diff --git a/cmd/mesh-controller/chain.go b/cmd/mesh-controller/chain.go
index f54e6258..83239d20 100644
--- a/cmd/mesh-controller/chain.go
+++ b/cmd/mesh-controller/chain.go
@@ -7,6 +7,7 @@ import (
 	"time"
 
 	"github.com/novox/mesh-controller/internal/chain"
+	"github.com/novox/mesh-controller/internal/conditions"
 	"github.com/novox/mesh-controller/internal/inventory"
 	"github.com/novox/mesh-controller/internal/link"
 )
@@ -43,6 +44,8 @@ func attachTheChain(ctx context.Context, inv *inventory.Inventory, server *link.
 	inv.UseChain(c)
 	// And the requests the move of delivery 1 found never handed over, asked again once (askAgain), once it is serving.
 	go askAgainSoon(ctx, inv)
+	// And what delivery 1 recorded of what each machine was sent, copied onto the keys of the assignments (CopySentBuilds).
+	go copySentBuildsSoon(ctx, inv)
 	return nil
 }
 
@@ -87,3 +90,43 @@ func askAgainSoon(ctx context.Context, inv *inventory.Inventory) {
 		askAgain(ctx, inv)
 	}
 }
+
+// kindSentBuildsNotCopied is the condition of the one-time copy of node.sent_builds onto the assignments' keys that has not
+// succeeded: until it has, a module an assignment pulled in may be missing from what a machine is read to run.
+const kindSentBuildsNotCopied = "sent-builds-not-copied"
+
+// copySentBuildsSoon copies what the store recorded of what each machine was sent onto the keys of the assignments, as soon
+// as this controller holds the lease (the chain refuses a write before), and tries again every half minute while it fails,
+// each time it fails saying so as an urgent condition until it has worked. It is idempotent: CopySentBuilds overwrites no key
+// that names a commit and empties each column it has copied.
+func copySentBuildsSoon(ctx context.Context, inv *inventory.Inventory) {
+	failed := false
+	for {
+		_, err := inv.CopySentBuilds(ctx)
+		o := conditions.Observation{Scope: conditions.ScopeBuild, ID: kindSentBuildsNotCopied, Token: kindSentBuildsNotCopied,
+			Kind: kindSentBuildsNotCopied, Severity: conditions.Urgent, Resolver: conditions.ResolverOperator,
+			Source: "chain", Summary: "what each machine was sent is not copied onto its assignments: "}
+		if err != nil {
+			fmt.Printf("chain: what the machines were sent is not copied onto the assignments: %v\n", err)
+			if keeper := conditionsFrom; keeper != nil && !failed {
+				o.Summary += err.Error()
+				if _, oerr := keeper.Observe(ctx, o); oerr == nil {
+					failed = true
+				}
+			}
+		} else {
+			if keeper := conditionsFrom; keeper != nil && failed {
+				_, _ = keeper.Clear(ctx, o.Key(), "copied")
+			}
+			return
+		}
+		select {
+		case <-ctx.Done():
+			return
+		case <-time.After(chainMoveRetry):
+		}
+	}
+}
+
+// chainMoveRetry is how long the copy waits before it tries again.
+const chainMoveRetry = 30 * time.Second
diff --git a/cmd/mesh-controller/chain_no_table_integration_test.go b/cmd/mesh-controller/chain_no_table_integration_test.go
index 0bb3a10a..20181348 100644
--- a/cmd/mesh-controller/chain_no_table_integration_test.go
+++ b/cmd/mesh-controller/chain_no_table_integration_test.go
@@ -13,8 +13,7 @@ import (
 // **Acceptance 12 of design 47: no table in the controller's store holds builds, rollouts or assignments** (novox/hq ADR
 // 0408, issue 1111). A delivery is driven through the live trigger — a merge heard, its batch cut into a plan, the plan's
 // build asked and answered, the assignment made — until a build, a rollout and an assignment exist; they are read from the
-// chain, and then the store's own catalog is read: none of the tables of the chain is in it, nor the column that held what
-// a machine was sent, nor the function that raised the generation from the assignment table; the table that stays, stays.
+// chain, and then the store's own catalog is read: none of the tables of the chain is in it, nor the function that raised the generation from the assignment table; the table that stays, stays.
 func TestNoTableOfTheControllersStoreHoldsBuildsRolloutsOrAssignments(t *testing.T) {
 	open := windowed(t)
 	everyHeadWaits(t)
@@ -80,9 +79,6 @@ func TestNoTableOfTheControllersStoreHoldsBuildsRolloutsOrAssignments(t *testing
 			t.Errorf("the table %s, which stays, is gone", table)
 		}
 	}
-	if rows := inv.QueryForTest(t, `select count(*) from information_schema.columns where table_schema = 'public' and column_name = 'sent_builds'`); rows[0][0] != "0" {
-		t.Errorf("a column sent_builds is in the store: %v", rows)
-	}
 	if rows := inv.QueryForTest(t, `select count(*) from pg_proc where proname = 'raise_assignment_generation'`); rows[0][0] != "0" {
 		t.Errorf("the function raise_assignment_generation is in the store: %v", rows)
 	}
diff --git a/internal/inventory/chain_drop_test.go b/internal/inventory/chain_drop_test.go
index 80c20517..12a9b3ea 100644
--- a/internal/inventory/chain_drop_test.go
+++ b/internal/inventory/chain_drop_test.go
@@ -80,8 +80,8 @@ func TestMigration0105RefusesAStoreWhoseRowsWereNotMovedAndDropsTheTablesOfAMove
 			t.Errorf("the table %s is gone", stays)
 		}
 	}
-	if rows := inv.QueryForTest(t, `select count(*) from information_schema.columns where table_name = 'node' and column_name = 'sent_builds'`); rows[0][0] != "0" {
-		t.Errorf("node.sent_builds is still a column")
+	if rows := inv.QueryForTest(t, `select count(*) from information_schema.columns where table_name = 'node' and column_name = 'sent_builds'`); rows[0][0] != "1" {
+		t.Errorf("node.sent_builds, which stays as the source of the copy, is gone")
 	}
 	if rows := inv.QueryForTest(t, `select count(*) from pg_proc where proname = 'raise_assignment_generation'`); rows[0][0] != "0" {
 		t.Errorf("the function raise_assignment_generation is still in the store")
diff --git a/internal/inventory/chain_links.go b/internal/inventory/chain_links.go
index 69458990..56ec03b4 100644
--- a/internal/inventory/chain_links.go
+++ b/internal/inventory/chain_links.go
@@ -2,8 +2,11 @@ package inventory
 
 import (
 	"context"
+	"encoding/json"
 	"errors"
 	"fmt"
+	"maps"
+	"slices"
 	"sort"
 	"time"
 
@@ -254,3 +257,106 @@ func (i *Inventory) recordRun(ctx context.Context, c *chain.Chain, node, module,
 	}
 	return fmt.Errorf("the assignment kept moving under the write")
 }
+
+// CopySentBuilds copies what delivery 1 recorded in node.sent_builds onto the keys of the assignments, once, at the start of
+// the controller that holds the lease and has attached the chain (issue 1109, review round 1): delivery 1 wrote no commit onto
+// the key of a module an assignment pulled in, so without it those modules would be missing from SentBuilds although the
+// machine is known to have been sent. A key that names a commit is never overwritten, so it is idempotent; once a node's keys
+// are written its column is emptied, so a later restart cannot lay a stale commit over a key a later send cleared or ended.
+// It answers how many keys it wrote; an error is raised by the caller as a condition.
+func (i *Inventory) CopySentBuilds(ctx context.Context) (int, error) {
+	c, err := i.theChain(ctx)
+	if err != nil {
+		return 0, err
+	}
+	rows, err := i.store.Pool().Query(ctx, `select name, sent_builds from node where sent_builds is not null`)
+	if err != nil {
+		return 0, err
+	}
+	type kept struct {
+		name string
+		sent map[string]string
+	}
+	var all []kept
+	for rows.Next() {
+		var name string
+		var raw []byte
+		if err := rows.Scan(&name, &raw); err != nil {
+			rows.Close()
+			return 0, err
+		}
+		sent := map[string]string{}
+		if err := json.Unmarshal(raw, &sent); err != nil {
+			rows.Close()
+			return 0, fmt.Errorf("what %s was sent, in the store, cannot be read: %w", name, err)
+		}
+		all = append(all, kept{name, sent})
+	}
+	rows.Close()
+	if err := rows.Err(); err != nil {
+		return 0, err
+	}
+	now := time.Now().UTC()
+	for _, k := range all {
+		if err := i.copySentBuildsOf(ctx, c, k.name, k.sent, now); err != nil {
+			return 0, fmt.Errorf("what %s was sent cannot be copied onto its assignments: %w", k.name, err)
+		}
+		if _, err := i.store.Pool().Exec(ctx, `update node set sent_builds = null where name = $1`, k.name); err != nil {
+			return 0, err
+		}
+	}
+	return len(all), nil
+}
+
+// copySentBuildsOf is CopySentBuilds for one node, over a chain: for each module the node was sent, a standing key that
+// names no commit gets it (and the build, when one is known; no rollout), and where no key stands a standing pulled-in key is
+// made. A key with a commit, a hand send's unknown and a wait for a build are left as they are.
+func (i *Inventory) copySentBuildsOf(ctx context.Context, c *chain.Chain, node string, sent map[string]string, at time.Time) error {
+	for _, module := range slices.Sorted(maps.Keys(sent)) {
+		commit := sent[module]
+		if commit == "" {
+			continue
+		}
+		key := assignmentKey(node, module)
+		build, err := i.chainBuildOf(ctx, c, module, commit)
+		if err != nil {
+			return err
+		}
+		for try := 0; ; try++ {
+			if try == casTries {
+				return fmt.Errorf("the assignment %s kept moving under the write", key)
+			}
+			cur, found, err := c.Assignments.Get(ctx, key)
+			if err != nil {
+				return err
+			}
+			if found && (cur.Value.State != "" || cur.Value.Commit != "" || !cur.Value.SentUnknown.IsZero()) {
+				break
+			}
+			next := cur.Value
+			if !found || !cur.Value.Stands() {
+				next = chain.Assignment{Node: node, Module: module, PulledIn: true, Since: at}
+			}
+			next.Commit, next.Build = commit, build
+			if next.Since.IsZero() {
+				next.Since = at
+			}
+			if !found {
+				_, err = c.Assignments.Create(ctx, key, next)
+				if errors.Is(err, chain.ErrExists) {
+					continue
+				}
+			} else {
+				_, err = c.Assignments.Update(ctx, key, next, cur.Revision)
+				if errors.Is(err, chain.ErrMoved) {
+					continue
+				}
+			}
+			if err != nil {
+				return err
+			}
+			break
+		}
+	}
+	return nil
+}
diff --git a/internal/inventory/chain_sent_copy_test.go b/internal/inventory/chain_sent_copy_test.go
new file mode 100644
index 00000000..49bf9474
--- /dev/null
+++ b/internal/inventory/chain_sent_copy_test.go
@@ -0,0 +1,90 @@
+package inventory
+
+import (
+	"testing"
+	"time"
+
+	"github.com/novox/mesh-controller/internal/chain"
+)
+
+// **What delivery 1 recorded in node.sent_builds is copied onto the keys of the assignments, once** (issue 1109, review
+// round 1): a module pulled in by an assignment had no commit on its key, so it would fall out of SentBuilds. The copy
+// creates a standing pulled-in key where none stands, fills a standing key that names no commit (commit, and the build
+// when one is known, no rollout), and overwrites nothing: a key with a commit, a hand send's unknown, a wait for a build.
+func TestWhatTheColumnRecordedIsCopiedOntoTheKeysAndOverwritesNothing(t *testing.T) {
+	inv, c := anInventoryOnTheChain(t)
+	ctx := t.Context()
+	at := time.Date(2026, 10, 18, 4, 0, 0, 0, time.UTC)
+	if _, err := c.Builds.Create(ctx, "b-wg", chain.Build{ID: "b-wg", Module: "mesh-wireguard", Commit: "c-wg"}); err != nil {
+		t.Fatal(err)
+	}
+	put := func(module string, a chain.Assignment) {
+		a.Node, a.Module = "laptop", module
+		if _, err := c.Assignments.Create(ctx, assignmentKey("laptop", module), a); err != nil {
+			t.Fatal(err)
+		}
+	}
+	put("notes", chain.Assignment{Assigned: at})                                 // assigned, no commit yet
+	put("web", chain.Assignment{Assigned: at, Commit: "c-web-new", Build: "b1"}) // already has one
+	put("hand", chain.Assignment{Assigned: at, SentUnknown: at})                 // a hand send since
+	put("waits", chain.Assignment{Assigned: at, State: chain.StatePending})      // a wait for a build
+	put("ended", chain.Assignment{Assigned: at, Ended: at})                      // unassigned
+	sent := map[string]string{"notes": "c-notes", "web": "c-web-old", "mesh-wireguard": "c-wg", "hand": "c-hand",
+		"waits": "c-waits", "ended": "c-ended"}
+
+	for pass := 0; pass < 2; pass++ { // and the second pass changes nothing
+		if err := inv.copySentBuildsOf(ctx, c, "laptop", sent, at); err != nil {
+			t.Fatal(err)
+		}
+		get := func(module string) chain.Assignment {
+			t.Helper()
+			k, found, err := c.Assignments.Get(ctx, assignmentKey("laptop", module))
+			if err != nil || !found {
+				t.Fatalf("%s: %v %v", module, found, err)
+			}
+			return k.Value
+		}
+		if a := get("notes"); a.Commit != "c-notes" || a.Rollout != "" || !a.Stands() || a.PulledIn {
+			t.Errorf("notes: %+v", a)
+		}
+		if a := get("web"); a.Commit != "c-web-new" || a.Build != "b1" {
+			t.Errorf("a key with a commit was overwritten: %+v", a)
+		}
+		if a := get("hand"); a.Commit != "" || a.SentUnknown.IsZero() {
+			t.Errorf("a hand send's unknown was overwritten: %+v", a)
+		}
+		if a := get("waits"); a.Commit != "" || a.State != chain.StatePending {
+			t.Errorf("a wait was overwritten: %+v", a)
+		}
+		if a := get("mesh-wireguard"); a.Commit != "c-wg" || a.Build != "b-wg" || !a.PulledIn || !a.Stands() || a.Rollout != "" {
+			t.Errorf("the pulled-in module has no standing key of its own: %+v", a)
+		}
+		if a := get("ended"); a.Commit != "c-ended" || !a.Stands() || !a.PulledIn {
+			t.Errorf("an ended key is not made to stand again as pulled in: %+v", a)
+		}
+	}
+}
+
+// The copy reads the column of the store, writes the keys, and empties the column it has copied: SentBuilds then answers the
+// pulled-in module, and a second copy finds nothing to do.
+func TestTheColumnOfASentMachineIsCopiedOntoItsKeysAndEmptied(t *testing.T) {
+	inv := ForTest(t)
+	ctx := t.Context()
+	if _, err := inv.AddNode(ctx, "laptop"); err != nil {
+		t.Fatal(err)
+	}
+	inv.ExecForTest(t, `update node set sent_builds = '{"mesh-wireguard": "c-wg"}'::jsonb, sent_at = now() where name = 'laptop'`)
+	if n, err := inv.CopySentBuilds(ctx); err != nil || n != 1 {
+		t.Fatalf("the copy did %d nodes (%v)", n, err)
+	}
+	got, known, err := inv.SentBuilds(ctx, "laptop")
+	if err != nil || !known || got["mesh-wireguard"] != "c-wg" {
+		t.Fatalf("SentBuilds answers %v, known %v (%v)", got, known, err)
+	}
+	if rows := inv.QueryForTest(t, `select count(*) from node where sent_builds is not null`); rows[0][0] != "0" {
+		t.Fatalf("the column was not emptied: %v", rows)
+	}
+	if n, err := inv.CopySentBuilds(ctx); err != nil || n != 0 {
+		t.Fatalf("a second copy did %d nodes (%v)", n, err)
+	}
+}
diff --git a/internal/inventory/chain_source_test.go b/internal/inventory/chain_source_test.go
index 99f4c76c..d5f5cac2 100644
--- a/internal/inventory/chain_source_test.go
+++ b/internal/inventory/chain_source_test.go
@@ -21,10 +21,10 @@ var sqlStatement = regexp.MustCompile(`(?is)^\s*(select|insert|update|delete|alt
 
 // **No code names a table of the chain** (acceptance 12, issue 1096), found by reading the sources: a string literal of any
 // non-test file of internal/ or cmd/ that names one after from, into, update, join, delete from, references or table —
-// build_gate and port_assignment are other words — or the column sent_builds. This is the static half of the proof; the
+// build_gate and port_assignment are other words —. This is the static half of the proof; the
 // integration test reads the catalog.
 func TestNoCodeNamesATableOfTheChain(t *testing.T) {
-	names := regexp.MustCompile(`(?i)\b(from|into|update|join|delete\s+from|references|table)\s+(` + strings.Join(chainTables, "|") + `)\b|\bsent_builds\b`)
+	names := regexp.MustCompile(`(?i)\b(from|into|update|join|delete\s+from|references|table)\s+(` + strings.Join(chainTables, "|") + `)\b`)
 	var found []string
 	for _, root := range []string{"../../internal", "../../cmd"} {
 		err := filepath.WalkDir(root, func(path string, d fs.DirEntry, err error) error {
@@ -71,11 +71,10 @@ func TestNoCodeNamesATableOfTheChain(t *testing.T) {
 
 // The scan sees what it says it sees: planted, a string naming a table is found, and a comment or a word beside is not.
 func TestTheSourceScanFindsATablePlanted(t *testing.T) {
-	names := regexp.MustCompile(`(?i)\b(from|into|update|join|delete\s+from|references|table)\s+(` + strings.Join(chainTables, "|") + `)\b|\bsent_builds\b`)
+	names := regexp.MustCompile(`(?i)\b(from|into|update|join|delete\s+from|references|table)\s+(` + strings.Join(chainTables, "|") + `)\b`)
 	for text, want := range map[string]bool{
 		"select id from build where id = $1":         true,
 		"insert into assignment (node, module)":      true,
-		"update node set sent_builds = $1":           true,
 		"select 1 from build_gate":                   false,
 		"delete from port_assignment":                false,
 		"select a from build_request a join build b": true,
@@ -116,11 +115,14 @@ func TestTheLastMigrationDropsTheTablesOfTheChain(t *testing.T) {
 			t.Errorf("migration %d does not drop %s", last.Number, table)
 		}
 	}
-	for _, want := range []string{"drop function raise_assignment_generation()", "alter table node drop column sent_builds"} {
+	for _, want := range []string{"drop function raise_assignment_generation()"} {
 		if !strings.Contains(sql, want) {
 			t.Errorf("migration %d lacks %q", last.Number, want)
 		}
 	}
+	if strings.Contains(sql, "sent_builds") {
+		t.Errorf("migration %d touches node.sent_builds, which stays as the source of the copy (issue 1112 drops it)", last.Number)
+	}
 	if strings.Contains(sql, "build_gate") || strings.Contains(sql, "assignment_generation;") {
 		t.Errorf("migration %d touches a table that stays", last.Number)
 	}
diff --git a/internal/inventory/migrations/0105-the-chain-leaves-the-store.sql b/internal/inventory/migrations/0105-the-chain-leaves-the-store.sql
index 61c129f8..411c11b3 100644
--- a/internal/inventory/migrations/0105-the-chain-leaves-the-store.sql
+++ b/internal/inventory/migrations/0105-the-chain-leaves-the-store.sql
@@ -47,6 +47,6 @@ drop table pending_assignment;
 -- Its triggers go with it; the function they called goes here. The counter table stays: the controller raises it.
 drop table assignment;
 drop function raise_assignment_generation();
-alter table node drop column sent_builds;
--- No reader of it remains. build_gate stays (issue 1097).
+-- node.sent_builds STAYS, only as the source of the one-time copy onto the assignments' keys (issue 1109); dropping it is
+-- issue 1112. build_gate stays (issue 1097).
 drop table chain_moved;
diff --git a/testdata/store-tests b/testdata/store-tests
index 71222538..03d58c9b 100644
--- a/testdata/store-tests
+++ b/testdata/store-tests
@@ -156,3 +156,7 @@
 ./internal/inventory TestSentBuildsAnswersFromTheAssignmentsKeysOfTheNode
 ./internal/inventory TestASendReplacesTheWholeMapOfTheNodeAndAHandSendMakesItUnknown
 ./internal/inventory TestAFailedWriteOfTheLinksFailsTheRecordOfTheSend
+./internal/inventory TestMigration0105RefusesAStoreWhoseRowsWereNotMovedAndDropsTheTablesOfAMovedOne
+./internal/inventory TestMigration0105PassesAStoreThatNeverHeldARow
+./cmd/mesh-controller TestNoTableOfTheControllersStoreHoldsBuildsRolloutsOrAssignments
+./internal/inventory TestTheColumnOfASentMachineIsCopiedOntoItsKeysAndEmptied