
+func (i *Inventory) SchemaApplied(ctx context.Context) (int, error) {
+	var n *int
+	if err := i.store.Pool().QueryRow(ctx, `select max(number) from migration`).Scan(&n); err != nil {
+		return 0, err
+	}
+	if n == nil {
+		return 0, nil
+	}
+	return *n, nil
+}

module.json

@@ -118,7 +118,8 @@
         "MESH_STORE_LICENCES_PORT": "${seat:mesh-store:5432}",
         "MESH_BROKER_MANAGEMENT_PORT": "${seat:mesh-broker:15672}",
         "MESH_BROKER_ADDRESS_PORT": "${seat:mesh-broker:5671}",
-        "MESH_BUS_NATS_FILE": "${dir:mesh-state}/bus"
+        "MESH_BUS_NATS_FILE": "${dir:mesh-state}/bus",
+        "MESH_CONTROLLER_VERSION": "${version}"
       },
       "replaces": [
         "server"