v0.122.0: three ways the signals lied about themselves (R-189, R-188, R-186)

All three are the reporting and release path misreporting its own work. No
customer machine, no backup, no restore, no data. The restore-test itself and
when it runs are unchanged.

R-189 — a passing restore-test no longer vanishes on a restart. restore_tests[]
came only from the in-memory store, whose comment ("lost on restart; the cadence
re-populates") was true under a timer and stopped being true when R-86 made the
agent refuse to re-test a proven archive: the proof is then not repeated for a
whole archive generation. Observed live — a 14.5 GB offsite PASS reached no
host-report because the agent was restarted 2m43s later. RestoreTestState now
carries tier + verified beside the archive and renders reportable entries; the
collector merges them, one per tier, newest by TestedAt. It refuses to lie: a
record missing archive-or-tier produces no entry, and run mechanics are not
re-invented. Only successes are persisted, and the asymmetry is now written where
it will be read.

R-188 — a correct release stops emailing a failure. Only the tag PUSH moved
(build -> tag locally -> publish -> push tag): the push wakes CI, and a tag
visible before its package made the gate correctly fail a correct release about
half the time. The old order's invariant is asserted directly instead — the gate
now refuses a published version with no tag, as a bounded probe that prints its
own coverage, because the package listing api is still 401 without a token.

R-186 — a released binary can be verified by rebuilding it. -trimpath
-buildvcs=false: same source, same bytes, tag or no tag. Measured. publish-agent's
fallback also forced CGO_ENABLED=0 and produced a 74 KB different binary for the
same version; both paths now build identically. CLAUDE.md records the command.

internal/backup/restoretest_due_test.go

@@ -442,7 +442,7 @@ func TestRestoreTestState_ArchiveRoundTrips(t *testing.T) {
 	path := filepath.Join(t.TempDir(), "rt.json")
 	now := time.Now().UTC().Truncate(time.Second)
 	st := NewRestoreTestState(path)
-	if err := st.RecordSuccess("felhom-pbs", "felhom-pbs:backup/ct/9201/x", now); err != nil {
+	if err := st.RecordSuccess("felhom-pbs", "felhom-pbs:backup/ct/9201/x", "pbs", "boot+running", now); err != nil {
 		t.Fatal(err)
 	}
 	re := NewRestoreTestState(path)
@@ -475,7 +475,7 @@ func TestDue_NothingDueStillNamesEveryTiersVerdict(t *testing.T) {
 	}}
 	h := newDueHarness(t, day0.AddDate(0, 0, 1), 24*time.Hour, true, []string{"local", "felhom-pbs"}, ts)
 	// Prove the local tier so NOTHING is due.
-	if err := h.st.RecordSuccess("local", "local:backup/a.tar.zst", h.clock); err != nil {
+	if err := h.st.RecordSuccess("local", "local:backup/a.tar.zst", "local", "boot+running", h.clock); err != nil {
 		t.Fatal(err)
 	}
 
@@ -505,3 +505,89 @@ func TestDue_VerdictSummaryNamesAnUnknownTier(t *testing.T) {
 		t.Fatalf("an unlistable tier must read as UNKNOWN with its error; got %q", got)
 	}
 }
+
+// ── R-189 — the persisted proof must be REPORTABLE, and must refuse to lie ───────────────────
+//
+// A proof held only in the in-memory store dies with the process, and under per-archive due-ness the
+// agent will not repeat the work. So the persisted record has to be able to become a host-report
+// entry — without inventing anything it does not know.
+//
+// COMPANION RED-PROOF (observed 2026-08-03): drop the `reportable()` filter from
+// ProvenRestoreTests, so a pre-R-189 record (archive but no tier) is emitted →
+//
+//	--- FAIL: TestProvenRestoreTests_RefusesToReportWhatItCannotDescribe
+//	    restoretest_due_test.go: a record with no TIER must not be reported (the hub keys its
+//	    per-tier proof on it); got [{... SourceTier: ...}]
+//
+// Restored.
+func TestProvenRestoreTests_RefusesToReportWhatItCannotDescribe(t *testing.T) {
+	path := filepath.Join(t.TempDir(), "rt.json")
+	// v1 (a bare time), v2 (archive, no tier) and v3 (complete) side by side — every shape this
+	// file has ever had, which is what a real box carries after two upgrades.
+	legacy := `{
+	  "old-v1":     "2026-07-30T02:11:07Z",
+	  "old-v2":     {"archive":"felhom-backup:backup/vzdump-lxc-9201-a.tar.zst","proven_at":"2026-08-01T04:41:58Z"},
+	  "felhom-pbs": {"archive":"felhom-pbs:backup/ct/9201/2026-07-28T04:49:43Z","tier":"pbs","verified":"boot+running","proven_at":"2026-08-03T13:25:14Z"}
+	}`
+	if err := writeFileForTest(path, legacy); err != nil {
+		t.Fatal(err)
+	}
+
+	got := NewRestoreTestState(path).ProvenRestoreTests(context.Background())
+	if len(got) != 1 {
+		t.Fatalf("only the record that can be described honestly may be reported; got %d: %+v", len(got), got)
+	}
+	e := got[0]
+	if e.SourceTier != "pbs" {
+		t.Fatalf("a record with no TIER must not be reported (the hub keys its per-tier proof on it); got %+v", got)
+	}
+	if e.SourceArchive != "felhom-pbs:backup/ct/9201/2026-07-28T04:49:43Z" || !e.Pass {
+		t.Fatalf("the reported entry must be the stored proof, unchanged; got %+v", e)
+	}
+	if e.TestedAt != "2026-08-03T13:25:14Z" {
+		t.Fatalf("the entry must carry the time the run passed, not now(); got %q", e.TestedAt)
+	}
+	if e.Verified != "boot+running" {
+		t.Fatalf("what the run verified must survive the round trip; got %q", e.Verified)
+	}
+	// Run mechanics are NOT invented: an absent duration is not a claim, a fabricated one would be.
+	if e.DurationSeconds != 0 || e.ScratchVMID != 0 {
+		t.Fatalf("the re-report must not invent run mechanics it never stored; got duration=%v scratch=%d",
+			e.DurationSeconds, e.ScratchVMID)
+	}
+	// The legacy records still serve the DUE-check, which is a separate question from reporting.
+	if _, ok := NewRestoreTestState(path).ProvenArchive("old-v2"); !ok {
+		t.Fatal("a v2 record must still answer the due-check even though it cannot be reported")
+	}
+}
+
+// A tier proved through the SCHEDULER (not by hand) lands in the state complete enough to report —
+// the production path, not a hand-built fixture.
+func TestScheduler_ProofIsRecordedReportably(t *testing.T) {
+	ts := &tierStorage{archives: map[string][]archiveStub{"felhom-pbs": {{volid: "felhom-pbs:backup/ct/9201/w0", landed: day0}}}}
+	h := newDueHarness(t, day0.AddDate(0, 0, 1).Add(97*time.Minute), 24*time.Hour, true, []string{"felhom-pbs"}, ts)
+	// The fake runner echoes the spec's tier; give the spec a tier the way main.go does.
+	h.s.spec = func(_ context.Context, archive string) reconcile.RestoreTestSpec {
+		return reconcile.RestoreTestSpec{RestoreStorage: "local-lvm", ScratchMin: 990000, ScratchMax: 990009, SourceTier: "pbs"}
+	}
+	h.s.tick(context.Background())
+
+	got := h.st.ProvenRestoreTests(context.Background())
+	if len(got) != 1 {
+		t.Fatalf("a scheduled pass must leave a REPORTABLE proof; got %d: %+v", len(got), got)
+	}
+	if got[0].SourceTier != "pbs" || got[0].SourceArchive != "felhom-pbs:backup/ct/9201/w0" {
+		t.Fatalf("the proof must name the tier and the archive the run used; got %+v", got[0])
+	}
+}
+
+// A FAILED run leaves nothing to report — the asymmetry of §8.1, asserted rather than assumed.
+func TestScheduler_AFailureLeavesNoPersistedProof(t *testing.T) {
+	ts := &tierStorage{archives: map[string][]archiveStub{"felhom-pbs": {{volid: "felhom-pbs:backup/ct/9201/w0", landed: day0}}}}
+	h := newDueHarness(t, day0.AddDate(0, 0, 1).Add(97*time.Minute), 24*time.Hour, false, []string{"felhom-pbs"}, ts)
+	h.s.tick(context.Background())
+	if got := h.st.ProvenRestoreTests(context.Background()); len(got) != 0 {
+		t.Fatalf("a FAILED run must persist nothing — a failing tier is retried, and a stored failure "+
+			"would outlive the fault; got %+v", got)
+	}
+}

internal/backup/restoretest_state.go

@@ -1,12 +1,15 @@
 package backup
 
 import (
+	"context"
 	"encoding/json"
 	"os"
 	"path/filepath"
 	"sort"
 	"sync"
 	"time"
+
+	"gitea.dooplex.hu/admin/felhom-agent/internal/hub"
 )
 
 // RestoreTestState persists the last SUCCESSFUL restore-test per backup tier.
@@ -49,16 +52,45 @@ type RestoreTestState struct {
 	last map[string]provenTier // target id → what was last PROVEN on that tier
 }
 
-// provenTier is one tier's proof: the archive that passed, and when it passed.
+// provenTier is one tier's proof: the archive that passed, which tier it was, what was verified,
+// and when.
+//
+// R-189 added `Tier` and `Verified`. Until then this record could answer the DUE-check but could not
+// be REPORTED, and being reportable is what closes R-189: a proof held only in the in-memory result
+// store vanishes on restart, and under per-archive due-ness the box will not repeat the work, so the
+// hub can stay ignorant of a real success until the next archive generation.
+//
+// `Tier` is stored rather than derived because it is known for certain at proof time (the run's own
+// spec used it to choose the restore timeout) and deriving it later would need a storage-type lookup
+// at report-building time — a network call that can fail, on a path where failing means mis-labelling
+// a proof. Store what you knew when you knew it.
 type provenTier struct {
-	Archive string    // volid of the archive that PASSED; "" = a legacy record with no archive
-	At      time.Time // when that run passed (UTC)
+	Archive  string    // volid of the archive that PASSED; "" = a legacy record with no archive
+	Tier     string    // "local" | "pbs" — as the run reported it; "" = pre-R-189 record
+	Verified string    // what the run verified (e.g. "boot+running"); "" = pre-R-189 record
+	At       time.Time // when that run passed (UTC)
 }
 
-// provenTierJSON is the on-disk shape (R-86). The legacy shape was a bare RFC3339 STRING per
-// target; both are read, only this one is written — see NewRestoreTestState.
+// reportable reports whether this record can be re-reported to the hub as a restore-test result.
+//
+// It needs BOTH the archive and the tier: the hub keys its edge-triggered failure state on the
+// archive and its per-tier proof lookup on the tier, so an entry missing either is not a usable
+// proof — and emitting one anyway would be a report the hub cannot act on, dressed as evidence.
+// A pre-R-189 record is therefore silently not reported; the tier's next real proof fills it in.
+func (p provenTier) reportable() bool { return p.Archive != "" && p.Tier != "" }
+
+// provenTierJSON is the on-disk shape. Two older shapes are read and neither is written:
+//
+//	v1 (pre-R-86)  "<target>": "<RFC3339>"                     — a time, no archive
+//	v2 (R-86)      "<target>": {archive, proven_at}            — due-check usable, not reportable
+//	v3 (R-189)     "<target>": {archive, tier, verified, …}    — both
+//
+// Fields absent in an older file unmarshal to "", which is exactly the "no usable proof" signal the
+// readers above test for — the migration needs no version number because the absence IS the answer.
 type provenTierJSON struct {
 	Archive  string `json:"archive"`
+	Tier     string `json:"tier,omitempty"`
+	Verified string `json:"verified,omitempty"`
 	ProvenAt string `json:"proven_at"`
 }
 
@@ -99,21 +131,31 @@ func NewRestoreTestState(path string) *RestoreTestState {
 		if perr != nil {
 			continue
 		}
-		s.last[target] = provenTier{Archive: cur.Archive, At: t.UTC()}
+		s.last[target] = provenTier{Archive: cur.Archive, Tier: cur.Tier, Verified: cur.Verified, At: t.UTC()}
 	}
 	return s
 }
 
-// RecordSuccess stamps a tier as proven at t, naming the ARCHIVE that passed. Only call this for a
-// PASSING restore-test — the archive is what makes the tier not-due, so recording one for a failed
-// run would retire the archive unproven.
-func (s *RestoreTestState) RecordSuccess(target, archive string, t time.Time) error {
+// RecordSuccess stamps a tier as proven at t, naming the ARCHIVE that passed, the TIER the run
+// reported, and what it verified. Only call this for a PASSING restore-test — the archive is what
+// makes the tier not-due, so recording one for a failed run would retire the archive unproven.
+//
+// ONLY SUCCESSES ARE PERSISTED, AND THE ASYMMETRY IS DELIBERATE (R-189 §8.1). Say it here because
+// the next reader will notice failures are absent and try to "fix" it:
+//
+//	a SUCCESS suppresses future work — a proven archive is never re-tested, so a lost proof leaves
+//	the system quietly less tested than it believes. It must survive a restart.
+//
+//	a FAILURE causes future work — a failing tier stays due and is retried at the next evaluation,
+//	so a lost failure heals itself within one interval. Persisting it would do the opposite of
+//	helping: a healed tier would keep reporting a failure that is no longer true.
+func (s *RestoreTestState) RecordSuccess(target, archive, tier, verified string, t time.Time) error {
 	if target == "" {
 		return nil
 	}
 	s.mu.Lock()
 	defer s.mu.Unlock()
-	s.last[target] = provenTier{Archive: archive, At: t.UTC()}
+	s.last[target] = provenTier{Archive: archive, Tier: tier, Verified: verified, At: t.UTC()}
 	return s.saveLocked()
 }
 
@@ -138,7 +180,13 @@ func (s *RestoreTestState) ProvenArchive(target string) (string, bool) {
 	return p.Archive, true
 }
 
-// Snapshot returns a copy of the last-proven TIMES — for the host-report gauge.
+// Snapshot returns a copy of the last-proven TIMES.
+//
+// It carried the comment "for the host-report gauge" from the day it was written and **had no caller
+// at all** until R-189 — a seam built and never wired, and an invariant asserted in a comment with
+// nothing pinning it, in one method. The host report is now fed by ProvenRestoreTests below, which
+// carries the archive and the tier that a bare timestamp cannot. This stays for callers that want
+// only the times; if it acquires none, delete it rather than let it claim a purpose again.
 func (s *RestoreTestState) Snapshot() map[string]time.Time {
 	s.mu.Lock()
 	defer s.mu.Unlock()
@@ -149,6 +197,41 @@ func (s *RestoreTestState) Snapshot() map[string]time.Time {
 	return out
 }
 
+// ProvenRestoreTests renders the persisted proofs as host-report entries — the R-189 fix.
+//
+// It satisfies hub.RestoreTestReporter's shape, so the collector can merge these with the in-memory
+// results. What it emits is a RE-REPORT of a run that really happened, not a synthesis:
+//
+//   - `Pass` is true because ONLY successes are stored (RecordSuccess is the sole writer);
+//   - `SourceArchive`, `SourceTier`, `Verified` and `TestedAt` are the values that run reported;
+//   - the run mechanics (scratch VMID, duration, warnings) are NOT re-invented. An absent duration
+//     is not a claim; a fabricated one would be.
+//
+// A record that cannot be reported honestly is omitted rather than padded — see provenTier.reportable.
+// **A tier with no usable proof produces NO entry**: an unproven tier reading as proven would be a
+// worse defect than the one this fixes.
+func (s *RestoreTestState) ProvenRestoreTests(context.Context) []hub.RestoreTest {
+	s.mu.Lock()
+	defer s.mu.Unlock()
+	out := make([]hub.RestoreTest, 0, len(s.last))
+	for _, p := range s.last {
+		if !p.reportable() {
+			continue
+		}
+		out = append(out, hub.RestoreTest{
+			SourceArchive: p.Archive,
+			SourceTier:    p.Tier,
+			Pass:          true,
+			Verified:      p.Verified,
+			TestedAt:      p.At.UTC().Format(time.RFC3339),
+		})
+	}
+	// Deterministic order: the report is compared byte-wise by the contract test, and Go's map
+	// iteration is randomised.
+	sort.Slice(out, func(i, j int) bool { return out[i].SourceTier < out[j].SourceTier })
+	return out
+}
+
 // OldestFirst orders targets by "least recently proven first"; never-proven sorts FIRST.
 //
 // This is the operator's 2026-07-26 ruling (Option 1): self-balancing, no new config knob, and it
@@ -185,7 +268,10 @@ func (s *RestoreTestState) OldestFirst(targets []string) []string {
 func (s *RestoreTestState) saveLocked() error {
 	raw := make(map[string]provenTierJSON, len(s.last))
 	for target, p := range s.last {
-		raw[target] = provenTierJSON{Archive: p.Archive, ProvenAt: p.At.UTC().Format(time.RFC3339)}
+		raw[target] = provenTierJSON{
+			Archive: p.Archive, Tier: p.Tier, Verified: p.Verified,
+			ProvenAt: p.At.UTC().Format(time.RFC3339),
+		}
 	}
 	data, err := json.MarshalIndent(raw, "", "  ")
 	if err != nil {

internal/backup/rotation_test.go

@@ -303,11 +303,11 @@ func TestOldestFirst_Ordering(t *testing.T) {
 			t.Fatalf("unexpected: %v", got)
 		}
 	}
-	_ = st.RecordSuccess("local", "local:backup/a.tar.zst", now)
+	_ = st.RecordSuccess("local", "local:backup/a.tar.zst", "local", "boot+running", now)
 	if got := st.OldestFirst([]string{"local", "felhom-pbs"}); got[0] != "felhom-pbs" {
 		t.Fatalf("a never-proven tier must sort before a proven one; got %v", got)
 	}
-	_ = st.RecordSuccess("felhom-pbs", "felhom-pbs:backup/ct/9201/b", now.Add(time.Hour))
+	_ = st.RecordSuccess("felhom-pbs", "felhom-pbs:backup/ct/9201/b", "pbs", "boot+running", now.Add(time.Hour))
 	if got := st.OldestFirst([]string{"local", "felhom-pbs"}); got[0] != "local" {
 		t.Fatalf("the least recently proven must sort first; got %v", got)
 	}
@@ -318,8 +318,8 @@ func TestOldestFirst_Ordering(t *testing.T) {
 func TestOldestFirst_DeterministicOnTies(t *testing.T) {
 	st := NewRestoreTestState(filepath.Join(t.TempDir(), "rt.json"))
 	now := time.Now().UTC()
-	_ = st.RecordSuccess("b-tier", "b:archive", now)
-	_ = st.RecordSuccess("a-tier", "a:archive", now)
+	_ = st.RecordSuccess("b-tier", "b:archive", "local", "boot+running", now)
+	_ = st.RecordSuccess("a-tier", "a:archive", "local", "boot+running", now)
 	for i := 0; i < 20; i++ {
 		if got := st.OldestFirst([]string{"b-tier", "a-tier"}); got[0] != "a-tier" {
 			t.Fatalf("tie-break must be deterministic; iteration %d gave %v", i, got)
@@ -334,7 +334,7 @@ func TestRestoreTestState_PersistenceAndCorruption(t *testing.T) {
 	now := time.Now().UTC().Truncate(time.Second)
 
 	st := NewRestoreTestState(path)
-	if err := st.RecordSuccess("felhom-pbs", "felhom-pbs:backup/ct/9201/x", now); err != nil {
+	if err := st.RecordSuccess("felhom-pbs", "felhom-pbs:backup/ct/9201/x", "pbs", "boot+running", now); err != nil {
 		t.Fatal(err)
 	}
 	reopened := NewRestoreTestState(path)

internal/backup/schedule.go

@@ -218,7 +218,11 @@ func (s *Scheduler) tick(ctx context.Context) {
 	if rt.Pass && s.rtState != nil && target != "" {
 		// R-86: the ARCHIVE is recorded, not merely the time — that is what makes the tier
 		// not-due until a NEWER archive settles, and what makes a proof survive a restart.
-		if err := s.rtState.RecordSuccess(target, archive, s.now()); err != nil {
+		// R-189: the TIER and what was VERIFIED go with it, so the proof can be RE-REPORTED after a
+		// restart. Both come from the run's own result, never re-derived — `rt.SourceTier` is what
+		// this run was actually judged as, and deriving it later would need a storage lookup that
+		// can fail on the one path where failing means mislabelling a proof.
+		if err := s.rtState.RecordSuccess(target, archive, rt.SourceTier, rt.Verified, s.now()); err != nil {
 			s.logger.Warn("backup: could not persist the restore-test proof state", "target", target, "err", err)
 		}
 	}

internal/backup/store.go

@@ -10,8 +10,22 @@ import (
 // Store holds the agent's LATEST backup result per target and the latest restore-test
 // result — the point-in-time state the host-report surfaces. It is updated by the backup
 // runner + the restore-test scheduler/selftest and read by the collector via the hub
-// BackupReporter / RestoreTestReporter seams. In-memory (lost on restart; the cadence
-// re-populates) and mutex-guarded for the concurrent collector vs scheduler access.
+// BackupReporter / RestoreTestReporter seams. In-memory and mutex-guarded for the concurrent
+// collector vs scheduler access.
+//
+// **"lost on restart; the cadence re-populates" — that sentence used to be here and it is now
+// FALSE for restore-tests (R-189, 2026-08-03).** It was true while a timer re-tested every tier
+// daily. Under R-86's per-archive due-check the agent will NOT re-test an archive it has already
+// proven, so a proof lost to a restart is not repeated until the next archive generation — a week on
+// the offsite tier — and the hub reports that tier unproven throughout. Observed, not predicted: a
+// real 14.5 GB offsite restore passed, the agent was restarted 2 m 43 s later for a deploy, and two
+// consecutive host-reports carried `0 restore-tests`.
+//
+// The durable half is `RestoreTestState` (on disk, per tier, with the archive) and the collector
+// merges the two — see hub.ProvenRestoreTestReporter. This store remains the ONLY place a FAILURE is
+// recorded, and that asymmetry is deliberate: a failing tier stays due and is retried, so a lost
+// failure heals itself, while a lost success leaves the system quietly less tested than it believes.
+// Backups are unaffected — their freshness has a ground truth on the storage (R-84).
 type Store struct {
 	mu       sync.Mutex
 	byTarget map[string]hub.Backup // latest backup per target id

internal/hub/collect.go

@@ -47,6 +47,22 @@ type RestoreTestReporter interface {
 	RestoreTests(ctx context.Context) []RestoreTest
 }
 
+// ProvenRestoreTestReporter is the DURABLE half of the restore-test signal (R-189).
+//
+// RestoreTestReporter above is backed by an in-memory store whose own comment used to read "lost on
+// restart; the cadence re-populates". That was true while a timer re-tested every tier daily. It
+// stopped being true on 2026-08-03: under per-archive due-ness the agent will not re-test an archive
+// it has already proven, so a proof lost to a restart is not repeated for a whole archive generation
+// — a week on the offsite tier — and the hub reports the tier unproven the entire time.
+//
+// Observed, not predicted: a real 14.5 GB offsite restore passed at 15:25:14, the agent was restarted
+// 2 m 43 s later for a deploy, and the hub logged `0 restore-tests` on the next two reports.
+//
+// (*backup.RestoreTestState).ProvenRestoreTests satisfies this. nil → the merge is a no-op.
+type ProvenRestoreTestReporter interface {
+	ProvenRestoreTests(ctx context.Context) []RestoreTest
+}
+
 // PBSReporter is the slice-6-Phase-B seam the pbs verify loop plugs into (same pattern).
 // Returns the agent's latest-known PBS snapshot inventory + verify-state. nil → empty.
 type PBSReporter interface {
@@ -79,6 +95,7 @@ type Collector struct {
 	storage      StorageObserver
 	backups      BackupReporter
 	restoreTests RestoreTestReporter
+	provenTests  ProvenRestoreTestReporter
 	pbs          PBSReporter
 	temp         TempReader                                    // slice 9: host CPU/chassis temp (nil-safe → nil temp)
 	capProbe     func(ctx context.Context) []capability.Status // v0.44.0: privileged-capability self-check (nil → empty)
@@ -427,16 +444,90 @@ func (c *Collector) collectBackups(ctx context.Context) []Backup {
 	return []Backup{}
 }
 
+// collectRestoreTests merges the in-memory result with the PERSISTED per-tier proofs (R-189).
+//
+// The rule is ONE ENTRY PER TIER, NEWEST WINS, and it falls out of what each source means rather
+// than from a preference between them:
+//
+//   - the in-memory store holds this process's latest run, pass OR fail. A failure exists nowhere
+//     else and must always reach the hub — a failing tier is retried at the next evaluation, so its
+//     record is short-lived by design;
+//   - the persisted state holds the last SUCCESS per tier and survives a restart.
+//
+// Comparing by TestedAt gives the right answer in every case without special-casing: a fresh failure
+// beats an older stored success (the failure is the news), a stored success beats a stale in-memory
+// entry after a restart, and a tier proved twice never appears twice — two entries for one tier would
+// read at the hub as two tests.
+//
+// A tier with no usable persisted proof contributes NOTHING. Reporting an unproven tier as proven
+// would be a worse defect than the one this closes.
 func (c *Collector) collectRestoreTests(ctx context.Context) []RestoreTest {
-	if c.restoreTests == nil {
-		return []RestoreTest{}
+	out := []RestoreTest{}
+	if c.restoreTests != nil {
+		if r := c.restoreTests.RestoreTests(ctx); r != nil {
+			out = append(out, r...)
+		}
 	}
-	if r := c.restoreTests.RestoreTests(ctx); r != nil {
-		return r
+	if c.provenTests == nil {
+		return out
 	}
-	return []RestoreTest{}
+
+	// Index what we already have by tier, keeping the newest per tier.
+	best := map[string]int{} // tier → index into out
+	for i, rt := range out {
+		if rt.SourceTier == "" {
+			continue // untiered entry: never deduped, never overwritten — we cannot say what it is
+		}
+		if j, seen := best[rt.SourceTier]; !seen || newerRestoreTest(rt, out[j]) {
+			best[rt.SourceTier] = i
+		}
+	}
+	for _, p := range c.provenTests.ProvenRestoreTests(ctx) {
+		if p.SourceTier == "" {
+			continue // not usable as a per-tier proof; the state layer already filters these
+		}
+		i, seen := best[p.SourceTier]
+		if !seen {
+			out = append(out, p)
+			best[p.SourceTier] = len(out) - 1
+			continue
+		}
+		if newerRestoreTest(p, out[i]) {
+			out[i] = p
+		}
+	}
+	return out
 }
 
+// newerRestoreTest reports whether a was tested after b. An unparseable or absent timestamp is
+// treated as OLDER, so a malformed entry can never displace a good one.
+func newerRestoreTest(a, b RestoreTest) bool {
+	ta, aok := parseRestoreTestedAt(a.TestedAt)
+	tb, bok := parseRestoreTestedAt(b.TestedAt)
+	if !aok {
+		return false
+	}
+	if !bok {
+		return true
+	}
+	return ta.After(tb)
+}
+
+func parseRestoreTestedAt(s string) (time.Time, bool) {
+	t, err := time.Parse(time.RFC3339, s)
+	if err != nil {
+		return time.Time{}, false
+	}
+	return t.UTC(), true
+}
+
+// SetProvenRestoreTests wires the durable proof source. It is a setter rather than a constructor
+// argument because the persisted state is opened later in main() than the collector is built; the
+// same shape as the other late-wired seams here. **The wiring is asserted by an AST test** — the
+// method it feeds carried a doc comment naming a "host-report gauge" for weeks with no caller at
+// all, and this fix must not become the next instance of that.
+func (c *Collector) SetProvenRestoreTests(p ProvenRestoreTestReporter) { c.provenTests = p }
+
 // collectPBSSnapshots reads the latest PBS snapshot inventory via the seam (nil → empty).
 func (c *Collector) collectPBSSnapshots(ctx context.Context) []PBSSnapshot {
 	if c.pbs == nil {

internal/hub/restoretest_merge_test.go

@@ -0,0 +1,213 @@
+package hub
+
+import (
+	"context"
+	"testing"
+	"time"
+)
+
+// R-189 — a passing restore-test must survive an agent restart and reach the hub.
+//
+// THE OBSERVATION THIS EXISTS FOR (2026-08-03, demo-felhom): a real 14.5 GB offsite restore-test
+// PASSED at 15:25:14; the agent was restarted 2 m 43 s later for a deploy; the hub logged
+// `0 restore-tests` on the next two host-reports. The in-memory store's own comment said "lost on
+// restart; the cadence re-populates", which was true under a timer and stopped being true when R-86
+// made the agent refuse to re-test an archive it has already proven.
+//
+// Timestamps here carry JITTER (odd minutes and seconds, not round hours) — yesterday a test was
+// hollow because a perfectly regular series landed exactly on a threshold and passed under the
+// mutation it was meant to catch.
+
+type fakeLatest struct{ tests []RestoreTest }
+
+func (f *fakeLatest) RestoreTests(context.Context) []RestoreTest { return f.tests }
+
+type fakeProven struct{ tests []RestoreTest }
+
+func (f *fakeProven) ProvenRestoreTests(context.Context) []RestoreTest { return f.tests }
+
+func rt(tier, archive string, pass bool, at time.Time) RestoreTest {
+	return RestoreTest{
+		SourceArchive: archive, SourceTier: tier, Pass: pass,
+		Verified: "boot+running", TestedAt: at.UTC().Format(time.RFC3339),
+	}
+}
+
+// mergeCollector builds a Collector with only the two restore-test seams wired — the merge is what
+// is under test, not the rest of the collection.
+func mergeCollector(latest, proven []RestoreTest) *Collector {
+	c := &Collector{}
+	if latest != nil {
+		c.restoreTests = &fakeLatest{tests: latest}
+	}
+	if proven != nil {
+		c.provenTests = &fakeProven{tests: proven}
+	}
+	return c
+}
+
+func findTier(got []RestoreTest, tier string) (RestoreTest, int) {
+	var hit RestoreTest
+	n := 0
+	for _, e := range got {
+		if e.SourceTier == tier {
+			hit, n = e, n+1
+		}
+	}
+	return hit, n
+}
+
+// ── SCENARIO A — a proof survives a restart and reaches the hub ──────────────────────────────
+//
+// COMPANION RED-PROOF (observed 2026-08-03): delete the `c.provenTests` merge from
+// collectRestoreTests (return the in-memory slice as it used to) →
+//
+//	--- FAIL: TestMerge_ProofSurvivesARestart
+//	    restoretest_merge_test.go: after a restart the persisted proof must be reported; got 0 entr(ies)
+//
+// which is exactly the live observation: `0 restore-tests`. Restored.
+func TestMerge_ProofSurvivesARestart(t *testing.T) {
+	provenAt := time.Date(2026, 8, 3, 13, 25, 14, 0, time.UTC) // the real run's timestamp
+	// After a restart the in-memory store is EMPTY — this is the whole point.
+	c := mergeCollector([]RestoreTest{}, []RestoreTest{
+		rt("pbs", "felhom-pbs:backup/ct/9201/2026-07-28T04:49:43Z", true, provenAt),
+	})
+
+	got := c.collectRestoreTests(context.Background())
+	if len(got) != 1 {
+		t.Fatalf("after a restart the persisted proof must be reported; got %d entr(ies): %+v", len(got), got)
+	}
+	e := got[0]
+	if e.SourceArchive != "felhom-pbs:backup/ct/9201/2026-07-28T04:49:43Z" {
+		t.Fatalf("the entry must name the archive that was proven — the hub keys on it; got %q", e.SourceArchive)
+	}
+	if e.SourceTier != "pbs" || !e.Pass {
+		t.Fatalf("the entry must be a PASS on the tier it was proven on; got tier=%q pass=%v", e.SourceTier, e.Pass)
+	}
+	if e.TestedAt != provenAt.Format(time.RFC3339) {
+		t.Fatalf("the entry must carry the ORIGINAL test time, not now(); got %q", e.TestedAt)
+	}
+}
+
+// ── SCENARIO B — the report does not invent a pass ───────────────────────────────────────────
+//
+// COMPANION RED-PROOF (observed): make the state layer emit an entry for an unproven tier (drop the
+// `reportable()` filter in ProvenRestoreTests, so a legacy record with no archive is emitted) — the
+// equivalent at this layer is a proven-source that returns an entry for a tier nothing proved, which
+// this test injects directly and the assertion below rejects.
+func TestMerge_NeverInventsAPassForAnUnprovenTier(t *testing.T) {
+	// Nothing proven anywhere: no in-memory result, no persisted proof.
+	c := mergeCollector([]RestoreTest{}, []RestoreTest{})
+	if got := c.collectRestoreTests(context.Background()); len(got) != 0 {
+		t.Fatalf("a tier with no proof must produce NO entry — an unproven tier reading as proven is "+
+			"worse than the defect being fixed; got %+v", got)
+	}
+
+	// And an entry the state layer could not describe (no tier) is never promoted into a proof.
+	c2 := mergeCollector([]RestoreTest{}, []RestoreTest{
+		{SourceArchive: "local:backup/x.tar.zst", SourceTier: "", Pass: true,
+			TestedAt: time.Date(2026, 8, 1, 4, 41, 58, 0, time.UTC).Format(time.RFC3339)},
+	})
+	if got := c2.collectRestoreTests(context.Background()); len(got) != 0 {
+		t.Fatalf("a persisted record with no tier is not a usable proof and must be dropped; got %+v", got)
+	}
+}
+
+// ── SCENARIO C — a fresh in-memory result wins, and never duplicates ─────────────────────────
+//
+// COMPANION RED-PROOF (observed 2026-08-03): remove the de-duplication (append every persisted entry
+// unconditionally) →
+//
+//	--- FAIL: TestMerge_NewerWinsAndNeverDuplicatesATier
+//	    restoretest_merge_test.go: one entry per tier; got 2 for "pbs" — the hub would read two tests
+//
+// Restored.
+func TestMerge_NewerWinsAndNeverDuplicatesATier(t *testing.T) {
+	lastWeek := time.Date(2026, 7, 27, 19, 55, 41, 0, time.UTC) // jittered, from the real box
+	fiveMinAgo := time.Date(2026, 8, 3, 13, 25, 14, 0, time.UTC)
+
+	c := mergeCollector(
+		[]RestoreTest{rt("pbs", "felhom-pbs:backup/ct/9201/new", true, fiveMinAgo)},
+		[]RestoreTest{rt("pbs", "felhom-pbs:backup/ct/9201/old", true, lastWeek)},
+	)
+	got := c.collectRestoreTests(context.Background())
+	e, n := findTier(got, "pbs")
+	if n != 1 {
+		t.Fatalf("one entry per tier; got %d for \"pbs\" — the hub would read two tests: %+v", n, got)
+	}
+	if e.SourceArchive != "felhom-pbs:backup/ct/9201/new" {
+		t.Fatalf("the NEWER result must win; got %q tested %q", e.SourceArchive, e.TestedAt)
+	}
+
+	// ...and the older-in-memory / newer-persisted direction, which is the post-restart case.
+	c2 := mergeCollector(
+		[]RestoreTest{rt("pbs", "felhom-pbs:backup/ct/9201/old", true, lastWeek)},
+		[]RestoreTest{rt("pbs", "felhom-pbs:backup/ct/9201/new", true, fiveMinAgo)},
+	)
+	e2, n2 := findTier(c2.collectRestoreTests(context.Background()), "pbs")
+	if n2 != 1 || e2.SourceArchive != "felhom-pbs:backup/ct/9201/new" {
+		t.Fatalf("newest must win regardless of which source it came from; got %d entr(ies), archive %q", n2, e2.SourceArchive)
+	}
+}
+
+// ── SCENARIO D — a failure still reaches the hub ─────────────────────────────────────────────
+//
+// The merge must not mask a failure with an older stored success. A failing tier is retried at the
+// next evaluation and its record lives ONLY in memory, so losing it here would silence the loudest
+// DR signal this system produces.
+func TestMerge_AFailureIsStillReported(t *testing.T) {
+	provenLastWeek := time.Date(2026, 7, 27, 19, 55, 41, 0, time.UTC)
+	failedJustNow := time.Date(2026, 8, 3, 13, 41, 7, 0, time.UTC)
+
+	c := mergeCollector(
+		[]RestoreTest{rt("pbs", "felhom-pbs:backup/ct/9201/new", false, failedJustNow)},
+		[]RestoreTest{rt("pbs", "felhom-pbs:backup/ct/9201/old", true, provenLastWeek)},
+	)
+	e, n := findTier(c.collectRestoreTests(context.Background()), "pbs")
+	if n != 1 {
+		t.Fatalf("one entry per tier; got %d: %+v", n, c.collectRestoreTests(context.Background()))
+	}
+	if e.Pass {
+		t.Fatalf("a FAILURE newer than the stored proof must be what is reported — masking it would "+
+			"silence the loudest DR signal there is; got pass=%v archive=%q", e.Pass, e.SourceArchive)
+	}
+}
+
+// Two different tiers are both reported — the merge is per tier, not a single slot.
+func TestMerge_BothTiersSurvive(t *testing.T) {
+	c := mergeCollector(
+		[]RestoreTest{rt("local", "felhom-backup:backup/vzdump-lxc-9201-a.tar.zst", true,
+			time.Date(2026, 8, 3, 4, 44, 50, 0, time.UTC))},
+		[]RestoreTest{rt("pbs", "felhom-pbs:backup/ct/9201/x", true,
+			time.Date(2026, 8, 2, 5, 12, 33, 0, time.UTC))},
+	)
+	got := c.collectRestoreTests(context.Background())
+	if _, n := findTier(got, "local"); n != 1 {
+		t.Fatalf("the in-memory tier must survive the merge; got %+v", got)
+	}
+	if _, n := findTier(got, "pbs"); n != 1 {
+		t.Fatalf("the persisted tier must survive the merge; got %+v", got)
+	}
+}
+
+// A malformed timestamp must never displace a good entry — "unparseable" is not "newest".
+func TestMerge_MalformedTimestampNeverWins(t *testing.T) {
+	good := rt("pbs", "felhom-pbs:backup/ct/9201/good", true, time.Date(2026, 8, 3, 13, 25, 14, 0, time.UTC))
+	bad := RestoreTest{SourceArchive: "felhom-pbs:backup/ct/9201/bad", SourceTier: "pbs", Pass: true, TestedAt: "not-a-time"}
+
+	c := mergeCollector([]RestoreTest{good}, []RestoreTest{bad})
+	e, n := findTier(c.collectRestoreTests(context.Background()), "pbs")
+	if n != 1 || e.SourceArchive != "felhom-pbs:backup/ct/9201/good" {
+		t.Fatalf("an unparseable timestamp must not displace a good entry; got %d entr(ies), archive %q", n, e.SourceArchive)
+	}
+}
+
+// A nil proven-source leaves the pre-R-189 behaviour exactly as it was.
+func TestMerge_NilProvenSourceIsANoOp(t *testing.T) {
+	only := rt("local", "felhom-backup:backup/x.tar.zst", true, time.Date(2026, 8, 3, 4, 44, 50, 0, time.UTC))
+	c := mergeCollector([]RestoreTest{only}, nil)
+	got := c.collectRestoreTests(context.Background())
+	if len(got) != 1 || got[0].SourceArchive != only.SourceArchive {
+		t.Fatalf("a nil durable source must not change anything; got %+v", got)
+	}
+}