Merge pull request 'Make buildah's runtime directory before every buildah run, so mesh-build-image's health does not fail for want of it (issue 1884)' (#456) from fix/1884-runtime-dir into main

The look made <store>/xdg only after `buildah --version`, which refuses first
when its XDG_RUNTIME_DIR is missing: the directory was never made on ace.

checks/owned/main.go

@@ -11,13 +11,23 @@
 //     another module, after ${dir:<id>} is resolved within each module and both homes are read as one root.
 //     Archives are not containers for this rule. This holds for ~/.ssh what checks/sshdir held (ADR 0415 §6).
 //
-//     go run . <catalogue root>
+//  5. a directory that is, lies inside or holds a directory a system package owns under /var/lib, or any other
+//     resource inside one (issue 1841: pacman's state directory, placed with "place": ".", was /var/lib/pacman, the
+//     package manager's own database directory). A placed directory is resolved as the mesh resolves it with the
+//     default data root: "." is /var/lib/<module>, "mesh" /var/lib/mesh/<module>, neither /var/lib/<module>/<id>.
+//     The system directories are checks/owned/system, captured from a machine (pacman -Qo, /usr/lib/tmpfiles.d);
+//     checks/owned/system-known names the exceptions still to fix, by module, resource and issue. That list only
+//     shrinks: an entry that no longer collides is refused, and with -base one the trunk's copy does not hold.
+//
+//     go run . [-base <trunk's system-known>] <catalogue root>
 //
 // Exits 1 on a finding.
 package main
 
 import (
 	"encoding/json"
+	"errors"
+	"flag"
 	"fmt"
 	"os"
 	"path"
@@ -27,6 +37,12 @@ import (
 	"strings"
 )
 
+// The lists of rule 5, relative to the catalogue's root.
+const (
+	SystemList  = "checks/owned/system"
+	SystemKnown = "checks/owned/system-known"
+)
+
 // Home is the one root both machine homes are read as.
 const Home = "${home}"
 
@@ -43,9 +59,9 @@ type Finding struct {
 }
 
 type resource struct {
-	ID, Type, Path, Unknown string
-	Knows                   []string
-	HasKnows                bool
+	ID, Type, Path, Unknown, Place string
+	Knows                          []string
+	HasKnows                       bool
 }
 
 type parsed struct {
@@ -65,6 +81,7 @@ func load(file string) (*parsed, error) {
 			ID      string   `json:"id"`
 			Type    string   `json:"type"`
 			Path    string   `json:"path"`
+			Place   string   `json:"place"`
 			Unknown *string  `json:"unknown"`
 			Knows   []string `json:"knows"`
 		} `json:"resources"`
@@ -81,7 +98,7 @@ func load(file string) (*parsed, error) {
 		out.Module = filepath.Base(filepath.Dir(file))
 	}
 	for _, r := range m.Resources {
-		x := resource{ID: r.ID, Type: r.Type, Path: r.Path, Knows: r.Knows, HasKnows: r.Knows != nil}
+		x := resource{ID: r.ID, Type: r.Type, Path: r.Path, Place: r.Place, Knows: r.Knows, HasKnows: r.Knows != nil}
 		if r.Unknown != nil {
 			x.Unknown = *r.Unknown
 			if x.Unknown == "" {
@@ -143,14 +160,23 @@ type declared struct {
 }
 
 // Check reads every manifest under root/modules and answers what it refuses.
-func Check(root string) ([]Finding, error) {
+func Check(root string, base []string) ([]Finding, error) {
 	files, err := filepath.Glob(filepath.Join(root, "modules", "*", "module.json"))
 	if err != nil {
 		return nil, err
 	}
 	sort.Strings(files)
+	system, err := readSystem(filepath.Join(root, SystemList))
+	if err != nil {
+		return nil, err
+	}
+	known, err := readLines(filepath.Join(root, SystemKnown))
+	if err != nil && !errors.Is(err, os.ErrNotExist) {
+		return nil, err
+	}
 	var out []Finding
 	var paths []declared
+	collided := map[string]bool{}
 	type container struct{ module, path string }
 	var containers []container
 	for _, file := range files {
@@ -170,6 +196,7 @@ func Check(root string) ([]Finding, error) {
 				dirs[r.ID] = "/placed/" + m.Module + "/" + r.ID
 			}
 		}
+		out = append(out, inSystem(m, system, known, collided)...)
 		for _, r := range m.Resources {
 			p := norm(r.Path, dirs)
 			if p != "" {
@@ -212,6 +239,28 @@ func Check(root string) ([]Finding, error) {
 			}
 		}
 	}
+	for _, k := range known {
+		if !collided[k] {
+			module, id, _ := strings.Cut(k, " ")
+			id, _, _ = strings.Cut(id, " ")
+			out = append(out, Finding{5, module, id, fmt.Sprintf("is listed in %s, and no longer lies in a system "+
+				"package's directory: take the line out, so the list only shrinks", SystemKnown)})
+		}
+	}
+	if base != nil {
+		held := map[string]bool{}
+		for _, b := range base {
+			held[b] = true
+		}
+		for _, k := range known {
+			if !held[k] {
+				module, id, _ := strings.Cut(k, " ")
+				id, _, _ = strings.Cut(id, " ")
+				out = append(out, Finding{5, module, id, fmt.Sprintf("is a new line in %s, which the trunk's copy "+
+					"does not hold: a module's directory is placed outside a system package's, never listed", SystemKnown)})
+			}
+		}
+	}
 	for _, d := range paths {
 		for _, c := range containers {
 			if c.module != d.module && (d.path == c.path || strings.HasPrefix(d.path, c.path+"/")) {
@@ -222,21 +271,140 @@ func Check(root string) ([]Finding, error) {
 	return out, nil
 }
 
-func main() {
-	root := "."
-	if len(os.Args) > 1 {
-		root = os.Args[1]
+// systemDir is one directory a system package owns, and what says so.
+type systemDir struct{ Path, Source string }
+
+// readLines is a list's lines, without comments and blank lines.
+func readLines(file string) ([]string, error) {
+	raw, err := os.ReadFile(file)
+	if err != nil {
+		return nil, err
 	}
-	found, err := Check(root)
+	var lines []string
+	for _, line := range strings.Split(string(raw), "\n") {
+		if line = strings.TrimSpace(line); line != "" && !strings.HasPrefix(line, "#") {
+			lines = append(lines, line)
+		}
+	}
+	return lines, nil
+}
+
+// readSystem is the list of system directories: "<absolute path> <package>: <how it was read>" per line. Absent or
+// empty, the check fails: a list that says nothing would let every module through.
+func readSystem(file string) ([]systemDir, error) {
+	lines, err := readLines(file)
+	if err != nil {
+		return nil, fmt.Errorf("rule 5 reads the system packages' directories from %s: %w", file, err)
+	}
+	if len(lines) == 0 {
+		return nil, fmt.Errorf("%s names no system package's directory, so rule 5 would pass everything", file)
+	}
+	var out []systemDir
+	for _, line := range lines {
+		p, source, _ := strings.Cut(line, " ")
+		if !strings.HasPrefix(p, "/var/lib/") || strings.TrimSpace(source) == "" {
+			return nil, fmt.Errorf("%s: %q is not \"/var/lib/<directory> <package>: <how it was read>\"", file, line)
+		}
+		out = append(out, systemDir{path.Clean(p), strings.TrimSpace(source)})
+	}
+	return out, nil
+}
+
+// placedAt is where the mesh places a pathless directory with the default data root (mesh-sdk catalogue dirsFor).
+func placedAt(module string, r resource) string {
+	switch r.Place {
+	case ".":
+		return "/var/lib/" + module
+	case "mesh":
+		return "/var/lib/mesh/" + module
+	}
+	return "/var/lib/" + module + "/" + r.ID
+}
+
+// inSystem is rule 5 for one module: each resource whose resolved path collides with a system package's directory,
+// unless system-known lists it (then it is marked collided, so a stale line is found).
+func inSystem(m *parsed, system []systemDir, known []string, collided map[string]bool) []Finding {
+	real := map[string]string{}
+	for _, r := range m.Resources {
+		if r.Type == "directory" && r.Path == "" && r.ID != "" {
+			real[r.ID] = placedAt(m.Module, r)
+		}
+	}
+	for _, r := range m.Resources {
+		if r.ID != "" && r.Path != "" {
+			real[r.ID] = r.Path
+		}
+	}
+	var out []Finding
+	for _, r := range m.Resources {
+		p := ""
+		if r.Path != "" {
+			p = norm(r.Path, real)
+		} else if r.Type == "directory" {
+			p = real[r.ID]
+		}
+		if !strings.HasPrefix(p, "/") {
+			continue
+		}
+		for _, s := range system {
+			inside := p == s.Path || strings.HasPrefix(p, s.Path+"/")
+			holds := r.Type == "directory" && strings.HasPrefix(s.Path, p+"/")
+			if !inside && !holds {
+				continue
+			}
+			listed := ""
+			for _, k := range known {
+				if strings.HasPrefix(k, m.Module+" "+r.ID+" ") || k == m.Module+" "+r.ID {
+					listed = k
+				}
+			}
+			if listed != "" {
+				collided[listed] = true
+				break
+			}
+			how := "is or lies inside"
+			if holds {
+				how = "holds"
+			}
+			out = append(out, Finding{5, m.Module, r.ID, fmt.Sprintf("resolves to %q, which %s %s, the directory of the "+
+				"system package %s; place it under /var/lib/mesh/%s (\"place\": \"mesh\") or a path of its own", p, how,
+				s.Path, s.Source, m.Module)})
+			break
+		}
+	}
+	return out
+}
+
+func main() {
+	baseFile := flag.String("base", "", "the trunk's copy of "+SystemKnown+": a line it does not hold is refused")
+	flag.Parse()
+	root := "."
+	if flag.NArg() > 0 {
+		root = flag.Arg(0)
+	}
+	var base []string
+	if *baseFile != "" {
+		lines, err := readLines(*baseFile)
+		if err != nil {
+			fmt.Fprintln(os.Stderr, err)
+			os.Exit(1)
+		}
+		base = append([]string{}, lines...)
+	}
+	found, err := Check(root, base)
 	if err != nil {
 		fmt.Fprintln(os.Stderr, err)
 		os.Exit(1)
 	}
 	for _, f := range found {
-		fmt.Printf("%s: %s: %s (rule %d, novox/hq ADR 0422 §8, issue 1024)\n", f.Module, f.ID, f.Why, f.Rule)
+		cite := "novox/hq ADR 0422 §8, issue 1024"
+		if f.Rule == 5 {
+			cite = "issue 1841"
+		}
+		fmt.Printf("%s: %s: %s (rule %d, %s)\n", f.Module, f.ID, f.Why, f.Rule, cite)
 	}
 	if len(found) > 0 {
 		os.Exit(1)
 	}
-	fmt.Println("owned paths: every directory and archive says how it treats unknown files; no module declares inside another's directory")
+	fmt.Println("owned paths: every directory and archive says how it treats unknown files; no module declares inside another's directory, or in a system package's")
 }

checks/owned/main_test.go

@@ -20,7 +20,10 @@ func manifest(t *testing.T, root, module, body string) {
 
 func check(t *testing.T, root string) []Finding {
 	t.Helper()
-	found, err := Check(root)
+	if _, err := os.Stat(filepath.Join(root, SystemList)); os.IsNotExist(err) {
+		lists(t, root, "/var/lib/pacman pacman: pacman -Qo\n", "")
+	}
+	found, err := Check(root, nil)
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -35,6 +38,20 @@ func only(t *testing.T, found []Finding, rule int, module, id string) {
 	}
 }
 
+// lists writes the catalogue's list of system directories and its known exceptions.
+func lists(t *testing.T, root, system, known string) {
+	t.Helper()
+	if err := os.MkdirAll(filepath.Join(root, "checks", "owned"), 0o755); err != nil {
+		t.Fatal(err)
+	}
+	if err := os.WriteFile(filepath.Join(root, SystemList), []byte(system), 0o644); err != nil {
+		t.Fatal(err)
+	}
+	if err := os.WriteFile(filepath.Join(root, SystemKnown), []byte(known), 0o644); err != nil {
+		t.Fatal(err)
+	}
+}
+
 func dir(id, path, rest string) string {
 	return `{"id":"` + id + `","type":"directory","path":"` + path + `"` + rest + `}`
 }
@@ -145,3 +162,87 @@ func TestPlacedDirectoriesOfTwoModulesAreTheirOwn(t *testing.T) {
 		t.Fatalf("refused %+v", found)
 	}
 }
+
+// 1841/AC18: a module's directory that resolves to a /var/lib directory a system package owns, lies inside one or
+// holds one, is refused, whether placed (place ".", or by default beneath the module's own) or stated; a placed
+// directory saying place "mesh" lies under /var/lib/mesh and passes (issue 1841: pacman's state was /var/lib/pacman).
+func TestADirectoryOfASystemPackageIsRefused(t *testing.T) {
+	system := "/var/lib/pacman pacman: pacman -Qo\n/var/lib/systemd/coredump systemd: tmpfiles.d/systemd.conf\n"
+	for name, resources := range map[string][]string{
+		"placed-own":     {`{"id":"state","type":"directory","place":".","unknown":"program"}`},
+		"placed-beneath": {`{"id":"coredump","type":"directory","unknown":"program"}`},
+		"stated-inside":  {dir("d", "/var/lib/pacman/keeper", `,"unknown":"program"`)},
+		"stated-holding": {dir("d", "/var/lib/systemd", `,"unknown":"program"`)},
+		"file-inside": {`{"id":"state","type":"directory","place":"mesh","unknown":"program"}`,
+			`{"id":"f","type":"file","path":"/var/lib/pacman/keeper.json"}`},
+	} {
+		module := map[string]string{"placed-own": "pacman", "placed-beneath": "systemd"}[name]
+		if module == "" {
+			module = "keeper"
+		}
+		root := t.TempDir()
+		lists(t, root, system, "")
+		manifest(t, root, module, mod(module, resources...))
+		found := check(t, root)
+		if len(found) != 1 || found[0].Rule != 5 || found[0].Module != module ||
+			!strings.Contains(found[0].Why, "/var/lib/") || !strings.Contains(found[0].Why, "package") {
+			t.Errorf("%s: found %+v; want one finding of rule 5 for %s naming the path and the package", name, found, module)
+		}
+	}
+	root := t.TempDir()
+	lists(t, root, system, "")
+	manifest(t, root, "pacman", mod("pacman",
+		`{"id":"state","type":"directory","place":"mesh","unknown":"program"}`,
+		`{"id":"f","type":"file","path":"${dir:state}/keeper.json"}`,
+		dir("other", "/var/lib/pacman-other", `,"unknown":"program"`)))
+	if found := check(t, root); len(found) != 0 {
+		t.Fatalf("a directory under /var/lib/mesh/pacman was refused: %+v", found)
+	}
+}
+
+// 1841/AC18: a known exception passes; one that no longer collides is refused, so the list only shrinks; one the trunk's
+// copy does not hold is refused; and an absent list of system directories fails the check rather than passing it.
+func TestKnownSystemExceptionsOnlyShrink(t *testing.T) {
+	system := "/var/lib/systemd systemd: tmpfiles.d/systemd.conf\n"
+	known := "# comment\nsystemd state issue 1873\n"
+	root := t.TempDir()
+	lists(t, root, system, known)
+	manifest(t, root, "systemd", mod("systemd", `{"id":"state","type":"directory","place":".","unknown":"program"}`))
+	if found := check(t, root); len(found) != 0 {
+		t.Fatalf("a known exception was refused: %+v", found)
+	}
+	if found, err := Check(root, []string{"systemd state issue 1873"}); err != nil || len(found) != 0 {
+		t.Fatalf("a known exception held by the trunk was refused: %+v %v", found, err)
+	}
+	if found, err := Check(root, []string{}); err != nil || len(found) != 1 || found[0].Rule != 5 {
+		t.Fatalf("an exception the trunk does not hold passed: %+v %v", found, err)
+	}
+
+	manifest(t, root, "systemd", mod("systemd", `{"id":"state","type":"directory","place":"mesh","unknown":"program"}`))
+	only(t, check(t, root), 5, "systemd", "state")
+
+	root = t.TempDir()
+	manifest(t, root, "a", mod("a"))
+	if err := os.MkdirAll(filepath.Join(root, "checks", "owned"), 0o755); err != nil {
+		t.Fatal(err)
+	}
+	if err := os.WriteFile(filepath.Join(root, SystemList), []byte("# nothing\n"), 0o644); err != nil {
+		t.Fatal(err)
+	}
+	if _, err := Check(root, nil); err == nil {
+		t.Fatal("an empty list of system directories passed")
+	}
+}
+
+// 1841/AC18: the catalogue as it stands passes rule 5 with its own lists.
+func TestTheCatalogueKeepsOutOfSystemDirectories(t *testing.T) {
+	found, err := Check("../..", nil)
+	if err != nil {
+		t.Fatal(err)
+	}
+	for _, f := range found {
+		if f.Rule == 5 {
+			t.Errorf("%s: %s: %s", f.Module, f.ID, f.Why)
+		}
+	}
+}

checks/owned/system

@@ -0,0 +1,23 @@
+# The directories under /var/lib that a system package owns (rule 5 of checks/owned, issue 1841). A module's
+# directory, placed or stated, may not be one of these, lie inside one or hold one: the package's program and the
+# package manager keep their own files there, and the node-engine would judge, chmod or chown the directory.
+#
+# One line per directory: "<path> <package>: <how it was read>". Captured on the workstation on 2026-10-22, through
+# the mesh: pacman's own database by `pacman -Qo` (pacman_owns), the rest from the `d`, `D` and `Q` lines of
+# /usr/lib/tmpfiles.d (node-reads.search for "/var/lib/"). A directory found to belong to a package is added here.
+/var/lib/pacman pacman: pacman -Qo /var/lib/pacman/ (pacman 7.1.0)
+/var/lib/alsa alsa-utils: tmpfiles.d/alsa-utils.conf
+/var/lib/colord colord: tmpfiles.d/colord.conf
+/var/lib/containers podman: tmpfiles.d/podman.conf
+/var/lib/dbus dbus: tmpfiles.d/dbus.conf
+/var/lib/geoclue geoclue: tmpfiles.d/geoclue.conf
+/var/lib/lastlog util-linux: tmpfiles.d/lastlog2.conf
+/var/lib/libuuid util-linux: tmpfiles.d/uuidd.conf
+/var/lib/machines systemd: tmpfiles.d/systemd-nspawn.conf
+/var/lib/openvpn/chroot networkmanager-openvpn: tmpfiles.d/nm-openvpn-tmpfiles.conf
+/var/lib/portables systemd: tmpfiles.d/portables.conf
+/var/lib/postgres postgresql: tmpfiles.d/postgresql.conf
+/var/lib/private systemd: tmpfiles.d/systemd.conf
+/var/lib/rpcbind rpcbind: tmpfiles.d/rpcbind.conf
+/var/lib/systemd systemd: tmpfiles.d/systemd.conf
+/var/lib/tpm2-tss/system/keystore tpm2-tss: tmpfiles.d/tpm2-tss-fapi.conf

checks/owned/system-known

@@ -0,0 +1,5 @@
+# Modules whose directory lies in a system package's directory today (rule 5 of checks/owned, issue 1841), each with
+# the issue that moves it out: "<module> <resource id> issue <number>". This list only shrinks: a line whose module
+# no longer collides is refused, and so is a line the trunk's copy does not hold.
+postgres state issue 1873
+systemd state issue 1873

merge-check.sh

@@ -48,7 +48,8 @@
 #   10. the mail-store seat (novox/hq ADR 0378 §3, issue 800): no manifest but modules/mesh-mail claims it.
 #   11. owned paths (novox/hq ADR 0422 §8, issue 1024; it holds ~/.ssh for ssh-client as ADR 0415 §6 asked):
 #      every directory and archive says `unknown` (move-out, module or program) and a valid `knows`; `move-out`
-#      only under a home; and no module declares a path inside a directory of another module.
+#      only under a home; no module declares a path inside a directory of another module; and none is, lies in or
+#      holds a directory a system package owns under /var/lib (checks/owned/system, issue 1841).
 #      checks/sshdir (ADR 0415 §6) stays while main runs it; it goes under issue 1035 once main runs checks/owned.
 #   12. the image builder (novox/hq ADR 0487 §3, issue 1704): only modules/buildah provides rootless-image-build.
 #   13. the image's place (novox/hq ADR 0487 §1, issue 1707): every image builds from a Dockerfile in its own module's directory.
@@ -71,8 +72,19 @@ set -eu
 # ~/.ssh (novox/hq ADR 0415 §6): only ssh-client may name a path under it. Main's merge check runs this line, so
 # checks/sshdir stays until main runs checks/owned; it goes under issue 1035.
 (cd checks/sshdir && go test -count=1 . && go run . ../..)
-# Owned paths (novox/hq ADR 0422 §8): unknown files named per directory; no path inside another module's directory.
-(cd checks/owned && go test -count=1 . && go run . ../..)
+# Owned paths (novox/hq ADR 0422 §8): unknown files named per directory; no path inside another module's directory;
+# none in a system package's directory under /var/lib (issue 1841), the known exceptions only shrinking: judged
+# against the trunk's copy of checks/owned/system-known at the merge base; a trunk without one is the list's first copy.
+owned_base=""
+if merge_base=$(git merge-base HEAD "origin/${MESH_CHECK_BASE:-main}" 2>/dev/null); then
+	if git cat-file -e "$merge_base:checks/owned/system-known" 2>/dev/null; then
+		owned_base=$(mktemp)
+		git show "$merge_base:checks/owned/system-known" >"$owned_base"
+	fi
+else
+	echo "NOT COMPARED WITH THE TRUNK: no merge base with origin/${MESH_CHECK_BASE:-main}; checks/owned/system-known is held to the list it was first written with"
+fi
+(cd checks/owned && go test -count=1 . && if [ -n "$owned_base" ]; then go run . -base "$owned_base" ../..; else go run . ../..; fi)
 # The secrets (novox/hq issue 342): a password is not a setting, so no setting can replace the vault's. The
 # known list only shrinks: judged against the trunk's copy at the merge base, a line it does not hold is refused.
 secrets_base=""

modules/mesh-build-image/cmd/mesh-build-image/module.go

@@ -4,8 +4,6 @@ import (
 	"context"
 	"fmt"
 	"net/http"
-	"os"
-	"path/filepath"
 	"time"
 
 	"git.novox.be/novox/mesh-sdk/go/buildstep"
@@ -60,6 +58,11 @@ type Look struct {
 // missing is a *buildstep.Refusal naming it, so a step ends refused and the health says the same.
 func (m *Module) look(ctx context.Context) (Look, error) {
 	l := Look{Account: m.Account}
+	// The runtime directory comes first: buildah refuses before anything else when its XDG_RUNTIME_DIR is not there
+	// (issue 1884), so a look that made it only after `buildah --version` never made it at all.
+	if err := m.ensureRuntimeDir(); err != nil {
+		return l, &buildstep.Refusal{Text: err.Error()}
+	}
 	var err error
 	if l.Buildah, err = m.buildahVersion(ctx); err != nil {
 		return l, &buildstep.Refusal{Text: err.Error()}
@@ -67,11 +70,6 @@ func (m *Module) look(ctx context.Context) (Look, error) {
 	if l.UIDs, l.GIDs, err = m.ranges(); err != nil {
 		return l, &buildstep.Refusal{Text: err.Error(), Have: l.Buildah}
 	}
-	for _, d := range []string{m.Store, filepath.Join(m.Store, "xdg")} {
-		if err := os.MkdirAll(d, 0o700); err != nil {
-			return l, err
-		}
-	}
 	if err := m.userNamespace(ctx); err != nil {
 		return l, &buildstep.Refusal{Text: err.Error(), Have: l.Buildah}
 	}

modules/mesh-build-image/cmd/mesh-build-image/probe.go

@@ -111,6 +111,25 @@ func (m *Module) storeFlags() []string {
 // env is what buildah is given beyond the base environment: a runtime directory of its own inside the store, so
 // nothing is read from the account's runtime directory, and no registry credential file anywhere (the module has none
 // and REGISTRY_AUTH_FILE is never set).
+//
+// Every call makes the runtime directory first if it is not there (issue 1884): a directory removed after the last look
+// is made again before buildah runs. A failure to make it is not lost: buildah then names the directory in its own
+// error, and the next look refuses with it.
 func (m *Module) env() []string {
-	return []string{"XDG_RUNTIME_DIR=" + filepath.Join(m.Store, "xdg")}
+	_ = m.ensureRuntimeDir()
+	return []string{"XDG_RUNTIME_DIR=" + m.runtimeDir()}
+}
+
+// runtimeDir is buildah's runtime directory, inside the store.
+func (m *Module) runtimeDir() string { return filepath.Join(m.Store, "xdg") }
+
+// ensureRuntimeDir makes the store and the runtime directory inside it, 0700 and under the module's own account (the
+// process runs as it), when they are not there; it changes nothing that is.
+func (m *Module) ensureRuntimeDir() error {
+	for _, d := range []string{m.Store, m.runtimeDir()} {
+		if err := os.MkdirAll(d, 0o700); err != nil {
+			return fmt.Errorf("buildah's runtime directory %s cannot be made: %w", m.runtimeDir(), err)
+		}
+	}
+	return nil
 }

modules/mesh-build-image/cmd/mesh-build-image/runtimedir_test.go

@@ -0,0 +1,83 @@
+package main
+
+import (
+	"context"
+	"os"
+	"path/filepath"
+	"strings"
+	"testing"
+
+	"git.novox.be/novox/mesh-sdk/go/forgekey"
+	"git.novox.be/novox/mesh-sdk/go/health"
+)
+
+// buildahLike refuses as buildah does when the XDG_RUNTIME_DIR it is given is not there (seen on ace, issue 1884):
+// "lstat <dir>: no such file or directory", before it does anything else.
+func buildahLike(t *testing.T, run forgekey.Runner, seen *[]string) forgekey.Runner {
+	t.Helper()
+	return func(ctx context.Context, env []string, name string, args ...string) forgekey.Ran {
+		if name == "buildah" {
+			for _, e := range env {
+				dir, ok := strings.CutPrefix(e, "XDG_RUNTIME_DIR=")
+				if !ok {
+					continue
+				}
+				if _, err := os.Lstat(dir); err != nil {
+					*seen = append(*seen, "missing")
+					return forgekey.Ran{Status: 125, Stderr: "Error: lstat " + dir + ": no such file or directory\n"}
+				}
+				*seen = append(*seen, "present")
+			}
+		}
+		return run(ctx, env, name, args...)
+	}
+}
+
+// 1884/AC1: given a store directory that exists without its runtime directory, when the health is looked at, then the
+// module makes the runtime directory (0700) before it runs buildah, and the health is healthy.
+func TestHealthMakesTheRuntimeDirectoryBeforeBuildah(t *testing.T) {
+	f := newFake(t)
+	m := moduleWith(t, f, newStates())
+	var seen []string
+	m.Run = buildahLike(t, m.Run, &seen)
+	xdg := filepath.Join(m.Store, "xdg")
+	if _, err := os.Stat(xdg); !os.IsNotExist(err) {
+		t.Fatalf("the test needs a store without its runtime directory: %v", err)
+	}
+	a := m.Health(context.Background())
+	if a.State != health.StateHealthy || !a.Healthy {
+		t.Fatalf("health = %+v, want healthy", a)
+	}
+	st, err := os.Stat(xdg)
+	if err != nil {
+		t.Fatalf("the runtime directory was not made: %v", err)
+	}
+	if st.Mode().Perm() != 0o700 || !st.IsDir() {
+		t.Errorf("the runtime directory is %v, want a directory 0700", st.Mode())
+	}
+	for _, s := range seen {
+		if s != "present" {
+			t.Fatalf("buildah ran without its runtime directory: %v", seen)
+		}
+	}
+}
+
+// 1884/AC2: given a module whose runtime directory was removed after its last look, when a build step runs buildah, then
+// the runtime directory is made again before buildah runs.
+func TestEveryBuildahRunMakesTheRuntimeDirectoryAgain(t *testing.T) {
+	f := newFake(t)
+	m := moduleWith(t, f, newStates())
+	var seen []string
+	m.Run = buildahLike(t, m.Run, &seen)
+	if err := m.Check(context.Background()); err != nil {
+		t.Fatal(err)
+	}
+	if err := os.RemoveAll(filepath.Join(m.Store, "xdg")); err != nil {
+		t.Fatal(err)
+	}
+	seen = nil
+	m.remove("localhost/x:y")
+	if len(seen) != 1 || seen[0] != "present" {
+		t.Fatalf("buildah's runs saw their runtime directory %v, want [present]", seen)
+	}
+}

modules/mesh-provisioner-client/cmd/mesh-provisioner-client/client.go

@@ -120,7 +120,7 @@ type Client struct {
 	// Now dates the reports; nil is time.Now.
 	Now func() time.Time
 	// SocketUp wakes the client when the node-engine's write socket is made again (watchSocket); nil never does.
-	// A module whose write failed for want of the socket is filled again then (issue 1165), and nothing else is.
+	// A module whose write failed is filled again then (issue 1165, issue 1873), and nothing else is.
 	SocketUp <-chan struct{}
 
 	// watchBound watches a provider's bucket of entries for this machine's keys, once per run (consumers.go); set by
@@ -150,7 +150,8 @@ type state struct {
 	// of the consumers left out of one of its files.
 	providing map[string]bool
 	leftOut   map[string]string
-	// unplaced is a module whose last fill failed for want of the node-engine's write socket (issue 1165).
+	// unplaced is a module whose last fill failed, for want of the node-engine's write socket (issue 1165) or by the
+	// engine's own refusal (issue 1873): filled again when the socket is made again.
 	unplaced map[string]bool
 	// bound is each provider's bucket of entries this client watches, by key: this machine's consumers' entries alone;
 	// boundReady is a bucket whose current entries are all read, and boundUsers the modules filled from each.
@@ -705,9 +706,10 @@ func (c *Client) reconcile(ctx context.Context, kvs map[string]jetstream.KeyValu
 			err = errFill(a)
 		}
 		if err != nil {
-			if socketAbsent(err) {
-				s.unplaced[module] = true
-			}
+			// Filled again when a node-engine makes its socket again: one gone (issue 1165), or one that refused for a
+			// reason of its own, which a newer engine may write (issue 1873: "is a directory", what a container
+			// runtime left at the path, cleared by the engine that followed).
+			s.unplaced[module] = true
 			failed = append(failed, fmt.Sprintf("%s: %v", f.Path, err))
 			continue
 		}

modules/mesh-provisioner-client/cmd/mesh-provisioner-client/socket_integration_test.go

@@ -106,3 +106,38 @@ func TestWatchSocketWakesWhenTheSocketIsMadeAndWhenItsDirectoryReturns(t *testin
 	defer l.Close()
 	heard("the directory and socket back")
 }
+
+// Issue 1873: a fill the node-engine refused for a reason of its own (on ace, "read …/superuser.secret: is a
+// directory", what a container runtime had left there) is tried again when a node-engine makes its socket again, as a
+// newer engine may write what the older could not. Before, only a fill that failed for want of the socket was, so
+// ace's postgres stayed unplaced after the engine that cures it was delivered, and its old failure was said every 30 s.
+func TestNatsAFillTheEngineFailedIsTriedWhenTheSocketReturns(t *testing.T) {
+	b := startBus(t)
+	heard := b.listen(t)
+	e := newEngine(t, map[string]string{dunstrc: "owned"})
+	if err := os.MkdirAll(e.at(dunstrc), 0o755); err != nil {
+		t.Fatal(err)
+	}
+	stop := e.listen(t)
+	b.config(t, "dunst", "font-size", "13")
+	b.assign(t, "dunst", dunst(t))
+	aClient(t, b, e, t.TempDir())
+
+	eventually(t, "the engine's failure is said", func() bool {
+		r, _ := heard.last("dunst")
+		return r.Status == StatusFailed && strings.Contains(r.Reason, "is a directory")
+	})
+	// The node-engine replaces itself with one that clears what the runtime left.
+	stop()
+	if err := os.Remove(e.at(dunstrc)); err != nil {
+		t.Fatal(err)
+	}
+	e.listen(t)
+	eventually(t, "dunstrc is written by the new engine", func() bool {
+		return strings.Contains(e.read(t, dunstrc), "Monospace 13")
+	})
+	eventually(t, "and the report says applied", func() bool {
+		r, _ := heard.last("dunst")
+		return r.Status == StatusApplied
+	})
+}

modules/pacman/cmd/pacman-tools/keeper_manifest_test.go

@@ -83,7 +83,7 @@ func TestTheKeeperIsAProcessUnderItsOwnAccountWithABusAccountOfItsOwn(t *testing
 		t.Errorf("the bus account is the keeper's own secret, owned by its account: %v", secrets)
 	}
 	state := m.resource(t, "state")
-	if state["type"] != "directory" || state["place"] != "." || state["unknown"] == nil {
+	if state["type"] != "directory" || state["place"] != "mesh" || state["unknown"] == nil {
 		t.Errorf("the state directory: %v", state)
 	}
 	order := map[string]int{}
@@ -211,3 +211,37 @@ func TestUpgradeOrderIsATrustedListOfTheMesh(t *testing.T) {
 		t.Error("a value falls back only to a key of its own type (ADR 0348 §4)")
 	}
 }
+
+// 1841/AC17: the keeper's state directory is the mesh's directory for the module (place "mesh", <data root>/mesh/pacman),
+// never place "." or a placement by default: for this module both resolve under /var/lib/pacman, the package manager's
+// own database directory (issue 1841: the node-engine used it as found and reported it unhealthy, and wrote keeper.json
+// into it). What the keeper and its root helper keep there is still named through ${dir:state}.
+func TestTheStateDirectoryIsOutsideThePackageManagersOwn(t *testing.T) {
+	m := rawManifest(t)
+	resources, _ := m["resources"].([]any)
+	var state map[string]any
+	for _, x := range resources {
+		if r, _ := x.(map[string]any); r["id"] == "state" {
+			state = r
+		}
+	}
+	if state == nil || state["type"] != "directory" {
+		t.Fatalf("no state directory: %v", state)
+	}
+	if state["place"] != "mesh" || state["path"] != nil {
+		t.Fatalf("the state directory says place %v and path %v; it is placed \"mesh\" with no path, so it resolves to "+
+			"/var/lib/mesh/pacman and not into /var/lib/pacman", state["place"], state["path"])
+	}
+	raw, err := os.ReadFile(filepath.Join(moduleDir, "module.json"))
+	if err != nil {
+		t.Fatal(err)
+	}
+	if bytes.Contains(raw, []byte("/var/lib/pacman")) {
+		t.Fatal("the manifest names /var/lib/pacman")
+	}
+	for _, want := range []string{"${dir:state}/keeper.json", "${dir:state}/broker-keeper.secret", RootSocketPath} {
+		if !bytes.Contains(raw, []byte(want)) {
+			t.Errorf("the manifest no longer names %s", want)
+		}
+	}
+}

modules/pacman/cmd/pacman-tools/main.go

@@ -248,12 +248,12 @@ func tools(m *Machine) []stdio.Tool {
 			Name: "pacman_upgrades",
 			Description: "Every full upgrade and rollback of every node, from the bus (ADR 0508 §1): each run's node, kind, what started it, " +
 				"its round, when it began and ended, its outcome (refused, finished, failed or running) and whether its after-upgrade check passed; " +
-				"narrowed to a node and to days, newest first. With a node and a run, that run whole, every step with its time.",
+				"narrowed to a node and to days, newest first. With a run, that run whole, every step with its time: the node's named, else this one's.",
 			Input: schema(map[string]any{
 				"node":  map[string]any{"type": "string", "description": "only this node's runs"},
 				"from":  sinceArg,
 				"until": map[string]any{"type": "string", "description": "a day, YYYY-MM-DD, the last one listed"},
-				"run":   map[string]any{"type": "string", "description": "one run, by its id, with node"},
+				"run":   map[string]any{"type": "string", "description": "one run, by its id: of node, else of this node"},
 				"limit": limitArg(50, 1000),
 			}),
 			Run: func(args map[string]any) (any, error) {
@@ -269,6 +269,11 @@ func tools(m *Machine) []stdio.Tool {
 				if err != nil {
 					return nil, err
 				}
+				if v[3] != "" && v[0] == "" {
+					// An address naming the machine has its node taken out of the arguments (the console):
+					// the run is this machine's (issue 1841).
+					v[0] = thisNode()
+				}
 				return ListUpgrades(upgradeState(StateRuns), v[0], v[1], v[2], v[3], n)
 			},
 		},

modules/pacman/cmd/pacman-tools/rollback.go

@@ -228,7 +228,7 @@ func (u *Upgrades) StartRollback(of string, removeAdded bool, ask string) (Run,
 		if o.Run.Run == r.Run.Run {
 			return r.Run, fmt.Errorf("run %s of %s is there already: one run a second", o.Run.Run, u.Node)
 		}
-		if !ended(o.Run) && o.From != FromLog {
+		if holdsTheDatabase(o.Run) {
 			return r.Run, u.refuse(r, fmt.Sprintf("run %s is still going (its last step is %s): one run at a time", o.Run.Run, lastStep(o.Run)))
 		}
 	}

modules/pacman/cmd/pacman-tools/stale_run_test.go

@@ -0,0 +1,115 @@
+package main
+
+// A run read from pacman's log, or a run whose transaction ended, never holds a new run back (issue 1841, the
+// refusal of 2026-10-22 22:00 on the control-node: "run 20220123T194900Z is still going (its last step is finished): one
+// run at a time"); and pacman_upgrades reads one run whole at an address that names the machine.
+
+import (
+	"strings"
+	"testing"
+	"time"
+)
+
+// installLogHead is the first twelve lines of the control-node's /var/log/pacman.log, captured 2026-10-22 22:10
+// with node-reads.read: the install's `pacman -Syu` with nothing to do, which became run 20220123T194900Z, its
+// last step finished at the moment it began (pacman_upgrades there, 2026-10-22: from log, outcome finished,
+// began 2022-01-23T19:49:00Z, ended 2022-01-23T20:49:00+01:00).
+const installLogHead = "[2022-01-23T20:49:00+0100] [PACMAN] Running 'pacman -Syu'\n" +
+	"[2022-01-23T20:49:00+0100] [PACMAN] synchronizing package lists\n" +
+	"[2022-01-23T20:49:00+0100] [PACMAN] starting full system upgrade\n" +
+	"[2022-01-23T20:50:45+0100] [PACMAN] Running 'pacman -S nano'\n" +
+	"[2022-01-23T20:50:49+0100] [ALPM] transaction started\n" +
+	"[2022-01-23T20:50:50+0100] [ALPM] installed nano (6.0-1)\n" +
+	"[2022-01-23T20:50:50+0100] [ALPM] transaction completed\n" +
+	"[2022-01-23T20:50:50+0100] [ALPM] running '30-systemd-update.hook'...\n" +
+	"[2022-01-23T20:55:31+0100] [PACMAN] Running 'pacman -S docker'\n" +
+	"[2022-01-23T20:55:36+0100] [ALPM] transaction started\n" +
+	"[2022-01-23T20:55:36+0100] [ALPM] installed bridge-utils (1.7.1-1)\n" +
+	"[2022-01-23T20:55:36+0100] [ALPM] installed libtool (2.4.6+42+gb88cebd5-16)\n"
+
+// 1841/AC20: given the run read from the control-node's log, when an upgrade is asked, then it starts.
+func TestARunReadFromTheLogIsHistoryAndNeverHoldsAnAsk(t *testing.T) {
+	k := newKeeperBed(t)
+	past := PastUpgrades("node-a", installLogHead)
+	if len(past) != 1 || past[0].Run != "20220123T194900Z" || steps(past[0]) != "started finished" || past[0].From != FromLog {
+		t.Fatalf("the captured log reads as the record the control-node holds: %+v", past)
+	}
+	if _, err := k.runs.Create(NodeKey("node-a", past[0].Run), past[0]); err != nil {
+		t.Fatal(err)
+	}
+	if _, err := k.u.StartUpgrade(FromAsk, "", "a1"); err != nil {
+		t.Fatal(err)
+	}
+	var r Run
+	k.runs.value("node-a.20261004T120000Z", &r)
+	if lastStep(r) == StepRefused || len(k.root.started) != 1 {
+		t.Errorf("a run read from the log held the ask back: %s %+v", steps(r), r.Steps)
+	}
+}
+
+// 1841/AC21: given a run the mesh ran whose last step is finished, failed or refused (no after-upgrade check
+// yet, no end time of the run itself), when another run would start, then the earlier one does not hold it;
+// a run whose transaction may still go on (no step, recorded, checked before, started) does.
+func TestARunWhoseTransactionEndedNeverHoldsTheNext(t *testing.T) {
+	at := time.Date(2026, 10, 22, 20, 0, 0, 0, time.UTC)
+	for last, holds := range map[string]bool{
+		StepFinished: false, StepFailed: false, StepRefused: false, StepCheckedAfter: false,
+		"": true, StepRecorded: true, StepCheckedBefore: true, StepStarted: true,
+	} {
+		r := Run{Node: "node-a", Run: "20261022T200000Z", Kind: RunUpgrade, From: FromAsk}
+		if last != "" {
+			r.Steps = []Step{{Step: last, At: at}}
+		}
+		if got := holdsTheDatabase(r); got != holds {
+			t.Errorf("last step %q: holds %v, want %v", last, got, holds)
+		}
+		r.From = FromLog
+		if holdsTheDatabase(r) {
+			t.Errorf("a run read from the log, last step %q, holds the next", last)
+		}
+	}
+
+	k := newKeeperBed(t)
+	done := Run{Node: "node-a", Run: "20261004T110000Z", Kind: RunUpgrade, From: FromAsk,
+		Steps: []Step{{Step: StepStarted, At: k.now}, {Step: StepFinished, At: k.now}}}
+	if _, err := k.runs.Create(NodeKey("node-a", done.Run), done); err != nil {
+		t.Fatal(err)
+	}
+	if _, err := k.u.StartUpgrade(FromAsk, "", "a1"); err != nil {
+		t.Fatal(err)
+	}
+	var r Run
+	k.runs.value("node-a.20261004T120000Z", &r)
+	if lastStep(r) == StepRefused {
+		t.Errorf("a finished run held the next: %+v", r.Steps)
+	}
+}
+
+// 1841/AC22: given an address that names the machine (the console takes `node` out of the arguments), when
+// pacman_upgrades is asked for one run, then that machine's run is answered whole.
+func TestPacmanUpgradesReadsOneRunOfThisNodeWithoutANode(t *testing.T) {
+	runs := newBucket()
+	past := PastUpgrades("node-a", installLogHead)[0]
+	if _, err := runs.Create(NodeKey("node-a", past.Run), past); err != nil {
+		t.Fatal(err)
+	}
+	savedState, savedNode := upgradeState, thisNode
+	upgradeState = func(string) Bucket { return runs }
+	thisNode = func() string { return "node-a" }
+	defer func() { upgradeState, thisNode = savedState, savedNode }()
+	for _, tool := range tools(machine(nil, 1000)) {
+		if tool.Name != "pacman_upgrades" {
+			continue
+		}
+		out, err := tool.Run(map[string]any{"run": past.Run})
+		if err != nil {
+			t.Fatalf("one run without a node: %v", err)
+		}
+		whole := out.(map[string]any)["run"].(Run)
+		if whole.Node != "node-a" || steps(whole) != "started finished" || !strings.Contains(whole.Steps[1].Why, "no transaction") {
+			t.Errorf("one run whole: %+v", whole)
+		}
+		return
+	}
+	t.Fatal("no pacman_upgrades")
+}

modules/pacman/cmd/pacman-tools/transaction.go

@@ -63,6 +63,22 @@ func ended(r Run) bool {
 	return false
 }
 
+// holdsTheDatabase says whether a run holds a new run back (one run at a time, ADR 0508 §8): only a run the
+// mesh ran whose transaction may still go on. A run read from pacman's log is history (ADR 0508 §1), and a run
+// whose last step is finished, failed, refused or checked after has no transaction left: its after-upgrade
+// check, still to be written by Follow, reads and changes nothing (issue 1841: every run read from the log
+// ended at finished and held every ask back).
+func holdsTheDatabase(r Run) bool {
+	if r.From == FromLog {
+		return false
+	}
+	switch lastStep(r) {
+	case StepFinished, StepFailed, StepRefused, StepCheckedAfter:
+		return false
+	}
+	return true
+}
+
 // ownRuns are the node's runs, oldest first, each with the revision of its key.
 func (u *Upgrades) ownRuns() ([]openRun, error) {
 	keys, err := u.Runs.Keys()
@@ -117,7 +133,7 @@ func (u *Upgrades) startUpgrade(r *openRun) error {
 		if o.Run.Run == r.Run.Run {
 			return fmt.Errorf("run %s of %s is there already: one run a second", o.Run.Run, u.Node)
 		}
-		if !ended(o.Run) {
+		if holdsTheDatabase(o.Run) {
 			return u.refuse(r, fmt.Sprintf("run %s is still going (its last step is %s): one run at a time", o.Run.Run, lastStep(o.Run)))
 		}
 	}

modules/pacman/module.json

@@ -147,7 +147,7 @@
       "id": "state",
       "type": "directory",
       "mode": "0711",
-      "place": ".",
+      "place": "mesh",
       "unknown": "program"
     },
     {

modules/postgres/README.md

@@ -119,7 +119,8 @@ what is declared, refusing secrets, taking back what is no longer declared, and
 
 Each directory or archive this module declares says how it treats a file it did not write (ADR 0422, ADR 0416).
 
-- `${dir:state}`: everything in it is the program's; the mesh moves nothing out (ADR 0422 §2).
+- `${dir:data}` (`/var/lib/mesh/<module>`): everything in it is the program's; the mesh moves nothing out (ADR 0422 §2).
+- `${dir:state}`: the package's own directory, declared for one delivery with the package's owner and mode so the node-engine gives it back (issue 1873); the module keeps nothing there.
 - `${dir:grants}`: everything in it is the program's; the mesh moves nothing out (ADR 0422 §2).
 - `/var/lib/mesh-store`: everything in it is the program's; the mesh moves nothing out (ADR 0422 §2).
 - `${dir:store-data}/dumps`: everything in it is the program's; the mesh moves nothing out (ADR 0422 §2).

modules/postgres/cmd/postgres-provider/manifest_test.go

@@ -0,0 +1,94 @@
+package main
+
+// The module's directories (novox/hq issue 1873): its state directory said place ".", which is /var/lib/postgres,
+// the postgresql package's own (tmpfiles.d/postgresql.conf: postgres, 0700), and its grants directory, placed by
+// default, lay inside it; the node-engine gave /var/lib/postgres to the operator's account. What the module keeps
+// moves to the mesh's directory for it, and for one delivery the record "state" states the package's owner and mode,
+// so the node-engine, which takes a directory it recorded at the same path under the same id as its own, gives it
+// back. The store's data is not touched: it is /var/lib/mesh-store, as before.
+
+import (
+	"encoding/json"
+	"os"
+	"reflect"
+	"strings"
+	"testing"
+)
+
+func postgresManifest(t *testing.T) (map[string]map[string]any, map[string]any) {
+	t.Helper()
+	raw, err := os.ReadFile("../../module.json")
+	if err != nil {
+		t.Fatal(err)
+	}
+	if strings.Contains(string(raw), "${dir:state}") {
+		t.Errorf("the manifest still keeps something in ${dir:state}, which is /var/lib/postgres")
+	}
+	var m map[string]any
+	if err := json.Unmarshal(raw, &m); err != nil {
+		t.Fatal(err)
+	}
+	out := map[string]map[string]any{}
+	list, _ := m["resources"].([]any)
+	for _, x := range list {
+		r, _ := x.(map[string]any)
+		out[r["id"].(string)] = r
+	}
+	return out, m
+}
+
+// 1873/AC2: secrets, consumers and grants are kept in <data root>/mesh/postgres; "state" gives /var/lib/postgres back
+// to postgres, 0700; the store's data and dumps are as they were.
+func TestTheModuleKeepsItsFilesOutsideThePackagesDirectory(t *testing.T) {
+	rs, m := postgresManifest(t)
+	data := rs["data"]
+	if data == nil || data["type"] != "directory" || data["place"] != "mesh" || data["path"] != nil || data["mode"] != "0700" {
+		t.Fatalf("the module's directory is placed \"mesh\" with no path, 0700 (/var/lib/mesh/postgres): %v", data)
+	}
+	if g := rs["grants"]; g == nil || g["path"] != "${dir:data}/grants" || g["place"] != nil {
+		t.Errorf("grants lies in the module's directory: %v", g)
+	}
+	if c := rs["consumers"]; c == nil || c["path"] != "${dir:data}/consumers.json" {
+		t.Errorf("consumers.json lies in the module's directory: %v", c)
+	}
+	own, _ := m["own-secrets"].(map[string]any)
+	if own["superuser"] != "${dir:data}/superuser.secret" || own["reader"] != "${dir:data}/reader.secret" {
+		t.Errorf("the own secrets lie in the module's directory: %v", own)
+	}
+	state := rs["state"]
+	if state == nil || state["type"] != "directory" || state["path"] != "/var/lib/postgres" || state["owner"] != "postgres" ||
+		state["mode"] != "0700" || state["place"] != nil {
+		t.Errorf("state gives /var/lib/postgres back as postgresql declares it, postgres 0700: %v", state)
+	}
+
+	// The store's data, its dumps and how the container reads them: exactly as before.
+	if s := rs["store-data"]; !reflect.DeepEqual(s, map[string]any{"id": "store-data", "type": "directory",
+		"path": "/var/lib/mesh-store", "mode": "0700", "owner": "999:70", "unknown": "program"}) {
+		t.Errorf("store-data changed: %v", s)
+	}
+	if d := rs["dumps"]; !reflect.DeepEqual(d, map[string]any{"id": "dumps", "type": "directory",
+		"path": "${dir:store-data}/dumps", "mode": "0700", "owner": "999:70", "unknown": "program"}) {
+		t.Errorf("dumps changed: %v", d)
+	}
+	server := rs["server"]
+	if !reflect.DeepEqual(server["volumes"], []any{"/var/lib/mesh-store:/var/lib/postgresql/data",
+		"${dir:data}/superuser.secret:/run/secrets/superuser:ro"}) {
+		t.Errorf("the container's volumes: %v", server["volumes"])
+	}
+	if env, _ := server["env"].(map[string]any); env["PGDATA"] != "/var/lib/postgresql/data/pgdata" {
+		t.Errorf("PGDATA changed: %v", env)
+	}
+	build, _ := m["build"].(map[string]any)
+	artifacts, _ := build["artifacts"].([]any)
+	env := artifacts[0].(map[string]any)["env"].(map[string]any)
+	for key, want := range map[string]string{
+		"MESH_PROVISION_PASSWORD_FILE":       "${dir:data}/superuser.secret",
+		"MESH_POSTGRES_READER_PASSWORD_FILE": "${dir:data}/reader.secret",
+		"MESH_CONSUMERS_FILE":                "${dir:data}/consumers.json",
+		"MESH_RECEIVES":                      "${dir:grants}/mesh.json",
+	} {
+		if env[key] != want {
+			t.Errorf("%s is %v, not %s", key, env[key], want)
+		}
+	}
+}

modules/postgres/module.json

@@ -61,8 +61,8 @@
     "postgres-database": "${dir:grants}"
   },
   "own-secrets": {
-    "superuser": "${dir:state}/superuser.secret",
-    "reader": "${dir:state}/reader.secret"
+    "superuser": "${dir:data}/superuser.secret",
+    "reader": "${dir:data}/reader.secret"
   },
   "data": {
     "own": [
@@ -93,22 +93,31 @@
   },
   "resources": [
     {
-      "id": "state",
+      "id": "data",
       "type": "directory",
       "mode": "0700",
-      "place": ".",
+      "place": "mesh",
+      "unknown": "program"
+    },
+    {
+      "id": "state",
+      "type": "directory",
+      "path": "/var/lib/postgres",
+      "owner": "postgres",
+      "mode": "0700",
       "unknown": "program"
     },
     {
       "id": "grants",
       "type": "directory",
+      "path": "${dir:data}/grants",
       "mode": "0700",
       "unknown": "program"
     },
     {
       "id": "consumers",
       "type": "file",
-      "path": "${dir:state}/consumers.json",
+      "path": "${dir:data}/consumers.json",
       "mode": "0600",
       "template": "files/consumers.json"
     },
@@ -146,7 +155,7 @@
       ],
       "volumes": [
         "/var/lib/mesh-store:/var/lib/postgresql/data",
-        "${dir:state}/superuser.secret:/run/secrets/superuser:ro"
+        "${dir:data}/superuser.secret:/run/secrets/superuser:ro"
       ]
     },
     {
@@ -169,10 +178,10 @@
         ],
         "env": {
           "MESH_PROVISION_POSTGRES": "postgres://postgres@127.0.0.1:${port:5432}/postgres?sslmode=disable",
-          "MESH_PROVISION_PASSWORD_FILE": "${dir:state}/superuser.secret",
+          "MESH_PROVISION_PASSWORD_FILE": "${dir:data}/superuser.secret",
           "MESH_RECEIVES": "${dir:grants}/mesh.json",
-          "MESH_POSTGRES_READER_PASSWORD_FILE": "${dir:state}/reader.secret",
-          "MESH_CONSUMERS_FILE": "${dir:state}/consumers.json"
+          "MESH_POSTGRES_READER_PASSWORD_FILE": "${dir:data}/reader.secret",
+          "MESH_CONSUMERS_FILE": "${dir:data}/consumers.json"
         }
       },
       {

modules/systemd/README.md

@@ -6,4 +6,5 @@ The `systemd` module of the mesh catalogue: installs the package `systemd`; clai
 
 Each directory or archive this module declares says how it treats a file it did not write (ADR 0422, ADR 0416).
 
-- `${dir:state}`: everything in it is the program's; the mesh moves nothing out (ADR 0422 §2).
+- `${dir:data}` (`/var/lib/mesh/<module>`): everything in it is the program's; the mesh moves nothing out (ADR 0422 §2).
+- `${dir:state}`: the package's own directory, declared for one delivery with the package's owner and mode so the node-engine gives it back (issue 1873); the module keeps nothing there.

modules/systemd/cmd/systemd-tools/manifest_test.go

@@ -0,0 +1,52 @@
+package main
+
+// The module's directories (novox/hq issue 1873): its state directory said place ".", which is /var/lib/systemd,
+// systemd's own directory (tmpfiles.d/systemd.conf: d /var/lib/systemd 0755 root root); the node-engine gave it to
+// the operator's account, mode 0700, on every machine. What the tools keep moves to the mesh's directory for the
+// module, and for one delivery the record "state" states the package's owner and mode, so the node-engine, which
+// takes a directory it recorded at the same path under the same id as its own, gives it back.
+
+import (
+	"encoding/json"
+	"os"
+	"testing"
+)
+
+func manifestResources(t *testing.T) (map[string]map[string]any, map[string]any) {
+	t.Helper()
+	raw, err := os.ReadFile("../../module.json")
+	if err != nil {
+		t.Fatal(err)
+	}
+	var m map[string]any
+	if err := json.Unmarshal(raw, &m); err != nil {
+		t.Fatal(err)
+	}
+	out := map[string]map[string]any{}
+	list, _ := m["resources"].([]any)
+	for _, x := range list {
+		r, _ := x.(map[string]any)
+		out[r["id"].(string)] = r
+	}
+	return out, m
+}
+
+// 1873/AC1: the tools' record is kept in <data root>/mesh/systemd; "state" gives /var/lib/systemd back to root, 0755.
+func TestTheToolsKeepTheirRecordOutsideSystemdsOwnDirectory(t *testing.T) {
+	rs, m := manifestResources(t)
+	data := rs["data"]
+	if data == nil || data["type"] != "directory" || data["place"] != "mesh" || data["path"] != nil {
+		t.Fatalf("the tools' directory is placed \"mesh\" with no path (/var/lib/mesh/systemd): %v", data)
+	}
+	build, _ := m["build"].(map[string]any)
+	artifacts, _ := build["artifacts"].([]any)
+	env := artifacts[0].(map[string]any)["env"].(map[string]any)
+	if env["MESH_SYSTEMD_STATE"] != "${dir:data}" {
+		t.Errorf("MESH_SYSTEMD_STATE is %v, not ${dir:data}", env["MESH_SYSTEMD_STATE"])
+	}
+	state := rs["state"]
+	if state == nil || state["type"] != "directory" || state["path"] != "/var/lib/systemd" || state["owner"] != "root" ||
+		state["mode"] != "0755" || state["place"] != nil {
+		t.Errorf("state gives /var/lib/systemd back as systemd declares it, root 0755: %v", state)
+	}
+}

modules/systemd/module.json

@@ -41,7 +41,7 @@
           "systemd-tools"
         ],
         "env": {
-          "MESH_SYSTEMD_STATE": "${dir:state}"
+          "MESH_SYSTEMD_STATE": "${dir:data}"
         }
       }
     ]
@@ -53,10 +53,18 @@
       "package": "systemd"
     },
     {
-      "id": "state",
+      "id": "data",
       "type": "directory",
       "mode": "0700",
-      "place": ".",
+      "place": "mesh",
+      "unknown": "program"
+    },
+    {
+      "id": "state",
+      "type": "directory",
+      "path": "/var/lib/systemd",
+      "owner": "root",
+      "mode": "0755",
       "unknown": "program"
     }
   ]