Merge pull request 'A take is a comparison: the host's facts, former targets, and strays (hq ADR 0163)' (#63) from feat/a-take-is-a-comparison-the-hosts-facts into main

Every held thing carries what a take compares: for a found container its image and the image's date,
the networks it is on and the other containers on each, its mounts and published ports, beside the
declared image (and its date once pulled), ports and volumes, with the downgrade decided when both
dates are known; for a found file whether the declared content differs and how, as lines lost and
lines new. A resource whose target moved keeps the former target on record as an orphan, so the next
apply removes the container or file the host wrote under the old name (issue 097). Every apply reports
the strays: containers the mesh neither wrote nor holds.

cmd/mesh-host/main.go

@@ -818,10 +818,7 @@ func enrol(ctx context.Context, opts options) error {
 	// control plane cannot decide what a node should run without it, so it travels with the
 	// request instead of being asked for in a second round trip.
 	detected := profile.Detect(ctx, profile.Default(nil), opts.timeout)
-	reported := map[string]any{}
-	if raw, err := json.Marshal(detected); err == nil {
-		_ = json.Unmarshal(raw, &reported)
-	}
+	reported := profileAsReported(detected)
 
 	// Signed with the identity just generated, so the mesh can tell this machine from anyone else
 	// who knows its public key (novox/hq issue 083).
@@ -853,6 +850,13 @@ func enrol(ctx context.Context, opts options) error {
 		Fingerprint: firstNonEmpty(reply.Fingerprint, token.Fingerprint),
 		Signer:      firstNonEmpty2(reply.Signer, token.Signer),
 		Password:    reply.Password,
+		// **Which bus this membership is for, said rather than left empty** (novox/hq
+		// 04-ISSUES/146). The link refuses a membership that names another bus, and an empty name
+		// is not this one's — so a node enrolled without it came up and reconnected for ever
+		// against its own record: "this membership is for \"\", and the mesh's bus is nats". The
+		// reply does not carry it because there is one bus and the host knows which (ADR 0131);
+		// what was missing was writing that down where the link reads it.
+		Transport: link.OnNATS,
 	}
 	if mine.Membership.Password == "" {
 		// The mesh did not replace the token's secret, so it is still this node's broker
@@ -1411,7 +1415,8 @@ func applyAndKeep(ctx context.Context, opts options, raw []byte, signed *store.D
 		sched.Sync(declared, held)
 	}
 
-	report := link.Report{Carried: carriedPorts(updated), Declared: digestOf(raw), Host: runningVersion()}
+	report := link.Report{Carried: carriedPorts(updated), Declared: digestOf(raw), Host: runningVersion(),
+		Profile: profileAsReported(profile.Detect(ctx, profile.Default(nil), opts.timeout))}
 	// Which of this machine's links face outside, for the filter the mesh writes around them
 	// (novox/hq ADR 0140). Reported whatever the node's mode: a converged node's filter needs it,
 	// and an adopted one becomes converged without a further round trip. A machine that cannot read
@@ -1425,7 +1430,15 @@ func applyAndKeep(ctx context.Context, opts options, raw []byte, signed *store.D
 	// node never reads as converged (novox/hq ADR 0100).
 	for _, h := range updated.Held {
 		report.Held = append(report.Held, link.Held{ID: h.ID, Module: h.Module, Kind: h.Kind,
-			Target: h.Target, Since: h.Since, Changed: h.Changed, Kept: h.Kept})
+			Target: h.Target, Since: h.Since, Changed: h.Changed, Kept: h.Kept, Facts: factsAsReported(h.Facts)})
+	}
+	// And what runs here that nobody asked for (novox/hq ADR 0163).
+	if strays, err := apply.Strays(ctx, apply.ExecRunner, updated); err != nil {
+		fmt.Fprintf(os.Stderr, "mesh-host: applied, and could not list what else runs here: %v\n", err)
+	} else {
+		for _, s := range strays {
+			report.Strays = append(report.Strays, link.Stray{Kind: s.Kind, Name: s.Name, Detail: s.Detail})
+		}
 	}
 	if declared.Adoption != nil {
 		if updated.Firewall != nil {
@@ -1623,3 +1636,25 @@ func refuseOlder(kept store.Declared, keptErr error, sequence int64) error {
 	}
 	return nil
 }
+
+// profileAsReported is the profile as the mesh reads it — the same bytes enrolment sends, so a
+// report's profile and an enrolment's are one shape on the controller's side (novox/hq ADR 0161).
+func profileAsReported(detected profile.Profile) map[string]any {
+	reported := map[string]any{}
+	if raw, err := json.Marshal(detected); err == nil {
+		_ = json.Unmarshal(raw, &reported)
+	}
+	return reported
+}
+
+// factsAsReported is a held thing's facts as the mesh reads them: the same bytes the host keeps.
+func factsAsReported(f *store.Facts) map[string]any {
+	if f == nil {
+		return nil
+	}
+	out := map[string]any{}
+	if raw, err := json.Marshal(f); err == nil {
+		_ = json.Unmarshal(raw, &out)
+	}
+	return out
+}

examples/foundation-first-node-nats.lock

@@ -161,7 +161,7 @@
       "type": "file",
       "path": "/var/lib/mesh-bus-conf/accounts.conf",
       "mode": "0600",
-      "content": "// The first user list, carried by the installer because at genesis there is no mesh to\n// compose one. A bootstrap credential, rotated with the store's and replaced by the\n// controller's own composition from its first start onward.\naccounts {\n  MESH {\n    jetstream: enabled\n    users = [\n      { user: \"controller\", password: \"$2a$10$AHqJgOifIVbU41KmATiMhuXFs8xa7Wl2HuN4UVBCXdN2jIQzjqApy\", permissions: {\n        publish: { allow: [\"$JS.API.>\", \"$JS.ACK.CONTROL.controller.>\", \"$JS.ACK.EVENTS.controller.>\", \"_INBOX.enrol.>\", \"mesh.control.>\", \"mesh.mod.*.tool.>\", \"mesh.node.>\", \"mesh.seat.mesh-build-machine.accept.>\", \"mesh.seat.mesh-controller.event.applied\", \"mesh.seat.mesh-controller.event.built-before\", \"mesh.seat.mesh-controller.event.refused\"] }\n        subscribe: { allow: [\"$JS.API.>\", \"_DELIVER.controller\", \"_DELIVER.controller.>\", \"_INBOX.controller.>\", \"mesh.control.>\", \"mesh.mod.mesh-catalog.event.catching-up\", \"mesh.mod.mesh-catalog.event.upgraded\", \"mesh.mod.gitea.event.pull.merged\", \"mesh.seat.mesh-build-machine.event.built\"] }\n        allow_responses: { max: 1, ttl: \"1m\" }\n      } }\n    ]\n  }\n}\n"
+      "content": "// The first user list, carried by the installer because at genesis there is no mesh to\n// compose one. A bootstrap credential, rotated with the store's and replaced by the\n// controller's own composition from its first start onward.\naccounts {\n  MESH {\n    jetstream: enabled\n    users = [\n      { user: \"controller\", password: \"$2a$10$AHqJgOifIVbU41KmATiMhuXFs8xa7Wl2HuN4UVBCXdN2jIQzjqApy\", permissions: {\n        publish: { allow: [\"$JS.ACK.CONTROL.controller.>\", \"$JS.ACK.EVENTS.controller.>\", \"$JS.API.>\", \"_INBOX.enrol.>\", \"mesh.assignment.>\", \"mesh.control.>\", \"mesh.mod.*.tool.>\", \"mesh.node.>\", \"mesh.seat.mesh-build-machine.accept.>\", \"mesh.seat.mesh-controller.event.applied\", \"mesh.seat.mesh-controller.event.built-before\", \"mesh.seat.mesh-controller.event.refused\"] }\n        subscribe: { allow: [\"$JS.API.>\", \"_DELIVER.controller\", \"_DELIVER.controller.>\", \"_INBOX.controller.>\", \"mesh.control.>\", \"mesh.mod.gitea.event.pull.merged\", \"mesh.mod.mesh-catalog.event.catching-up\", \"mesh.mod.mesh-catalog.event.upgraded\", \"mesh.seat.mesh-build-machine.event.built\", \"mesh.seat.mesh-controller.tool.>\"] }\n        allow_responses: { max: 1, ttl: \"1m\" }\n      } }\n    ]\n  }\n}\n"
     },
     {
       "id": "broker",

internal/apply/facts_test.go

@@ -0,0 +1,97 @@
+package apply
+
+import (
+	"context"
+	"os"
+	"path/filepath"
+	"strings"
+	"testing"
+
+	"github.com/novox/mesh-host/internal/store"
+)
+
+// A take is a comparison (novox/hq ADR 0163): while a module's container is held, the host reports
+// the found image and its age beside the declared one, the networks and who else is on them, the
+// mounts and the ports — and says when the declared image is the older.
+func TestAHeldContainerCarriesTheFactsATakeCompares(t *testing.T) {
+	dir, page, m := predecessor(t)
+	m.containers["hello-web"].image = "web:1.27"
+	m.containers["hello-web"].imageID = "sha256:found"
+	m.containers["hello-web"].networks = []string{"predecessor_default"}
+	m.containers["hello-web"].mounts = []string{"/srv/web:/data"}
+	m.containers["hello-web"].ports = []string{"80/tcp>0.0.0.0:8080"}
+	m.images = map[string]string{"sha256:found": "2026-09-17T10:00:00Z", pinned: "2026-08-20T10:00:00Z"}
+	m.members = map[string][]string{"predecessor_default": {"hello-web", "office", "db"}}
+
+	_, state := applyAdopted(t, adopted(t, untakenWeb, webResources(page)), store.State{}, m, dir)
+	h, ok := state.HeldAt("hello-web.server")
+	if !ok || h.Facts == nil {
+		t.Fatalf("a held container carries no facts: %+v", h)
+	}
+	f := h.Facts
+	if f.Image != "web:1.27" || f.ImageCreated != "2026-09-17T10:00:00Z" {
+		t.Errorf("the found image and its age: %+v", f)
+	}
+	if f.DeclaredImage != pinned || f.DeclaredImageCreated != "2026-08-20T10:00:00Z" || !f.Downgrade {
+		t.Errorf("the declared image, its age, and that it is a downgrade: %+v", f)
+	}
+	if got := f.Networks["predecessor_default"]; len(got) != 2 || got[0] != "db" || got[1] != "office" {
+		t.Errorf("the neighbours on the found network, without the container itself: %v", f.Networks)
+	}
+	if len(f.Mounts) != 1 || f.Mounts[0] != "/srv/web:/data" || len(f.Ports) != 1 || f.Ports[0] != "80/tcp>0.0.0.0:8080" {
+		t.Errorf("mounts and ports as found: %+v", f)
+	}
+	// And the held file carries how the declared content differs from what was found.
+	p, ok := state.HeldAt("hello-web.page")
+	if !ok || p.Facts == nil || !p.Facts.Differs {
+		t.Fatalf("a held file that differs from the declared content does not say so: %+v", p)
+	}
+	joined := strings.Join(p.Facts.Difference, "\n")
+	if !strings.Contains(joined, "- the predecessor's page") || !strings.Contains(joined, "+ the mesh's page") {
+		t.Errorf("the difference does not show what is lost and what is new: %q", joined)
+	}
+	_ = os.Remove(filepath.Join(dir, "unused"))
+}
+
+// A declared image not yet on the machine leaves its age unknown and the comparison undecided.
+func TestAnImageNotYetPulledLeavesTheDowngradeUndecided(t *testing.T) {
+	dir, page, m := predecessor(t)
+	m.containers["hello-web"].image = "web:1.27"
+	m.containers["hello-web"].imageID = "sha256:found"
+	m.images = map[string]string{"sha256:found": "2026-09-17T10:00:00Z"}
+	_, state := applyAdopted(t, adopted(t, untakenWeb, webResources(page)), store.State{}, m, dir)
+	h, _ := state.HeldAt("hello-web.server")
+	if h.Facts == nil || h.Facts.DeclaredImageCreated != "" || h.Facts.Downgrade {
+		t.Fatalf("an unknown declared age decided a downgrade: %+v", h.Facts)
+	}
+}
+
+func TestTheDifferenceIsWhatIsLostAndWhatIsNew(t *testing.T) {
+	differs, lines := differenceOf("a\nprivate scope: local\nb\n", "a\nb\nupstream: public\n")
+	if !differs || len(lines) != 2 || lines[0] != "- private scope: local" || lines[1] != "+ upstream: public" {
+		t.Fatalf("got %v %v", differs, lines)
+	}
+	if differs, lines := differenceOf("same\n", "same\n"); differs || lines != nil {
+		t.Fatalf("identical content differs: %v %v", differs, lines)
+	}
+}
+
+// What runs on the machine that the mesh neither wrote nor holds is reported (ADR 0163).
+func TestStraysAreWhatRunsHereThatNobodyAsked(t *testing.T) {
+	m := &machine{containers: map[string]*fakeContainer{
+		"hello-web":  {id: "ours", running: true, image: "web:1"},
+		"gitea-old":  {id: "left-behind", running: true, image: "gitea:1.22"},
+		"held-thing": {id: "found", running: true, image: "x:1"},
+	}}
+	known := store.State{
+		Resources: []store.Applied{{ID: "hello-web.server", Type: "container", Target: "hello-web"}},
+		Held:      []store.Held{{ID: "other.server", Kind: "container", Target: "held-thing"}},
+	}
+	strays, err := Strays(context.Background(), m.run, known)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if len(strays) != 1 || strays[0].Name != "gitea-old" || !strings.Contains(strays[0].Detail, "gitea:1.22") {
+		t.Fatalf("strays: %+v", strays)
+	}
+}

internal/apply/hold.go

@@ -8,6 +8,7 @@ import (
 	"fmt"
 	"os"
 	"path/filepath"
+	"sort"
 	"strings"
 	"syscall"
 	"time"
@@ -433,6 +434,32 @@ type foundContainer struct {
 	id      string
 	running bool
 	spec    string
+	// What a take compares (novox/hq ADR 0163): the image and its id, the networks the container
+	// is on, its mounts and its published ports — empty from a runtime (or a test's fake) that
+	// answers the short form.
+	image    string
+	imageID  string
+	networks []string
+	mounts   []string
+	ports    []string
+}
+
+// foundFormat is what inspectFound asks the runtime for, tab-separated: the three a hold has
+// always needed, then the facts a take compares.
+const foundFormat = "{{.Id}}\t{{.State.Running}}\t{{index .Config.Labels \"" + specLabel + "\"}}" +
+	"\t{{.Config.Image}}\t{{.Image}}" +
+	"\t{{range $k, $v := .NetworkSettings.Networks}}{{$k}},{{end}}" +
+	"\t{{range .Mounts}}{{.Source}}:{{.Destination}},{{end}}" +
+	"\t{{range $p, $b := .NetworkSettings.Ports}}{{$p}}{{range $b}}>{{.HostIp}}:{{.HostPort}}{{end}},{{end}}"
+
+func splitList(s string) []string {
+	var out []string
+	for _, part := range strings.Split(s, ",") {
+		if part = strings.TrimSpace(part); part != "" {
+			out = append(out, part)
+		}
+	}
+	return out
 }
 
 // inspectFound reads a container by name the way a hold needs it: its id, whether it runs, and
@@ -451,8 +478,7 @@ func inspectFound(ctx context.Context, name string, run Runner) (foundContainer,
 	if err != nil {
 		return foundContainer{}, false, fmt.Errorf("%w, so nothing can be said about %q", err, name)
 	}
-	out, err := run(ctx, cri, "container", "inspect", "--format",
-		"{{.Id}}\t{{.State.Running}}\t{{index .Config.Labels \""+specLabel+"\"}}", name)
+	out, err := run(ctx, cri, "container", "inspect", "--format", foundFormat, name)
 	if err != nil {
 		if absent(err) {
 			return foundContainer{}, false, nil
@@ -466,14 +492,100 @@ func inspectFound(ctx context.Context, name string, run Runner) (foundContainer,
 			name, err)
 	}
 	parts := strings.Split(strings.TrimSpace(out), "\t")
-	for len(parts) < 3 {
+	for len(parts) < 8 {
 		parts = append(parts, "")
 	}
 	spec := strings.TrimSpace(parts[2])
 	if spec == "<no value>" {
 		spec = ""
 	}
-	return foundContainer{id: strings.TrimSpace(parts[0]), running: parts[1] == "true", spec: spec}, true, nil
+	return foundContainer{id: strings.TrimSpace(parts[0]), running: parts[1] == "true", spec: spec,
+		image: strings.TrimSpace(parts[3]), imageID: strings.TrimSpace(parts[4]),
+		networks: splitList(parts[5]), mounts: splitList(parts[6]), ports: splitList(parts[7])}, true, nil
+}
+
+// factsOf is what a take would compare for a found container (novox/hq ADR 0163): the found
+// image and when it was made, the networks and who else is on them, mounts and ports — beside
+// what the module declares, and the declared image's date when that image is on the machine.
+// Every question the runtime cannot answer leaves its fact empty; a preview says so rather than
+// guesses.
+func factsOf(ctx context.Context, seen foundContainer, res *declaration.Container, run Runner) *Facts {
+	cri, err := containerRuntime(ctx, run)
+	if err != nil {
+		return nil
+	}
+	f := &store.Facts{Image: seen.image, Mounts: seen.mounts, Ports: seen.ports,
+		DeclaredImage: res.Image, DeclaredPorts: res.Ports, DeclaredVolumes: res.Volumes}
+	if seen.imageID != "" {
+		if out, err := run(ctx, cri, "image", "inspect", "--format", "{{.Created}}", seen.imageID); err == nil {
+			f.ImageCreated = strings.TrimSpace(out)
+		}
+	}
+	if res.Image != "" {
+		if out, err := run(ctx, cri, "image", "inspect", "--format", "{{.Created}}", res.Image); err == nil {
+			f.DeclaredImageCreated = strings.TrimSpace(out)
+		}
+	}
+	if found, err := time.Parse(time.RFC3339Nano, f.ImageCreated); err == nil {
+		if declared, err := time.Parse(time.RFC3339Nano, f.DeclaredImageCreated); err == nil {
+			f.Downgrade = declared.Before(found)
+		}
+	}
+	for _, network := range seen.networks {
+		if f.Networks == nil {
+			f.Networks = map[string][]string{}
+		}
+		var members []string
+		if out, err := run(ctx, cri, "network", "inspect", "--format",
+			"{{range .Containers}}{{.Name}},{{end}}", network); err == nil {
+			for _, m := range splitList(out) {
+				if m != res.Name {
+					members = append(members, m)
+				}
+			}
+		}
+		sort.Strings(members)
+		f.Networks[network] = members
+	}
+	return (*Facts)(f)
+}
+
+// Facts is store.Facts, named here so hold's callers read as one vocabulary.
+type Facts = store.Facts
+
+// differenceOf is how a found file differs from the declared content: the lines only the found
+// file has, marked -, then the lines only the declared content has, marked +, in their own order,
+// bounded so a report stays a report. Not a diff tool's output: the question a take answers is
+// "what would be lost and what would be new", and that is these two lists.
+func differenceOf(found, declared string) (bool, []string) {
+	if found == declared {
+		return false, nil
+	}
+	const bound = 40
+	count := func(s string) map[string]int {
+		out := map[string]int{}
+		for _, line := range strings.Split(s, "\n") {
+			out[line]++
+		}
+		return out
+	}
+	inFound, inDeclared := count(found), count(declared)
+	var out []string
+	add := func(mark, s string, other map[string]int) {
+		seen := map[string]int{}
+		for _, line := range strings.Split(s, "\n") {
+			seen[line]++
+			if seen[line] > other[line] && len(out) < bound {
+				out = append(out, mark+" "+line)
+			}
+		}
+	}
+	add("-", found, inDeclared)
+	add("+", declared, inFound)
+	if len(out) >= bound {
+		out = append(out, "… and more")
+	}
+	return true, out
 }
 
 // absent is whether a runtime said the thing is not there, rather than failing to answer. Its own
@@ -540,6 +652,12 @@ func hold(ctx context.Context, sys system.System, r declaration.Resource, module
 			} else if digestOf(string(content)) != h.Digest {
 				changed = "rewritten"
 			}
+			// What a take would replace it with, and how that differs (novox/hq ADR 0163): a
+			// file declared whole is compared whole; one written into is not replaced at all.
+			if res.Into == "" {
+				differs, lines := differenceOf(string(content), res.Content)
+				h.Facts = &Facts{Differs: differs, Difference: lines}
+			}
 		}
 	case *declaration.Directory:
 		info, err := os.Lstat(res.Path)
@@ -628,6 +746,9 @@ func hold(ctx context.Context, sys system.System, r declaration.Resource, module
 		case h.Running && !seen.running:
 			changed = "stopped"
 		}
+		if exists {
+			h.Facts = factsOf(ctx, seen, res, run)
+		}
 	default:
 		return out, h, fmt.Errorf("a %s cannot be held", r.Kind())
 	}

internal/apply/hold_test.go

@@ -5,6 +5,7 @@ import (
 	"errors"
 	"os"
 	"path/filepath"
+	"sort"
 	"strings"
 	"testing"
 
@@ -18,6 +19,10 @@ import (
 // label when a host made it. Every command it is asked is written down.
 type machine struct {
 	containers map[string]*fakeContainer
+	// images is what `image inspect --format {{.Created}}` answers per image or id; members is
+	// what `network inspect` lists per network (ADR 0163).
+	images  map[string]string
+	members map[string][]string
 	asked   []string
 	// wgUp is what `wg show interfaces` answers: the tunnels up on the machine.
 	wgUp string
@@ -97,6 +102,9 @@ type fakeContainer struct {
 	id      string
 	running bool
 	spec    string
+	// What a take compares (ADR 0163), answered in the long inspect form when set.
+	image, imageID          string
+	networks, mounts, ports []string
 }
 
 func (m *machine) run(_ context.Context, name string, args ...string) (string, error) {
@@ -140,9 +148,38 @@ func (m *machine) run(_ context.Context, name string, args ...string) (string, e
 			running = "true"
 		}
 		if strings.HasPrefix(args[3], "{{.Id}}") {
-			return c.id + "\t" + running + "\t" + c.spec + "\n", nil
+			line := c.id + "\t" + running + "\t" + c.spec
+			if c.image != "" {
+				line += "\t" + c.image + "\t" + c.imageID + "\t" + strings.Join(c.networks, ",") + "," +
+					"\t" + strings.Join(c.mounts, ",") + "," + "\t" + strings.Join(c.ports, ",") + ","
+			}
+			return line + "\n", nil
 		}
 		return running + "\t" + c.spec + "\n", nil
+	case "image":
+		if len(args) > 1 && args[1] == "inspect" {
+			if created, ok := m.images[args[len(args)-1]]; ok {
+				return created + "\n", nil
+			}
+			return "", errors.New("no such image")
+		}
+		return "", nil
+	case "network":
+		if len(args) > 1 && args[1] == "inspect" {
+			return strings.Join(m.members[args[len(args)-1]], ",") + ",\n", nil
+		}
+		return "", nil
+	case "ps":
+		var lines []string
+		for name, c := range m.containers {
+			state := "exited"
+			if c.running {
+				state = "running"
+			}
+			lines = append(lines, name+"\t"+c.image+"\t"+state)
+		}
+		sort.Strings(lines)
+		return strings.Join(lines, "\n") + "\n", nil
 	case "rm":
 		delete(m.containers, args[len(args)-1])
 		return "", nil

internal/apply/strays.go

@@ -0,0 +1,54 @@
+package apply
+
+import (
+	"context"
+	"sort"
+	"strings"
+
+	"github.com/novox/mesh-host/internal/declaration"
+	"github.com/novox/mesh-host/internal/store"
+)
+
+// Strays is what runs on the machine that the mesh neither wrote nor holds (novox/hq ADR 0163):
+// every container the runtime has that no record names and no hold names. The question nothing
+// answered on 2026-09-23, when a renamed resource left its old container running for a day; asked
+// on every apply now, and reported, so a thing left behind is seen the day it is left.
+//
+// Containers only, today. A listener nobody declared is harder to attribute to a thing, and the
+// machine's own services are not strays; that account is issue 160's.
+func Strays(ctx context.Context, run Runner, known store.State) ([]store.Stray, error) {
+	cri, err := containerRuntime(ctx, run)
+	if err != nil {
+		return nil, nil // a machine with no runtime has no containers to stray
+	}
+	out, err := run(ctx, cri, "ps", "-a", "--format", "{{.Names}}\t{{.Image}}\t{{.State}}")
+	if err != nil {
+		return nil, err
+	}
+	ours := map[string]bool{}
+	for _, r := range known.Resources {
+		if declaration.Type(r.Type) == declaration.TypeContainer {
+			ours[r.Target] = true
+		}
+	}
+	for _, h := range known.Held {
+		if h.Kind == string(declaration.TypeContainer) {
+			ours[h.Target] = true
+		}
+	}
+	var strays []store.Stray
+	for _, line := range strings.Split(strings.TrimSpace(out), "\n") {
+		parts := strings.Split(line, "\t")
+		name := strings.TrimSpace(parts[0])
+		if name == "" || ours[name] {
+			continue
+		}
+		detail := ""
+		if len(parts) > 2 {
+			detail = strings.TrimSpace(parts[1]) + ", " + strings.TrimSpace(parts[2])
+		}
+		strays = append(strays, store.Stray{Kind: string(declaration.TypeContainer), Name: name, Detail: detail})
+	}
+	sort.Slice(strays, func(i, j int) bool { return strays[i].Name < strays[j].Name })
+	return strays, nil
+}

internal/link/asking_nats.go

@@ -3,6 +3,7 @@ package link
 import (
 	"context"
 	"crypto/rand"
+	"crypto/sha256"
 	"encoding/hex"
 	"errors"
 	"fmt"
@@ -63,8 +64,15 @@ func presentNats(_ context.Context, to Approach, node, secret string,
 	// subscribe its own inbox and nothing else (design 25 §6). The secret is its password, the same
 	// string the request claims, so the server proves somebody holds the token and the request
 	// proves the same thing to the controller without it having to ask the server who connected.
+	// **Its own inbox space, because that is the only one it may listen in** (novox/hq
+	// 04-ISSUES/146). A JetStream publish waits for the stream's acknowledgement on an inbox the
+	// client picks, and the client's default is `_INBOX.<random>` — which this user may not
+	// subscribe to, so the enrolment failed with a permissions violation on a subject nobody had
+	// chosen. The permission is `_INBOX.enrol.<node>.>` (design 25 §6), so the client is told to
+	// pick its inboxes there; the reply address below is in the same space for the same reason.
 	conn, err := nats.Connect(natsURL(to.Address),
 		nats.Secure(config),
+		nats.CustomInboxPrefix("_INBOX.enrol."+node),
 		nats.UserInfo("enrol."+node, secret),
 		nats.Name("mesh-host/enrol/"+node),
 		nats.Timeout(timeout),
@@ -124,7 +132,19 @@ func (a *natsAsking) Ask(ctx context.Context, request []byte, wait time.Duration
 	defer cancel()
 	// Into the stream and awaited: an enrolment the bus never accepted must fail here rather than be
 	// assumed, because the node has nothing else to go on.
-	if _, err := a.js.Publish(EnrolSubject, addressed, nats.Context(publish)); err != nil {
+	//
+	// **Once, however many times it is sent** (novox/hq 04-ISSUES/146). The client re-publishes when
+	// an acknowledgement is slow, and the mesh enrolled the machine on each copy — minting a second
+	// credential, which replaced the first, which is the one the node had already been given. The
+	// machine then reconnected for ever as a user whose password the mesh had rotated out from under
+	// it, and the controller's log said "enrolled anchor" twice in the same second.
+	//
+	// The id is the message: the same bytes carry the same id, so the stream discards the client's
+	// own retry, and a genuine second attempt — which carries a new reply address — is a different
+	// message and is let through.
+	sum := sha256.Sum256(addressed)
+	if _, err := a.js.Publish(EnrolSubject, addressed,
+		nats.MsgId(hex.EncodeToString(sum[:])), nats.Context(publish)); err != nil {
 		return nil, fmt.Errorf("cannot ask the mesh to enrol this node: %w", err)
 	}
 

internal/link/messages.go

@@ -110,6 +110,15 @@ type Report struct {
 	// and the mesh's up in its place, and where the found configuration's original was kept.
 	Tunnel *CarriedTunnel `json:"tunnel,omitempty"`
 
+	// Strays is what runs on the machine that the mesh neither wrote nor holds (novox/hq ADR
+	// 0163): containers nobody declared and nobody holds, the ones a cutover leaves behind.
+	Strays []Stray `json:"strays,omitempty"`
+
+	// Profile is what this machine can do, detected again by the apply that reports (novox/hq
+	// ADR 0161) — the same shape enrolment sends — so a capability gained or lost since enrolment,
+	// a network manager switched, reaches the mesh at the next push rather than never.
+	Profile map[string]any `json:"profile,omitempty"`
+
 	// Host is the version of the host that produced this report (novox/hq ADR 0141).
 	//
 	// Without it nothing can say a machine is behind, so "every machine current with its source"
@@ -200,6 +209,16 @@ type Held struct {
 	Changed string `json:"changed,omitempty"`
 	// Kept is where a file's original was kept.
 	Kept string `json:"kept,omitempty"`
+	// Facts is the found thing beside what the module declares — what a take compares (novox/hq
+	// ADR 0163). The same shape the host keeps; the controller reads it as data.
+	Facts map[string]any `json:"facts,omitempty"`
+}
+
+// A Stray is a container the mesh neither wrote nor holds (ADR 0163).
+type Stray struct {
+	Kind   string `json:"kind"`
+	Name   string `json:"name"`
+	Detail string `json:"detail,omitempty"`
 }
 
 // Reach is one thing reachable on the machine: a listening socket, or a published container port.

internal/profile/detectors.go

@@ -20,6 +20,14 @@ const (
 	// state: whether one IS running. Assignment needs the first.
 	CapSeat       = "seat"
 	CapPrivileged = "privileged"
+
+	// The network manager this machine runs, one capability per dialect (novox/hq ADR 0161): the
+	// uplink seat's holder declares its own, so the holder for a manager the machine does not run
+	// is refused the way any missing capability is, naming it. Active, not installed — a machine
+	// may have two of these on disk and runs one.
+	CapUplinkNetworkManager  = "uplink-networkmanager"
+	CapUplinkSystemdNetworkd = "uplink-systemd-networkd"
+	CapUplinkDhcpcd          = "uplink-dhcpcd"
 )
 
 // commandCapability is the shape most detectors take: run something, and treat a working
@@ -202,6 +210,21 @@ func Default(runner Runner) []Detector {
 			why:    "asks the kernel for interfaces — needs the module, not just the tool",
 			runner: runner,
 		},
+		commandCapability{
+			name: CapUplinkNetworkManager, command: "systemctl", args: []string{"is-active", "NetworkManager.service"},
+			why:    "asks the init whether NetworkManager is running — the dialect the uplink seat's holder must speak",
+			runner: runner,
+		},
+		commandCapability{
+			name: CapUplinkSystemdNetworkd, command: "systemctl", args: []string{"is-active", "systemd-networkd.service"},
+			why:    "asks the init whether systemd-networkd is running — the dialect the uplink seat's holder must speak",
+			runner: runner,
+		},
+		commandCapability{
+			name: CapUplinkDhcpcd, command: "systemctl", args: []string{"is-active", "dhcpcd.service"},
+			why:    "asks the init whether dhcpcd is running — the dialect the uplink seat's holder must speak",
+			runner: runner,
+		},
 	}
 }
 

internal/profile/uplink_test.go

@@ -0,0 +1,39 @@
+package profile
+
+import (
+	"context"
+	"errors"
+	"testing"
+)
+
+// The uplink seat's holder must be the dialect the machine runs (novox/hq ADR 0161): the profile
+// names the network manager found active, one capability per manager, and nothing for one that is
+// merely installed.
+func TestTheProfileNamesTheNetworkManagerThatIsRunning(t *testing.T) {
+	runner := func(_ context.Context, name string, args ...string) (string, error) {
+		if name == "systemctl" && len(args) == 2 && args[0] == "is-active" {
+			if args[1] == "NetworkManager.service" {
+				return "active\n", nil
+			}
+			return "inactive\n", errors.New("exit status 3")
+		}
+		return "", errors.New("not here")
+	}
+	var have []Detector
+	for _, d := range Default(Runner(runner)) {
+		switch d.Name() {
+		case CapUplinkNetworkManager, CapUplinkSystemdNetworkd, CapUplinkDhcpcd:
+			have = append(have, d)
+		}
+	}
+	if len(have) != 3 {
+		t.Fatalf("expected a detector per manager, found %d", len(have))
+	}
+	for _, d := range have {
+		v := d.Detect(context.Background())
+		want := d.Name() == CapUplinkNetworkManager
+		if v.Present != want {
+			t.Errorf("%s: present=%v, want %v (%s)", d.Name(), v.Present, want, v.Detail)
+		}
+	}
+}

internal/store/former_test.go

@@ -0,0 +1,29 @@
+package store
+
+import "testing"
+
+// A resource whose target moves leaves what the host wrote under the old target on record as a
+// former one, undeclared by construction, so the next apply removes it (novox/hq issue 097, ADR 0163).
+func TestARecordWhoseTargetMovedKeepsTheFormerTargetToRemove(t *testing.T) {
+	s := State{}
+	s.Record(Applied{ID: "gitea.server", Type: "container", Target: "mesh-gitea", Origin: OriginDeclared})
+	s.Record(Applied{ID: "gitea.server", Type: "container", Target: "gitea", Origin: OriginDeclared})
+	if len(s.Resources) != 2 {
+		t.Fatalf("a moved target produced %d record(s): %+v", len(s.Resources), s.Resources)
+	}
+	orphans := s.Orphans(map[string]bool{"gitea.server": true}, OriginDeclared)
+	if len(orphans) != 1 || orphans[0].Target != "mesh-gitea" || !IsFormer(orphans[0].ID) {
+		t.Fatalf("the former target is not an orphan to remove: %+v", orphans)
+	}
+	s.Forget(orphans[0].ID)
+	if len(s.Resources) != 1 || s.Resources[0].Target != "gitea" {
+		t.Fatalf("forgetting the former target touched the current one: %+v", s.Resources)
+	}
+	// The same target again is not a move; a carried record is not the host's to remove.
+	s.Record(Applied{ID: "gitea.server", Type: "container", Target: "gitea", Origin: OriginDeclared})
+	s.Record(Applied{ID: "bundle", Type: "file", Target: "/a"})
+	s.Record(Applied{ID: "bundle", Type: "file", Target: "/b"})
+	if len(s.Resources) != 2 {
+		t.Fatalf("an unmoved or carried record grew the list: %+v", s.Resources)
+	}
+}

internal/store/store.go

@@ -18,6 +18,7 @@ import (
 	"os"
 	"path/filepath"
 	"sort"
+	"strings"
 	"time"
 )
 
@@ -274,6 +275,41 @@ type Held struct {
 	// reverted: that is how a predecessor still writing is caught.
 	Changed   string    `json:"changed,omitempty"`
 	ChangedAt time.Time `json:"changed_at,omitempty"`
+	// Facts is what a take would compare: the found thing beside what the module declares
+	// (novox/hq ADR 0163). Read fresh on every apply while held, so the controller's preview
+	// speaks of the machine as it is.
+	Facts *Facts `json:"facts,omitempty"`
+}
+
+// Facts is a held thing beside what its module declares — what a take compares (ADR 0163).
+type Facts struct {
+	// A found container: the image it runs and when that image was made; the networks it is on
+	// and the other containers on each; what it mounts; what it publishes.
+	Image        string              `json:"image,omitempty"`
+	ImageCreated string              `json:"image_created,omitempty"`
+	Networks     map[string][]string `json:"networks,omitempty"`
+	Mounts       []string            `json:"mounts,omitempty"`
+	Ports        []string            `json:"ports,omitempty"`
+	// What the module declares for it, and the declared image's creation date when the image
+	// is on the machine already.
+	DeclaredImage        string   `json:"declared_image,omitempty"`
+	DeclaredImageCreated string   `json:"declared_image_created,omitempty"`
+	DeclaredPorts        []string `json:"declared_ports,omitempty"`
+	DeclaredVolumes      []string `json:"declared_volumes,omitempty"`
+	// Downgrade is true when both creation dates are known and the declared image is the older.
+	Downgrade bool `json:"downgrade,omitempty"`
+	// A found file: whether the declared content differs from what was found, and how, as lines
+	// only in the found file (-) and lines only in the declared one (+), bounded.
+	Differs    bool     `json:"differs,omitempty"`
+	Difference []string `json:"difference,omitempty"`
+}
+
+// A Stray is something running on the machine that the mesh neither wrote nor holds
+// (novox/hq ADR 0163): the answer to "what is here that nobody asked for".
+type Stray struct {
+	Kind   string `json:"kind"`
+	Name   string `json:"name"`
+	Detail string `json:"detail,omitempty"`
 }
 
 // Recorded reports whether this host has a record, of any origin, of putting something of this
@@ -462,6 +498,20 @@ func Save(path string, s State) error {
 func (s *State) Record(a Applied) {
 	for i, existing := range s.Resources {
 		if existing.ID == a.ID {
+			// A resource whose target moved leaves what the host wrote under the old target
+			// behind — a container under the old name, a file at the old path. Rewriting the
+			// record would erase the only trace of it (novox/hq issue 097, ADR 0163), so the old
+			// target stays on record as a former one, undeclared by construction, until the next
+			// apply removes it the way it removes anything the host wrote and no longer declares.
+			// What was found is held, never recorded here, and so never removed by this.
+			if originOf(existing) == OriginDeclared && existing.Target != "" && a.Target != "" &&
+				existing.Target != a.Target && existing.Type == a.Type {
+				former := existing
+				former.ID = FormerID(existing.ID, existing.Target)
+				s.Resources[i] = a
+				s.Resources = append(s.Resources, former)
+				return
+			}
 			s.Resources[i] = a
 			return
 		}
@@ -469,6 +519,13 @@ func (s *State) Record(a Applied) {
 	s.Resources = append(s.Resources, a)
 }
 
+// FormerID names the record of a resource's former target: the resource's id and the target it
+// had, so the record is distinct from the current one and is never what a declaration names.
+func FormerID(id, target string) string { return id + "@former:" + target }
+
+// IsFormer says whether a record names a former target.
+func IsFormer(id string) bool { return strings.Contains(id, "@former:") }
+
 // Forget drops a resource from what the node owns.
 func (s *State) Forget(id string) {
 	kept := s.Resources[:0]