diff --git a/CODEMAP.md b/CODEMAP.md
index 42ce3766c..e679a7cf4 100644
--- a/CODEMAP.md
+++ b/CODEMAP.md
@@ -220,6 +220,8 @@ Frequently Touched Files (by topic)
 - Migrations: `internal/entity/migrate/*`
 - Workers: `internal/workers/*`
 - Cluster: `internal/service/cluster/*`
+  - Theme support: `internal/service/cluster/theme/version.go` exposes `DetectVersion`, used by bootstrap, CLI, and API handlers to compare portal vs node theme revisions (prefers `fs.VersionTxtFile`, falls back to `app.js` mtime).
+  - Registration sanitizes `AppName`, `AppVersion`, and `Theme` with `clean.TypeUnicode`; `cluster.RegisterResponse` now includes a `Theme` hint when the portal has a newer bundle so nodes can decide whether to download immediately.
 - Headers: `pkg/service/http/header/*`
 
 Downloads (CLI) & yt-dlp helpers
diff --git a/internal/api/cluster_nodes_register.go b/internal/api/cluster_nodes_register.go
index caa6f6de3..688b92bb1 100644
--- a/internal/api/cluster_nodes_register.go
+++ b/internal/api/cluster_nodes_register.go
@@ -17,6 +17,7 @@ import (
 	"github.com/photoprism/photoprism/internal/service/cluster"
 	"github.com/photoprism/photoprism/internal/service/cluster/provisioner"
 	reg "github.com/photoprism/photoprism/internal/service/cluster/registry"
+	"github.com/photoprism/photoprism/internal/service/cluster/theme"
 	"github.com/photoprism/photoprism/pkg/clean"
 	"github.com/photoprism/photoprism/pkg/rnd"
 	"github.com/photoprism/photoprism/pkg/service/http/header"
@@ -33,7 +34,7 @@ var RegisterRequireClientSecret = true
 //	@Tags		Cluster
 //	@Accept		json
 //	@Produce	json
-//	@Param		request				body		object	true	"registration payload (NodeName required; optional: NodeRole, Labels, AdvertiseUrl, SiteUrl; to authorize UUID/name changes include ClientID+ClientSecret; rotation: RotateDatabase, RotateSecret)"
+//	@Param		request				body		object	true	"registration payload (NodeName required; optional: NodeRole, Labels, AdvertiseUrl, SiteUrl, AppName, AppVersion, Theme; to authorize UUID/name changes include ClientID+ClientSecret; rotation: RotateDatabase, RotateSecret)"
 //	@Success	200,201				{object}	cluster.RegisterResponse
 //	@Failure	400,401,403,409,429	{object}	i18n.Response
 //	@Router		/api/v1/cluster/nodes/register [post]
@@ -77,6 +78,10 @@ func ClusterNodesRegister(router *gin.RouterGroup) {
 			return
 		}
 
+		appName := clean.TypeUnicode(req.AppName)
+		appVersion := clean.TypeUnicode(req.AppVersion)
+		nodeTheme := clean.TypeUnicode(req.Theme)
+
 		// If an existing ClientID is provided, require the corresponding client secret for verification.
 		if RegisterRequireClientSecret && req.ClientID != "" {
 			if !rnd.IsUID(req.ClientID, entity.ClientUID) {
@@ -139,6 +144,11 @@ func ClusterNodesRegister(router *gin.RouterGroup) {
 			return
 		}
 
+		portalTheme := ""
+		if t, err := theme.DetectVersion(conf.PortalThemePath()); err == nil {
+			portalTheme = t
+		}
+
 		// Try to find existing node.
 		if n, _ := regy.FindByName(name); n != nil {
 			// If caller attempts to change UUID by name without proving client secret, block with 409.
@@ -159,6 +169,15 @@ func ClusterNodesRegister(router *gin.RouterGroup) {
 			if s := normalizeSiteURL(req.SiteUrl); s != "" {
 				n.SiteUrl = s
 			}
+			if appName != "" {
+				n.AppName = appName
+			}
+			if appVersion != "" {
+				n.AppVersion = appVersion
+			}
+			if nodeTheme != "" {
+				n.Theme = nodeTheme
+			}
 			// Apply UUID changes for existing node: if a UUID was requested and differs, or if none exists yet.
 			if requestedUUID != "" {
 				oldUUID := n.UUID
@@ -239,6 +258,10 @@ func ClusterNodesRegister(router *gin.RouterGroup) {
 				AlreadyProvisioned: n.Database != nil && n.Database.Name != "",
 			}
 
+			if portalTheme != "" && (nodeTheme == "" || nodeTheme != portalTheme) {
+				resp.Theme = portalTheme
+			}
+
 			if n.Database != nil {
 				resp.Database = cluster.RegisterDatabase{Host: conf.DatabaseHost(), Port: conf.DatabasePort(), Name: n.Database.Name, User: n.Database.User, Driver: provisioner.DatabaseDriver, RotatedAt: n.Database.RotatedAt}
 			}
@@ -258,10 +281,13 @@ func ClusterNodesRegister(router *gin.RouterGroup) {
 		// New node (client UID will be generated in registry.Put).
 		n := &reg.Node{
 			Node: cluster.Node{
-				Name:   name,
-				Role:   clean.TypeLowerDash(req.NodeRole),
-				UUID:   requestedUUID,
-				Labels: req.Labels,
+				Name:       name,
+				Role:       clean.TypeLowerDash(req.NodeRole),
+				UUID:       requestedUUID,
+				Labels:     req.Labels,
+				AppName:    appName,
+				AppVersion: appVersion,
+				Theme:      nodeTheme,
 			},
 		}
 
@@ -318,6 +344,10 @@ func ClusterNodesRegister(router *gin.RouterGroup) {
 			AlreadyProvisioned: shouldProvisionDB,
 		}
 
+		if portalTheme != "" && (nodeTheme == "" || nodeTheme != portalTheme) {
+			resp.Theme = portalTheme
+		}
+
 		if shouldProvisionDB {
 			resp.Database = cluster.RegisterDatabase{Host: conf.DatabaseHost(), Port: conf.DatabasePort(), Name: creds.Name, User: creds.User, Driver: provisioner.DatabaseDriver, Password: creds.Password, DSN: creds.DSN, RotatedAt: creds.RotatedAt}
 		}
@@ -334,23 +364,31 @@ func ClusterNodesRegister(router *gin.RouterGroup) {
 // Rules: require http/https scheme, non-empty host, <=255 chars; lowercase host.
 func normalizeSiteURL(u string) string {
 	u = strings.TrimSpace(u)
+
 	if u == "" {
 		return ""
 	}
+
 	if len(u) > 255 {
 		return ""
 	}
+
 	parsed, err := url.Parse(u)
+
 	if err != nil {
 		return ""
 	}
+
 	if parsed.Scheme != "http" && parsed.Scheme != "https" {
 		return ""
 	}
+
 	if parsed.Host == "" {
 		return ""
 	}
+
 	parsed.Host = strings.ToLower(parsed.Host)
+
 	return parsed.String()
 }
 
@@ -358,19 +396,24 @@ func normalizeSiteURL(u string) string {
 // and requires https for non-local hosts. http is allowed only for localhost/127.0.0.1/::1.
 func validateAdvertiseURL(u string) bool {
 	parsed, err := url.Parse(strings.TrimSpace(u))
+
 	if err != nil || parsed.Scheme == "" || parsed.Host == "" {
 		return false
 	}
+
 	host := strings.ToLower(parsed.Hostname())
+
 	if parsed.Scheme == "https" {
 		return true
 	}
+
 	if parsed.Scheme == "http" {
 		if host == "localhost" || host == "127.0.0.1" || host == "::1" {
 			return true
 		}
 		return false
 	}
+
 	return false
 }
 
@@ -378,17 +421,23 @@ func buildJWKSURL(conf *config.Config) string {
 	if conf == nil {
 		return "/.well-known/jwks.json"
 	}
+
 	path := conf.BaseUri("/.well-known/jwks.json")
+
 	if path == "" {
 		path = "/.well-known/jwks.json"
 	}
+
 	if !strings.HasPrefix(path, "/") {
 		path = "/" + path
 	}
+
 	site := strings.TrimRight(conf.SiteUrl(), "/")
+
 	if site == "" {
 		return path
 	}
+
 	return site + path
 }
 
diff --git a/internal/api/cluster_nodes_register_test.go b/internal/api/cluster_nodes_register_test.go
index 5d0c73a39..f2f5c630c 100644
--- a/internal/api/cluster_nodes_register_test.go
+++ b/internal/api/cluster_nodes_register_test.go
@@ -5,6 +5,8 @@ import (
 	"encoding/json"
 	"net/http"
 	"net/http/httptest"
+	"os"
+	"path/filepath"
 	"testing"
 	"time"
 
@@ -15,6 +17,7 @@ import (
 	"github.com/photoprism/photoprism/internal/service/cluster"
 	"github.com/photoprism/photoprism/internal/service/cluster/provisioner"
 	reg "github.com/photoprism/photoprism/internal/service/cluster/registry"
+	"github.com/photoprism/photoprism/pkg/fs"
 	"github.com/photoprism/photoprism/pkg/rnd"
 )
 
@@ -262,6 +265,38 @@ func TestClusterNodesRegister(t *testing.T) {
 			assert.NotEmpty(t, n.UUID)
 		}
 	})
+	t.Run("ThemeHintProvided", func(t *testing.T) {
+		app, router, conf := NewApiTest()
+		conf.Options().NodeRole = cluster.RolePortal
+		conf.Options().JoinToken = cluster.ExampleJoinToken
+		ClusterNodesRegister(router)
+
+		themeDir := conf.PortalThemePath()
+		assert.NoError(t, os.MkdirAll(themeDir, fs.ModeDir))
+		assert.NoError(t, os.WriteFile(filepath.Join(themeDir, fs.AppJsFile), []byte("// app\n"), fs.ModeFile))
+		assert.NoError(t, os.WriteFile(filepath.Join(themeDir, fs.VersionTxtFile), []byte(" 2.0.0\n"), fs.ModeFile))
+		t.Cleanup(func() { _ = os.RemoveAll(themeDir) })
+
+		body := `{"NodeName":"pp-node-theme","Theme":"1.0.0"}`
+		r := AuthenticatedRequestWithBody(app, http.MethodPost, "/api/v1/cluster/nodes/register", body, cluster.ExampleJoinToken)
+		assert.Equal(t, http.StatusCreated, r.Code)
+		assert.Equal(t, "2.0.0", gjson.Get(r.Body.String(), "Theme").String())
+		cleanupRegisterProvisioning(t, conf, r)
+
+		regy, err := reg.NewClientRegistryWithConfig(conf)
+		assert.NoError(t, err)
+		node, err := regy.FindByName("pp-node-theme")
+		assert.NoError(t, err)
+		if assert.NotNil(t, node) {
+			assert.Equal(t, "1.0.0", node.Theme)
+		}
+
+		body = `{"NodeName":"pp-node-theme","Theme":"2.0.0"}`
+		r2 := AuthenticatedRequestWithBody(app, http.MethodPost, "/api/v1/cluster/nodes/register", body, cluster.ExampleJoinToken)
+		assert.Equal(t, http.StatusOK, r2.Code)
+		assert.False(t, gjson.Get(r2.Body.String(), "Theme").Exists())
+		cleanupRegisterProvisioning(t, conf, r2)
+	})
 }
 
 func cleanupRegisterProvisioning(t *testing.T, conf *config.Config, r *httptest.ResponseRecorder) {
diff --git a/internal/api/cluster_summary.go b/internal/api/cluster_summary.go
index 2a376f9cc..57cd3c3ec 100644
--- a/internal/api/cluster_summary.go
+++ b/internal/api/cluster_summary.go
@@ -10,6 +10,7 @@ import (
 	"github.com/photoprism/photoprism/internal/photoprism/get"
 	"github.com/photoprism/photoprism/internal/service/cluster"
 	reg "github.com/photoprism/photoprism/internal/service/cluster/registry"
+	"github.com/photoprism/photoprism/internal/service/cluster/theme"
 	"github.com/photoprism/photoprism/pkg/service/http/header"
 )
 
@@ -44,12 +45,18 @@ func ClusterSummary(router *gin.RouterGroup) {
 		}
 
 		nodes, _ := regy.List()
+		themeVersion := ""
+
+		if v, err := theme.DetectVersion(conf.PortalThemePath()); err == nil {
+			themeVersion = v
+		}
 
 		c.JSON(http.StatusOK, cluster.SummaryResponse{
 			UUID:        conf.ClusterUUID(),
 			ClusterCIDR: conf.ClusterCIDR(),
 			Nodes:       len(nodes),
 			Database:    cluster.DatabaseInfo{Driver: conf.DatabaseDriverName(), Host: conf.DatabaseHost(), Port: conf.DatabasePort()},
+			Theme:       themeVersion,
 			Time:        time.Now().UTC().Format(time.RFC3339),
 		})
 	})
diff --git a/internal/api/cluster_theme.go b/internal/api/cluster_theme.go
index a0956f5ee..26e200059 100644
--- a/internal/api/cluster_theme.go
+++ b/internal/api/cluster_theme.go
@@ -9,8 +9,12 @@ import (
 	"github.com/gin-gonic/gin"
 
 	"github.com/photoprism/photoprism/internal/auth/acl"
+	"github.com/photoprism/photoprism/internal/config"
+	"github.com/photoprism/photoprism/internal/entity"
 	"github.com/photoprism/photoprism/internal/event"
 	"github.com/photoprism/photoprism/internal/photoprism/get"
+	reg "github.com/photoprism/photoprism/internal/service/cluster/registry"
+	"github.com/photoprism/photoprism/internal/service/cluster/theme"
 	"github.com/photoprism/photoprism/pkg/clean"
 	"github.com/photoprism/photoprism/pkg/fs"
 	"github.com/photoprism/photoprism/pkg/service/http/header"
@@ -33,6 +37,8 @@ func ClusterGetTheme(router *gin.RouterGroup) {
 
 		// Optional IP-based allowance via ClusterCIDR.
 		refID := "-"
+		var session *entity.Session
+
 		if cidr := conf.ClusterCIDR(); cidr != "" {
 			if _, ipnet, err := net.ParseCIDR(cidr); err == nil {
 				if ip := net.ParseIP(clientIp); ip != nil && ipnet.Contains(ip) {
@@ -49,6 +55,7 @@ func ClusterGetTheme(router *gin.RouterGroup) {
 				return
 			}
 			refID = s.RefID
+			session = s
 		}
 
 		/*
@@ -93,6 +100,12 @@ func ClusterGetTheme(router *gin.RouterGroup) {
 
 		event.AuditDebug([]string{clientIp, "session %s", string(acl.ResourceCluster), "theme", "download", "creating theme archive from %s"}, refID, clean.Log(themePath))
 
+		if version, err := theme.DetectVersion(themePath); err == nil {
+			updateNodeThemeVersion(conf, session, version, clientIp, refID)
+		} else {
+			event.AuditDebug([]string{clientIp, "session %s", string(acl.ResourceCluster), "theme", "version", "%s"}, refID, clean.Error(err))
+		}
+
 		// Add response headers.
 		AddDownloadHeader(c, "theme.zip")
 		AddContentTypeHeader(c, header.ContentTypeZip)
@@ -162,3 +175,62 @@ func ClusterGetTheme(router *gin.RouterGroup) {
 		}
 	})
 }
+
+// updateNodeThemeVersion persists the reported theme version for the active
+// node when the request is authenticated as a cluster client.
+func updateNodeThemeVersion(conf *config.Config, session *entity.Session, version, clientIP, refID string) {
+	if conf == nil || session == nil {
+		return
+	}
+
+	normalized := clean.TypeUnicode(version)
+
+	if normalized == "" {
+		return
+	}
+
+	client := session.GetClient()
+
+	if client == nil || client.ClientUID == "" {
+		return
+	}
+
+	regy, err := reg.NewClientRegistryWithConfig(conf)
+
+	if err != nil {
+		event.AuditDebug([]string{clientIP, "session %s", string(acl.ResourceCluster), "theme", "metadata", "registry", "%s"}, refID, clean.Error(err))
+		return
+	}
+
+	var node *reg.Node
+
+	if client.NodeUUID != "" {
+		if n, err := regy.Get(client.NodeUUID); err == nil {
+			node = n
+		}
+	}
+
+	if node == nil {
+		if n, err := regy.FindByClientID(client.ClientUID); err == nil {
+			node = n
+		}
+	}
+
+	if node == nil {
+		event.AuditDebug([]string{clientIP, "session %s", string(acl.ResourceCluster), "theme", "metadata", "node not found"}, refID)
+		return
+	}
+
+	if node.Theme == normalized {
+		return
+	}
+
+	node.Theme = normalized
+
+	if err = regy.Put(node); err != nil {
+		event.AuditWarn([]string{clientIP, "session %s", string(acl.ResourceCluster), "theme", "metadata", "%s"}, refID, clean.Error(err))
+		return
+	}
+
+	event.AuditDebug([]string{clientIP, "session %s", string(acl.ResourceCluster), "theme", "metadata", "updated"}, refID)
+}
diff --git a/internal/api/cluster_theme_test.go b/internal/api/cluster_theme_test.go
index ac5c8701a..00db12e3c 100644
--- a/internal/api/cluster_theme_test.go
+++ b/internal/api/cluster_theme_test.go
@@ -11,8 +11,11 @@ import (
 
 	"github.com/stretchr/testify/assert"
 
+	"github.com/photoprism/photoprism/internal/entity"
 	"github.com/photoprism/photoprism/internal/service/cluster"
+	reg "github.com/photoprism/photoprism/internal/service/cluster/registry"
 	"github.com/photoprism/photoprism/pkg/fs"
+	"github.com/photoprism/photoprism/pkg/rnd"
 	"github.com/photoprism/photoprism/pkg/service/http/header"
 )
 
@@ -58,6 +61,7 @@ func TestClusterGetTheme(t *testing.T) {
 		// Visible files
 		assert.NoError(t, os.WriteFile(filepath.Join(tempTheme, "app.js"), []byte("console.log('ok')\n"), fs.ModeFile))
 		assert.NoError(t, os.WriteFile(filepath.Join(tempTheme, "style.css"), []byte("body{}\n"), fs.ModeFile))
+		assert.NoError(t, os.WriteFile(filepath.Join(tempTheme, fs.VersionTxtFile), []byte(" 1.0.0\n"), fs.ModeFile))
 		assert.NoError(t, os.WriteFile(filepath.Join(tempTheme, "sub", "visible.txt"), []byte("ok\n"), fs.ModeFile))
 		// Hidden file
 		assert.NoError(t, os.WriteFile(filepath.Join(tempTheme, ".hidden.txt"), []byte("secret\n"), fs.ModeFile))
@@ -143,4 +147,26 @@ func TestClusterGetTheme(t *testing.T) {
 		assert.Equal(t, http.StatusOK, w.Code)
 		assert.Equal(t, header.ContentTypeZip, w.Header().Get(header.ContentType))
 	})
+	t.Run("UpdateThemeVersion", func(t *testing.T) {
+		app, _, conf := NewApiTest()
+		_ = app // unused
+		conf.Options().NodeRole = cluster.RolePortal
+
+		regy, err := reg.NewClientRegistryWithConfig(conf)
+		assert.NoError(t, err)
+
+		node := &reg.Node{Node: cluster.Node{Name: "pp-node-01", Role: "instance", UUID: rnd.UUIDv7()}}
+		assert.NoError(t, regy.Put(node))
+
+		client := entity.FindClientByUID(node.ClientID)
+		sess := entity.NewSession(-1, -1)
+		sess.SetClient(client)
+		sess.RefID = "sess-test"
+
+		updateNodeThemeVersion(conf, sess, " theme-v1 \n", "127.0.0.1", sess.RefID)
+
+		stored, err := regy.Get(node.UUID)
+		assert.NoError(t, err)
+		assert.Equal(t, "theme-v1", stored.Theme)
+	})
 }
diff --git a/internal/api/swagger.json b/internal/api/swagger.json
index 052232c2c..49b7f34ca 100644
--- a/internal/api/swagger.json
+++ b/internal/api/swagger.json
@@ -349,6 +349,12 @@
                 "AdvertiseUrl": {
                     "type": "string"
                 },
+                "AppName": {
+                    "type": "string"
+                },
+                "AppVersion": {
+                    "type": "string"
+                },
                 "ClientID": {
                     "type": "string"
                 },
@@ -375,6 +381,9 @@
                 "SiteUrl": {
                     "type": "string"
                 },
+                "Theme": {
+                    "type": "string"
+                },
                 "UUID": {
                     "description": "NodeUUID",
                     "type": "string"
@@ -454,6 +463,9 @@
                 "Secrets": {
                     "$ref": "#/definitions/cluster.RegisterSecrets"
                 },
+                "Theme": {
+                    "type": "string"
+                },
                 "UUID": {
                     "description": "ClusterUUID",
                     "type": "string"
@@ -491,6 +503,9 @@
                 "Nodes": {
                     "type": "integer"
                 },
+                "Theme": {
+                    "type": "string"
+                },
                 "Time": {
                     "type": "string"
                 },
@@ -6644,7 +6659,7 @@
                 "operationId": "ClusterNodesRegister",
                 "parameters": [
                     {
-                        "description": "registration payload (NodeName required; optional: NodeRole, Labels, AdvertiseUrl, SiteUrl; to authorize UUID/name changes include ClientID+ClientSecret; rotation: RotateDatabase, RotateSecret)",
+                        "description": "registration payload (NodeName required; optional: NodeRole, Labels, AdvertiseUrl, SiteUrl, AppName, AppVersion, Theme; to authorize UUID/name changes include ClientID+ClientSecret; rotation: RotateDatabase, RotateSecret)",
                         "in": "body",
                         "name": "request",
                         "required": true,
diff --git a/internal/commands/cluster_nodes_rotate.go b/internal/commands/cluster_nodes_rotate.go
index dabbb8f7f..367ced2ef 100644
--- a/internal/commands/cluster_nodes_rotate.go
+++ b/internal/commands/cluster_nodes_rotate.go
@@ -12,6 +12,7 @@ import (
 	"github.com/photoprism/photoprism/internal/config"
 	"github.com/photoprism/photoprism/internal/service/cluster"
 	reg "github.com/photoprism/photoprism/internal/service/cluster/registry"
+	"github.com/photoprism/photoprism/internal/service/cluster/theme"
 	"github.com/photoprism/photoprism/pkg/clean"
 	"github.com/photoprism/photoprism/pkg/txt"
 	"github.com/photoprism/photoprism/pkg/txt/report"
@@ -136,6 +137,11 @@ func clusterNodesRotateAction(ctx *cli.Context) error {
 			NodeName:       name,
 			RotateDatabase: rotateDatabase,
 			RotateSecret:   rotateSecret,
+			AppName:        clean.TypeUnicode(conf.AppName()),
+			AppVersion:     clean.TypeUnicode(conf.Version()),
+		}
+		if themeVersion, err := theme.DetectVersion(conf.ThemePath()); err == nil && themeVersion != "" {
+			payload.Theme = themeVersion
 		}
 		b, _ := json.Marshal(payload)
 
diff --git a/internal/commands/cluster_register.go b/internal/commands/cluster_register.go
index 2d13ec776..7e666ea6c 100644
--- a/internal/commands/cluster_register.go
+++ b/internal/commands/cluster_register.go
@@ -19,6 +19,7 @@ import (
 	"github.com/photoprism/photoprism/internal/config"
 	"github.com/photoprism/photoprism/internal/service/cluster"
 	clusternode "github.com/photoprism/photoprism/internal/service/cluster/node"
+	"github.com/photoprism/photoprism/internal/service/cluster/theme"
 	"github.com/photoprism/photoprism/pkg/clean"
 	"github.com/photoprism/photoprism/pkg/fs"
 	"github.com/photoprism/photoprism/pkg/rnd"
@@ -32,6 +33,8 @@ var (
 	regRoleFlag       = &cli.StringFlag{Name: "role", Usage: "node `ROLE` (instance, service)", Value: "instance"}
 	regIntUrlFlag     = &cli.StringFlag{Name: "advertise-url", Usage: "internal service `URL`"}
 	regSiteUrlFlag    = &cli.StringFlag{Name: "site-url", Usage: "public site `URL` (https://...)"}
+	regAppNameFlag    = &cli.StringFlag{Name: "app-name", Usage: "override application `NAME` reported to the portal"}
+	regAppVersionFlag = &cli.StringFlag{Name: "app-version", Usage: "override application `VERSION` reported to the portal"}
 	regLabelFlag      = &cli.StringSliceFlag{Name: "label", Usage: "`k=v` label (repeatable)"}
 	regRotateDatabase = &cli.BoolFlag{Name: "rotate", Usage: "rotates the node's database password"}
 	regRotateSec      = &cli.BoolFlag{Name: "rotate-secret", Usage: "rotates the node's secret used for JWT"}
@@ -55,6 +58,8 @@ var ClusterRegisterCommand = &cli.Command{
 		regPortalTok,
 		regIntUrlFlag,
 		regSiteUrlFlag,
+		regAppNameFlag,
+		regAppVersionFlag,
 		regLabelFlag,
 		regRotateDatabase,
 		regRotateSec,
@@ -109,6 +114,19 @@ func clusterRegisterAction(ctx *cli.Context) error {
 			site = conf.SiteUrl()
 		}
 
+		overrideAppName := clean.TypeUnicode(ctx.String("app-name"))
+		overrideAppVersion := clean.TypeUnicode(ctx.String("app-version"))
+
+		defaultAppName := clean.TypeUnicode(conf.AppName())
+		defaultAppVersion := clean.TypeUnicode(conf.Version())
+
+		if overrideAppName == "" {
+			overrideAppName = defaultAppName
+		}
+		if overrideAppVersion == "" {
+			overrideAppVersion = defaultAppVersion
+		}
+
 		payload := cluster.RegisterRequest{
 			NodeName:       name,
 			NodeRole:       nodeRole,
@@ -116,6 +134,8 @@ func clusterRegisterAction(ctx *cli.Context) error {
 			AdvertiseUrl:   advertise,
 			RotateDatabase: ctx.Bool("rotate"),
 			RotateSecret:   ctx.Bool("rotate-secret"),
+			AppName:        overrideAppName,
+			AppVersion:     overrideAppVersion,
 		}
 
 		// If auto detection is allowed, rotate database only when the current node lacks configured credentials.
@@ -134,6 +154,9 @@ func clusterRegisterAction(ctx *cli.Context) error {
 		if site != "" {
 			payload.SiteUrl = site
 		}
+		if themeVersion, err := theme.DetectVersion(conf.ThemePath()); err == nil && themeVersion != "" {
+			payload.Theme = themeVersion
+		}
 		b, _ := json.Marshal(payload)
 
 		// In dry-run, we allow empty portalURL (will print derived/empty values).
@@ -155,6 +178,12 @@ func clusterRegisterAction(ctx *cli.Context) error {
 				if payload.SiteUrl != "" {
 					fmt.Printf("Site URL:   %s\n", payload.SiteUrl)
 				}
+				if overrideAppName != "" {
+					fmt.Printf("App Name:   %s\n", overrideAppName)
+				}
+				if overrideAppVersion != "" {
+					fmt.Printf("App Version:%s\n", overrideAppVersion)
+				}
 				// Warn if non-HTTPS on public host; server will enforce too.
 				if warnInsecurePublicURL(advertise) {
 					fmt.Println("Warning: advertise-url is http for a public host; server may reject it (HTTPS required).")
diff --git a/internal/commands/cluster_summary.go b/internal/commands/cluster_summary.go
index e93dee650..c14268770 100644
--- a/internal/commands/cluster_summary.go
+++ b/internal/commands/cluster_summary.go
@@ -10,6 +10,7 @@ import (
 	"github.com/photoprism/photoprism/internal/config"
 	"github.com/photoprism/photoprism/internal/service/cluster"
 	reg "github.com/photoprism/photoprism/internal/service/cluster/registry"
+	"github.com/photoprism/photoprism/internal/service/cluster/theme"
 	"github.com/photoprism/photoprism/pkg/txt/report"
 )
 
@@ -35,11 +36,17 @@ func clusterSummaryAction(ctx *cli.Context) error {
 
 		nodes, _ := r.List()
 
+		themeVersion := ""
+		if v, err := theme.DetectVersion(conf.PortalThemePath()); err == nil {
+			themeVersion = v
+		}
+
 		resp := cluster.SummaryResponse{
 			UUID:        conf.ClusterUUID(),
 			ClusterCIDR: conf.ClusterCIDR(),
 			Nodes:       len(nodes),
 			Database:    cluster.DatabaseInfo{Driver: conf.DatabaseDriverName(), Host: conf.DatabaseHost(), Port: conf.DatabasePort()},
+			Theme:       themeVersion,
 			Time:        time.Now().UTC().Format(time.RFC3339),
 		}
 
@@ -49,8 +56,8 @@ func clusterSummaryAction(ctx *cli.Context) error {
 			return nil
 		}
 
-		cols := []string{"Portal UUID", "Cluster CIDR", "Nodes", "DB Driver", "DB Host", "DB Port", "Time"}
-		rows := [][]string{{resp.UUID, resp.ClusterCIDR, fmt.Sprintf("%d", resp.Nodes), resp.Database.Driver, resp.Database.Host, fmt.Sprintf("%d", resp.Database.Port), resp.Time}}
+		cols := []string{"Portal UUID", "Cluster CIDR", "Nodes", "DB Driver", "DB Host", "DB Port", "Theme", "Time"}
+		rows := [][]string{{resp.UUID, resp.ClusterCIDR, fmt.Sprintf("%d", resp.Nodes), resp.Database.Driver, resp.Database.Host, fmt.Sprintf("%d", resp.Database.Port), resp.Theme, resp.Time}}
 		out, err := report.RenderFormat(rows, cols, report.CliFormat(ctx))
 		fmt.Printf("\n%s\n", out)
 		return err
diff --git a/internal/entity/auth_client.go b/internal/entity/auth_client.go
index d36439cae..dff93eabc 100644
--- a/internal/entity/auth_client.go
+++ b/internal/entity/auth_client.go
@@ -35,6 +35,8 @@ type Client struct {
 	UserUID      string          `gorm:"type:VARBINARY(42);index;default:'';" json:"UserUID" yaml:"UserUID,omitempty"`
 	UserName     string          `gorm:"size:200;index;" json:"UserName" yaml:"UserName,omitempty"`
 	user         *User           `gorm:"-" yaml:"-"`
+	AppName      string          `gorm:"size:64;" json:"AppName" yaml:"AppName,omitempty"`
+	AppVersion   string          `gorm:"size:64;" json:"AppVersion" yaml:"AppVersion,omitempty"`
 	ClientName   string          `gorm:"size:200;" json:"ClientName" yaml:"ClientName,omitempty"`
 	ClientRole   string          `gorm:"size:64;default:'';" json:"ClientRole" yaml:"ClientRole,omitempty"`
 	ClientType   string          `gorm:"type:VARBINARY(16)" json:"ClientType" yaml:"ClientType,omitempty"`
@@ -112,12 +114,24 @@ func FindClientByNodeUUID(nodeUUID string) *Client {
 		return nil
 	}
 	m := &Client{}
-	if err := UnscopedDb().Where("node_uuid = ?", nodeUUID).First(m).Error; err != nil {
+	if err := UnscopedDb().Where("node_uuid = ?", nodeUUID).Order("updated_at DESC").First(m).Error; err != nil {
 		return nil
 	}
 	return m
 }
 
+// FindClientsByNodeUUID returns all client rows matching the given NodeUUID ordered by UpdatedAt descending.
+func FindClientsByNodeUUID(nodeUUID string) []Client {
+	if nodeUUID == "" {
+		return nil
+	}
+	var list []Client
+	if err := UnscopedDb().Where("node_uuid = ?", nodeUUID).Order("updated_at DESC").Find(&list).Error; err != nil {
+		return nil
+	}
+	return list
+}
+
 // GetUID returns the client uid string.
 func (m *Client) GetUID() string {
 	return m.ClientUID
diff --git a/internal/entity/auth_client_data.go b/internal/entity/auth_client_data.go
index a0f40de5a..b30be9414 100644
--- a/internal/entity/auth_client_data.go
+++ b/internal/entity/auth_client_data.go
@@ -16,6 +16,7 @@ type ClientDatabase struct {
 type ClientData struct {
 	Labels          map[string]string `json:"labels,omitempty"`
 	Database        *ClientDatabase   `json:"database,omitempty"`
+	Theme           string            `json:"theme,omitempty"`
 	RotatedAt       string            `json:"rotatedAt,omitempty"`
 	SiteURL         string            `json:"siteUrl,omitempty"`
 	ClusterUUID     string            `json:"clusterUUID,omitempty"`
diff --git a/internal/service/cluster/node/bootstrap.go b/internal/service/cluster/node/bootstrap.go
index f3948fab3..cb6b253a2 100644
--- a/internal/service/cluster/node/bootstrap.go
+++ b/internal/service/cluster/node/bootstrap.go
@@ -21,6 +21,7 @@ import (
 	"github.com/photoprism/photoprism/internal/config"
 	"github.com/photoprism/photoprism/internal/event"
 	"github.com/photoprism/photoprism/internal/service/cluster"
+	"github.com/photoprism/photoprism/internal/service/cluster/theme"
 	"github.com/photoprism/photoprism/pkg/clean"
 	"github.com/photoprism/photoprism/pkg/fs"
 	"github.com/photoprism/photoprism/pkg/rnd"
@@ -140,6 +141,12 @@ func registerWithPortal(c *config.Config, portal *url.URL, token string) error {
 		NodeUUID:     c.NodeUUID(),
 		NodeRole:     c.NodeRole(),
 		AdvertiseUrl: c.AdvertiseUrl(),
+		AppName:      clean.TypeUnicode(c.AppName()),
+		AppVersion:   clean.TypeUnicode(c.Version()),
+	}
+
+	if v, err := theme.DetectVersion(c.ThemePath()); err == nil && v != "" {
+		payload.Theme = v
 	}
 
 	// Auto-derive Advertise/Site URLs from node name and cluster domain when not configured.
diff --git a/internal/service/cluster/node/bootstrap_test.go b/internal/service/cluster/node/bootstrap_test.go
index 511cfba23..8c66ce326 100644
--- a/internal/service/cluster/node/bootstrap_test.go
+++ b/internal/service/cluster/node/bootstrap_test.go
@@ -40,12 +40,16 @@ func TestRegister_PersistSecretAndDB(t *testing.T) {
 	// Fake Portal server.
 	var jwksURL string
 	expectedSite := "https://public.example.test/"
+	var expectedAppName string
+	var expectedAppVersion string
 	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
 		switch r.URL.Path {
 		case "/api/v1/cluster/nodes/register":
 			var req cluster.RegisterRequest
 			assert.NoError(t, json.NewDecoder(r.Body).Decode(&req))
 			assert.Equal(t, expectedSite, req.SiteUrl)
+			assert.Equal(t, expectedAppName, req.AppName)
+			assert.Equal(t, expectedAppVersion, req.AppVersion)
 			// Minimal successful registration with secrets + DSN.
 			w.Header().Set("Content-Type", "application/json")
 			w.WriteHeader(http.StatusCreated)
@@ -84,6 +88,8 @@ func TestRegister_PersistSecretAndDB(t *testing.T) {
 	c.Options().JoinToken = cluster.ExampleJoinToken
 	c.Options().SiteUrl = expectedSite
 	c.Options().AdvertiseUrl = expectedSite
+	expectedAppName = c.AppName()
+	expectedAppVersion = c.Version()
 	// Gate rotate=true: driver mysql and no DSN/fields.
 	c.Options().DatabaseDriver = config.MySQL
 	c.Options().DatabaseDSN = ""
diff --git a/internal/service/cluster/registry/client.go b/internal/service/cluster/registry/client.go
index 98f09489b..bb3a893b3 100644
--- a/internal/service/cluster/registry/client.go
+++ b/internal/service/cluster/registry/client.go
@@ -33,6 +33,8 @@ func toNode(c *entity.Client) *Node {
 		Role:         c.ClientRole,
 		ClientID:     c.ClientUID,
 		AdvertiseUrl: c.ClientURL,
+		AppName:      c.AppName,
+		AppVersion:   c.AppVersion,
 		Labels:       map[string]string{},
 		CreatedAt:    c.CreatedAt.UTC().Format(time.RFC3339),
 		UpdatedAt:    c.UpdatedAt.UTC().Format(time.RFC3339),
@@ -51,6 +53,7 @@ func toNode(c *entity.Client) *Node {
 			dest.RotatedAt = db.RotatedAt
 		}
 		n.RotatedAt = data.RotatedAt
+		n.Theme = data.Theme
 	}
 	return n
 }
@@ -61,9 +64,8 @@ func (r *ClientRegistry) Put(n *Node) error {
 
 	// 1) Try NodeUUID first, if provided.
 	if n.UUID != "" {
-		var existing entity.Client
-		if err := entity.UnscopedDb().Where("node_uuid = ?", n.UUID).First(&existing).Error; err == nil && existing.ClientUID != "" {
-			m = &existing
+		if existing := entity.FindClientByNodeUUID(n.UUID); existing != nil && existing.ClientUID != "" {
+			m = existing
 		}
 	}
 
@@ -114,6 +116,12 @@ func (r *ClientRegistry) Put(n *Node) error {
 	if n.AdvertiseUrl != "" {
 		m.ClientURL = n.AdvertiseUrl
 	}
+	if v := clean.TypeUnicode(n.AppName); v != "" {
+		m.AppName = v
+	}
+	if v := clean.TypeUnicode(n.AppVersion); v != "" {
+		m.AppVersion = v
+	}
 	data := m.GetData()
 	if data.Labels == nil {
 		data.Labels = map[string]string{}
@@ -128,6 +136,9 @@ func (r *ClientRegistry) Put(n *Node) error {
 		m.NodeUUID = n.UUID
 	}
 	data.RotatedAt = n.RotatedAt
+	if theme := clean.TypeUnicode(n.Theme); theme != "" {
+		data.Theme = theme
+	}
 	if db := n.Database; db != nil && (db.Name != "" || db.User != "" || db.RotatedAt != "") {
 		if data.Database == nil {
 			data.Database = &entity.ClientDatabase{}
@@ -157,6 +168,8 @@ func (r *ClientRegistry) Put(n *Node) error {
 	n.Name = m.ClientName
 	n.Role = m.ClientRole
 	n.AdvertiseUrl = m.ClientURL
+	n.AppName = m.AppName
+	n.AppVersion = m.AppVersion
 	n.CreatedAt = m.CreatedAt.UTC().Format(time.RFC3339)
 	n.UpdatedAt = m.UpdatedAt.UTC().Format(time.RFC3339)
 
@@ -173,6 +186,7 @@ func (r *ClientRegistry) Put(n *Node) error {
 			dest.RotatedAt = db.RotatedAt
 		}
 		n.RotatedAt = data.RotatedAt
+		n.Theme = data.Theme
 	}
 	// Set initial secret if provided on create/update.
 	if n.ClientSecret != "" {
@@ -188,11 +202,11 @@ func (r *ClientRegistry) Get(id string) (*Node, error) {
 	if id == "" {
 		return nil, ErrNotFound
 	}
-	var c entity.Client
-	if err := entity.UnscopedDb().Where("node_uuid = ?", id).First(&c).Error; err != nil || c.ClientUID == "" {
+	c := entity.FindClientByNodeUUID(id)
+	if c == nil || c.ClientUID == "" {
 		return nil, ErrNotFound
 	}
-	return toNode(&c), nil
+	return toNode(c), nil
 }
 
 func (r *ClientRegistry) FindByName(name string) (*Node, error) {
@@ -221,20 +235,11 @@ func (r *ClientRegistry) FindByNodeUUID(nodeUUID string) (*Node, error) {
 	if nodeUUID == "" {
 		return nil, ErrNotFound
 	}
-	var list []entity.Client
-	if err := entity.UnscopedDb().Where("node_uuid = ?", nodeUUID).Find(&list).Error; err != nil {
-		return nil, err
-	}
+	list := entity.FindClientsByNodeUUID(nodeUUID)
 	if len(list) == 0 {
 		return nil, ErrNotFound
 	}
-	latest := &list[0]
-	for i := 1; i < len(list); i++ {
-		if list[i].UpdatedAt.After(latest.UpdatedAt) {
-			latest = &list[i]
-		}
-	}
-	return toNode(latest), nil
+	return toNode(&list[0]), nil
 }
 
 // FindByClientID looks up a node by its OAuth client identifier.
@@ -296,10 +301,7 @@ func (r *ClientRegistry) DeleteAllByUUID(uuid string) error {
 	if uuid == "" {
 		return ErrNotFound
 	}
-	var list []entity.Client
-	if err := entity.UnscopedDb().Where("node_uuid = ?", uuid).Find(&list).Error; err != nil {
-		return err
-	}
+	list := entity.FindClientsByNodeUUID(uuid)
 	if len(list) == 0 {
 		return ErrNotFound
 	}
diff --git a/internal/service/cluster/registry/client_test.go b/internal/service/cluster/registry/client_test.go
index e295c6ec3..c5fd15a9d 100644
--- a/internal/service/cluster/registry/client_test.go
+++ b/internal/service/cluster/registry/client_test.go
@@ -25,6 +25,9 @@ func TestClientRegistry_PutFindListRotate(t *testing.T) {
 			UUID:         rnd.UUIDv7(),
 			Name:         "pp-node-a",
 			Role:         "instance",
+			AppName:      "PhotoPrism",
+			AppVersion:   "1.0.0",
+			Theme:        "theme-v1",
 			SiteUrl:      "https://photos.example.com",
 			AdvertiseUrl: "http://pp-node-a:2342",
 			Labels:       map[string]string{"env": "test"},
@@ -48,6 +51,9 @@ func TestClientRegistry_PutFindListRotate(t *testing.T) {
 		assert.True(t, rnd.IsUUID(got.UUID))
 		assert.Equal(t, "pp-node-a", got.Name)
 		assert.Equal(t, "instance", got.Role)
+		assert.Equal(t, "PhotoPrism", got.AppName)
+		assert.Equal(t, "1.0.0", got.AppVersion)
+		assert.Equal(t, "theme-v1", got.Theme)
 		assert.Equal(t, "http://pp-node-a:2342", got.AdvertiseUrl)
 		assert.Equal(t, "https://photos.example.com", got.SiteUrl)
 		if assert.NotNil(t, got.Database) {
@@ -91,12 +97,15 @@ func TestClientRegistry_PutFindListRotate(t *testing.T) {
 	}
 
 	// Update labels and site URL via Put (upsert by id)
-	upd := &Node{Node: cluster.Node{ClientID: got.ClientID, Name: got.Name, Labels: map[string]string{"env": "prod"}, SiteUrl: "https://photos.example.org"}}
+	upd := &Node{Node: cluster.Node{ClientID: got.ClientID, Name: got.Name, Labels: map[string]string{"env": "prod"}, SiteUrl: "https://photos.example.org", AppVersion: "1.1.0"}}
 	assert.NoError(t, r.Put(upd))
 	got2, err := r.FindByName("pp-node-a")
 	assert.NoError(t, err)
 	if assert.NotNil(t, got2) {
 		assert.Equal(t, "prod", got2.Labels["env"])
 		assert.Equal(t, "https://photos.example.org", got2.SiteUrl)
+		assert.Equal(t, "PhotoPrism", got2.AppName)
+		assert.Equal(t, "1.1.0", got2.AppVersion)
+		assert.Equal(t, "theme-v1", got2.Theme)
 	}
 }
diff --git a/internal/service/cluster/registry/registry_uuid_test.go b/internal/service/cluster/registry/registry_uuid_test.go
index a2ee8e94c..ab3d52834 100644
--- a/internal/service/cluster/registry/registry_uuid_test.go
+++ b/internal/service/cluster/registry/registry_uuid_test.go
@@ -88,10 +88,7 @@ func TestClientRegistry_DeleteAllByUUID(t *testing.T) {
 	assert.NoError(t, r.DeleteAllByUUID(uuid))
 
 	// Ensure no rows remain for this UUID
-	var list []entity.Client
-	err := entity.UnscopedDb().Where("node_uuid = ?", uuid).Find(&list).Error
-	assert.NoError(t, err)
-	assert.Equal(t, 0, len(list))
+	assert.Empty(t, entity.FindClientsByNodeUUID(uuid))
 }
 
 // List() should only include clients that represent cluster nodes (i.e., have a NodeUUID).
diff --git a/internal/service/cluster/request.go b/internal/service/cluster/request.go
index 9319c7b39..03b1a2f2a 100644
--- a/internal/service/cluster/request.go
+++ b/internal/service/cluster/request.go
@@ -9,6 +9,9 @@ type RegisterRequest struct {
 	NodeUUID       string            `json:"NodeUUID,omitempty"`
 	NodeRole       string            `json:"NodeRole,omitempty"`
 	Labels         map[string]string `json:"Labels,omitempty"`
+	AppName        string            `json:"AppName,omitempty"`
+	AppVersion     string            `json:"AppVersion,omitempty"`
+	Theme          string            `json:"Theme,omitempty"`
 	AdvertiseUrl   string            `json:"AdvertiseUrl,omitempty"`
 	SiteUrl        string            `json:"SiteUrl,omitempty"`
 	ClientID       string            `json:"ClientID,omitempty"`
diff --git a/internal/service/cluster/response.go b/internal/service/cluster/response.go
index cd9ebb6b6..87ad83cd4 100644
--- a/internal/service/cluster/response.go
+++ b/internal/service/cluster/response.go
@@ -16,6 +16,9 @@ type Node struct {
 	Name         string            `json:"Name"` // NodeName
 	Role         string            `json:"Role"` // NodeRole
 	ClientID     string            `json:"ClientID,omitempty"`
+	AppName      string            `json:"AppName,omitempty"`
+	AppVersion   string            `json:"AppVersion,omitempty"`
+	Theme        string            `json:"Theme,omitempty"`
 	SiteUrl      string            `json:"SiteUrl,omitempty"`
 	AdvertiseUrl string            `json:"AdvertiseUrl,omitempty"`
 	Labels       map[string]string `json:"Labels,omitempty"`
@@ -39,6 +42,7 @@ type SummaryResponse struct {
 	ClusterCIDR string       `json:"ClusterCIDR,omitempty"`
 	Nodes       int          `json:"Nodes"`
 	Database    DatabaseInfo `json:"Database"`
+	Theme       string       `json:"Theme,omitempty"`
 	Time        string       `json:"Time"`
 }
 
@@ -82,6 +86,7 @@ type RegisterResponse struct {
 	JWKSUrl            string           `json:"JWKSUrl,omitempty"`
 	AlreadyRegistered  bool             `json:"AlreadyRegistered"`
 	AlreadyProvisioned bool             `json:"AlreadyProvisioned"`
+	Theme              string           `json:"Theme,omitempty"`
 }
 
 // StatusResponse is a generic status wrapper for simple ok responses.
diff --git a/internal/service/cluster/theme/version.go b/internal/service/cluster/theme/version.go
new file mode 100644
index 000000000..6ef81e089
--- /dev/null
+++ b/internal/service/cluster/theme/version.go
@@ -0,0 +1,32 @@
+package theme
+
+import (
+	"os"
+	"path/filepath"
+	"time"
+
+	"github.com/photoprism/photoprism/pkg/clean"
+	"github.com/photoprism/photoprism/pkg/fs"
+)
+
+// DetectVersion returns the sanitized theme version for the given directory.
+// It prefers a version.txt file when present and falls back to the app.js
+// modification timestamp when the version file is missing or empty.
+func DetectVersion(themePath string) (string, error) {
+	versionFile := filepath.Join(themePath, fs.VersionTxtFile)
+
+	if data, err := os.ReadFile(versionFile); err == nil {
+		if v := clean.TypeUnicode(string(data)); v != "" {
+			return v, nil
+		}
+	}
+
+	appPath := filepath.Join(themePath, fs.AppJsFile)
+	info, err := os.Stat(appPath)
+
+	if err != nil {
+		return "", err
+	}
+
+	return clean.TypeUnicode(info.ModTime().UTC().Format(time.RFC3339)), nil
+}
diff --git a/internal/service/cluster/theme/version_test.go b/internal/service/cluster/theme/version_test.go
new file mode 100644
index 000000000..40d4a4110
--- /dev/null
+++ b/internal/service/cluster/theme/version_test.go
@@ -0,0 +1,41 @@
+package theme
+
+import (
+	"os"
+	"path/filepath"
+	"testing"
+	"time"
+
+	"github.com/stretchr/testify/assert"
+
+	"github.com/photoprism/photoprism/pkg/fs"
+)
+
+func TestDetectVersion(t *testing.T) {
+	t.Run("VersionFilePreferred", func(t *testing.T) {
+		dir := t.TempDir()
+		assert.NoError(t, os.WriteFile(filepath.Join(dir, fs.VersionTxtFile), []byte(" 1.2.3 \n"), fs.ModeFile))
+		assert.NoError(t, os.WriteFile(filepath.Join(dir, fs.AppJsFile), []byte("// app"), fs.ModeFile))
+
+		got, err := DetectVersion(dir)
+		assert.NoError(t, err)
+		assert.Equal(t, "1.2.3", got)
+	})
+	t.Run("FallsBackToAppJS", func(t *testing.T) {
+		dir := t.TempDir()
+		appPath := filepath.Join(dir, fs.AppJsFile)
+		assert.NoError(t, os.WriteFile(appPath, []byte("// app"), fs.ModeFile))
+
+		want := time.Now().UTC().Truncate(time.Second)
+		assert.NoError(t, os.Chtimes(appPath, want, want))
+
+		got, err := DetectVersion(dir)
+		assert.NoError(t, err)
+		assert.Equal(t, want.Format(time.RFC3339), got)
+	})
+	t.Run("MissingAppJS", func(t *testing.T) {
+		dir := t.TempDir()
+		_, err := DetectVersion(dir)
+		assert.Error(t, err)
+	})
+}
diff --git a/pkg/clean/type.go b/pkg/clean/type.go
index 32ecbacb2..3e58548af 100644
--- a/pkg/clean/type.go
+++ b/pkg/clean/type.go
@@ -16,6 +16,50 @@ func Type(s string) string {
 	return clip.Chars(ASCII(s), LengthType)
 }
 
+// TypeUnicode removes unsafe runes, collapses whitespace, and enforces the
+// maximum type length while preserving non-ASCII characters when possible.
+func TypeUnicode(s string) string {
+	if s == "" {
+		return s
+	}
+
+	buf := make([]rune, 0, len([]rune(s)))
+	lastWasSpace := false
+
+	for _, r := range s {
+		if len(buf) >= LengthType {
+			break
+		}
+
+		if unicode.IsSpace(r) {
+			if len(buf) == 0 || lastWasSpace {
+				continue
+			}
+			buf = append(buf, ' ')
+			lastWasSpace = true
+			continue
+		}
+
+		if r <= 31 {
+			continue
+		}
+
+		switch r {
+		case '`', '\\', '|', '"', '\'', '?', '*', '<', '>', '{', '}':
+			continue
+		}
+
+		buf = append(buf, r)
+		lastWasSpace = false
+	}
+
+	for len(buf) > 0 && unicode.IsSpace(buf[len(buf)-1]) {
+		buf = buf[:len(buf)-1]
+	}
+
+	return string(buf)
+}
+
 // TypeUnderscore replaces whitespace, dividers, quotes, brackets, and other special characters with an underscore.
 func TypeUnderscore(s string) string {
 	if s == "" {
diff --git a/pkg/clean/type_test.go b/pkg/clean/type_test.go
index f186b5afe..da8e785bf 100644
--- a/pkg/clean/type_test.go
+++ b/pkg/clean/type_test.go
@@ -53,6 +53,52 @@ func TestType(t *testing.T) {
 	})
 }
 
+func TestTypeUnicode(t *testing.T) {
+	tests := []struct {
+		name       string
+		input      string
+		want       string
+		maxRunes64 bool
+	}{
+		{
+			name:       "Clip",
+			input:      " 幸福 Hanzi are logograms developed for the writing of Chinese! Expressions in an index may not ...!",
+			want:       "幸福 Hanzi are logograms developed for the writing of Chinese! Exp",
+			maxRunes64: true,
+		},
+		{
+			name:  "WhitespaceCollapsed",
+			input: "a b\tc\nd",
+			want:  "a b c d",
+		},
+		{
+			name:  "SpecialCharacters",
+			input: "a-`~/\\:|\"'?*<>{}b",
+			want:  "a-~/:b",
+		},
+		{
+			name:  "NonASCII",
+			input: "äöü",
+			want:  "äöü",
+		},
+		{
+			name:  "Empty",
+			input: "",
+			want:  "",
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			got := TypeUnicode(tt.input)
+			assert.Equal(t, tt.want, got)
+			if tt.maxRunes64 {
+				assert.LessOrEqual(t, len([]rune(got)), LengthType)
+			}
+		})
+	}
+}
+
 func TestTypeLower(t *testing.T) {
 	t.Run("Clip", func(t *testing.T) {
 		result := TypeLower(" 幸福 Hanzi are logograms developed for the writing of Chinese! Expressions in an index may not ...!")
diff --git a/pkg/fs/const.go b/pkg/fs/const.go
index e647df708..266e18f2a 100644
--- a/pkg/fs/const.go
+++ b/pkg/fs/const.go
@@ -45,4 +45,5 @@ const (
 	AssetsJsonFile   = "assets.json"
 	ManifestJsonFile = "manifest.json"
 	SwJsFile         = "sw.js"
+	VersionTxtFile   = "version.txt"
 )