feat: customize login and lobby spaces from the panel

deploy/bootstrap.sh

@@ -3659,16 +3659,12 @@ build_velocity_plugin() {
 # signed with a matching HMAC. Only protocol 47 was measured; the rest of Via's 1.7-1.12 range
 # is its own documented support.
 #
-# Pinned by hash and not by "latest" on purpose. These three jars sit in front of every packet
-# on the proxy, and they are the exact bytes FL-007 measured — a moving tag would quietly make
-# this an unmeasured configuration. Bumping a version means bumping its checksum here.
-#
-# The three versions are a set, not three independent pins. ViaRewind is the component that
-# carries 1.8/1.7 support, and 4.1.2 against ViaVersion/ViaBackwards 5.11.0 fails to load
-# Protocol1_9To1_8 — the single protocol every 1.8 client needs — with "Invalid version: 1"
-# at proxy startup. 4.1.3 is the release that adds 5.11.0 compatibility; a two-arm run of the
-# same proxy image logs that error three times on 4.1.2 and not at all on 4.1.3. Read the
-# ViaRewind release notes before moving ViaVersion or ViaBackwards.
+# Pin the three jars as one compatible set. ViaVersion/ViaBackwards 5.12.0 add
+# the 26.3 protocol used by game-stack.lock; ViaRewind 4.2.0 explicitly supports
+# that pair. The earlier FL-007 join measured 1.8 against Paper 1.21.11, not every
+# client on 26.3. Release notes:
+# https://github.com/ViaVersion/ViaBackwards/releases/tag/5.12.0
+# https://github.com/ViaVersion/ViaRewind/releases/tag/4.2.0
 install_via_plugins() {
   prepare_velocity_layout
   local name version want target url tmp have
@@ -3694,12 +3690,12 @@ install_via_plugins() {
       || die "${name} ${version} checksum mismatch: got ${have}, expected ${want}"
     atomic_install_file "$tmp" "$target" 0644 root root
   done <<'EOF'
-ViaVersion 5.11.0 18d19e90fc9467d68128c076630ae8700449c901402a3ef421837ce006bc8cae
-ViaBackwards 5.11.0 b21983d561e3f92df257683f0133ab6c68ec68175e8acfd82c6231723bf83587
-ViaRewind 4.1.3 2d5970d22b4711c9ab2800932326c7b08acdace25ed7c6bbb8f6ea81054962b4
+ViaVersion 5.12.0 72c40a6a702d67f226fc9a0d8ad82aba1483fdabe2e6159bcdddb2dc070750b0
+ViaBackwards 5.12.0 194e9250224632274d7b3c17e411e031a9223c1863c6f5138d53c721f07ab78d
+ViaRewind 4.2.0 d6634ba57bb82d5161c68dfb393571cdf40511a0beb1b04b8c7ed794a3532c6a
 EOF
   pin_via_block_connections
-  ok "Via staged; clients from 1.8 up can join under modern forwarding"
+  ok "Via staged with 26.3 support; verify client versions against your chosen backend images"
 }
 
 # pin_via_block_connections turns ViaVersion's serverside block-connection tracking off.

deploy/limbo/README.md

@@ -164,3 +164,20 @@ set them by hand:
 The Velocity gate/lobby wiring is printed by `felis setup` and enforces the
 invariant: fresh connections hit `login` first, and only an authenticated release
 from that gate can enter the post-auth lobby or a remembered user backend.
+
+## Customize in the panel
+
+Administrators open **Login & lobby**, select **Login space**, and stop it before
+editing. The form configures the login book title/author/heading/link text/help,
+automatic book opening and the login timeout (30–3600 seconds). These settings
+persist in `/data/felis-experience.json`; an explicit
+`FELIS_LOGIN_TIMEOUT_SECONDS` environment variable takes precedence. The generated
+code, generated login URL and chat guidance are preserved. The authentication
+and transfer destination are not player-facing customization fields.
+
+Use the linked file manager to upload a replacement `/data/spawn.schem`, edit
+Limbo's `server.properties` or add Limbo-compatible plugins, then start the space.
+Paper world ZIPs and Paper plugins do not work in Limbo. The page also exposes
+logs, backups/restore and image/resource settings. New joins are unavailable
+while this front door is stopped; a custom image must retain the login plugin
+and support the proxy's forwarding protocol.

deploy/lobby/README.md

@@ -28,7 +28,7 @@ this at every layer:
 
 ```
 docker build -f deploy/lobby/Dockerfile \
-  --build-arg PAPER_JAR_URL=https://<mirror>/paper-1.21.x-<build>.jar \
+  --build-arg PAPER_JAR_URL=https://<mirror>/paper-26.3-<build>.jar \
   --build-arg PAPER_JAR_SHA256=<sha256 of that jar> \
   -t felis-lobby:demo .
 # Publish into the cluster's registry (on the node; docker treats 127.0.0.1 as
@@ -40,6 +40,30 @@ docker push 127.0.0.1:5000/felis/lobby:demo
 sudo felis setup
 ```
 
+## Customize in the panel
+
+Administrators open **Login & lobby** (`/admin/lobby`). Stop the selected space
+before reading or saving its settings, then start it to apply them. The lobby
+form configures welcome text, menu titles, join behavior, game mode, building
+protection, damage/hunger/void handling, difficulty, time/weather and world rules.
+Settings live in `/data/felis-experience.json`, independently of the image, and
+retain unknown keys when saved. Existing installations without this file use the
+same protected-lobby defaults as before.
+
+The page also exposes the existing file manager (including upload and ZIP
+extraction), console, backups/restore, builder permissions and image/resource
+settings. To replace a map: back up and stop the lobby, upload a world ZIP,
+extract it at the volume root, verify the world directory directly contains
+`level.dat`, and set `level-name` in `server.properties`. Use `setworldspawn x y z`
+in the running lobby console to set its spawn. Plugin JARs go in `plugins/` and
+must match Paper's version; the bundled Felis and LuckPerms JARs are refreshed
+from the image at boot. A custom image must retain the menu/control plugin.
+
+The operator reuses its `init-forwarding` YAML merge for the lobby, preserving
+custom Paper globals while refreshing mandatory authentication settings. The
+image only rewrites that file for standalone runs without a managed forwarding
+initContainer. RCON secrets and the proxy forwarding secret remain managed.
+
 ## Configure (deployer's responsibility)
 
 - Game port must be `25565` (the CRD `GamePort`).
@@ -47,7 +71,7 @@ sudo felis setup
 - The lobby speaks only the `felis:control` plugin-message channel; it holds no
   felis-api token by design (spec §12).
 
-## What the lobby allows
+## Default lobby behavior
 
 felis-paper's `LobbyGuard` keeps the lobby a hub that nobody can hurt, get hurt in,
 or leave a mark on:
@@ -65,6 +89,7 @@ or leave a mark on:
 LuckPerms (`lp user <name> permission set felis.lobby.build true` on the lobby console)
 or op them.
 
-The entrypoint pins `max-players=200` on every boot, over Paper's default of 20: every
+The entrypoint seeds `max-players=200` when absent, over Paper's default of 20;
+subsequent file-editor changes survive restarts: every
 authenticated player passes through here, and a stopped server's players arrive all at
 once.

deploy/lobby/entrypoint.sh

@@ -76,7 +76,10 @@ set_prop online-mode false
 # what one node serves at once, and a flood beyond it is refused at the door instead
 # of running the 1Gi lobby out of memory. What the world itself allows (no damage, no
 # building, the /menu hint) is felis-paper's LobbyGuard.
-set_prop max-players 200
+# Seed capacity once; administrators can tune it in the panel file editor.
+if ! grep -q '^max-players=' "$PROPS"; then
+  set_prop max-players 200
+fi
 
 # RCON is the control plane's write channel (spec §8 写=RCON): the operator probes it
 # for readiness and the player tally, and felis-api runs console/permission commands over
@@ -105,21 +108,21 @@ else
   echo "  injects it from the <server>-rcon Secret when spec.rcon.enabled is true." >&2
 fi
 
-# Rewritten whole, not merged. Paper loads this file and fills every key it does
-# not find with the default, then writes the full tree back — so a proxies-only file is a
-# complete, stable input, and the lobby's other globals are simply always the defaults.
-# That is true of a system server Felis owns end to end; if admins are ever allowed to tune
-# the lobby's globals, this has to become a real YAML merge (yq) instead.
+# The operator's existing init-forwarding step merges the proxy keys on every
+# start, preserving other Paper globals. Standalone runs retain the mandatory
+# rewrite because no initContainer has verified their forwarding settings.
 mkdir -p config
-cat > config/paper-global.yml <<YAML
-# Written by felis-lobby's entrypoint on every boot. Do not hand-edit: the forwarding
-# secret is injected from the felis-forwarding-secret Secret and must match the proxy.
+if [ "${FELIS_MANAGED_FORWARDING:-false}" = true ]; then
+  [ -f config/paper-global.yml ] || { echo "felis-lobby: missing managed forwarding config" >&2; exit 1; }
+else
+  cat > config/paper-global.yml <<YAML
 proxies:
   velocity:
     enabled: true
     online-mode: true
     secret: "${SECRET}"
 YAML
+fi
 
 echo "felis-lobby: server-port=${PORT}, velocity modern forwarding on (UUIDs are Mojang-verified)"
 JAVA_MEMORY_ARG=""

docs/openapi.yaml

@@ -62,6 +62,12 @@ info:
   title: felis-api
   version: 4.1.0
   description: |
+    Staff on the operator console may manage the reserved login/lobby system
+    services through existing management routes, without player ownership rows.
+    Creating and claiming these reserved names remain prohibited. System patches
+    keep public autostart and idle stop disabled. Customization is persisted as
+    felis-experience.json using the existing stopped-server file API.
+
     Control plane for the Felis Minecraft orchestration platform. The same binary
     exposes an internal face (per-caller service tokens, for velocity / backend
     callbacks, never Zero Trust) and an external face (the felis_session cookie, for
@@ -600,9 +606,9 @@ components:
               type: boolean
               description: >-
                 True for a platform-provisioned system service (the login gate, the
-                lobby). Their reserved names are rejected by every per-server route,
-                so the cockpit renders them read-only instead of offering actions
-                that would 400.
+                lobby). Staff can manage them through the existing server routes;
+                players see them read-only. Creating, claiming and deleting these
+                reserved names remain prohibited.
 
     RetireState:
       type: object
@@ -2437,6 +2443,8 @@ paths:
                 properties:
                   name: { type: string }
                   desiredState: { type: string, const: Stopped }
+        '400':
+          $ref: '#/components/responses/BadRequest'
         '401':
           $ref: '#/components/responses/Unauthorized'
         '403':
@@ -2465,6 +2473,8 @@ paths:
                 properties:
                   name: { type: string }
                   claimed: { type: boolean, const: true }
+        '400':
+          $ref: '#/components/responses/BadRequest'
         '401':
           $ref: '#/components/responses/Unauthorized'
         '403':
@@ -3182,6 +3192,8 @@ paths:
           content:
             application/json:
               schema: { $ref: '#/components/schemas/ServerInfo' }
+        '400':
+          $ref: '#/components/responses/BadRequest'
         '401':
           $ref: '#/components/responses/Unauthorized'
         '403':
@@ -4488,7 +4500,7 @@ paths:
         recorded when it was written as it streams; a mismatch cuts the
         download off short of its end. On the way out config/paper-global.yml
         (the cluster's forwarding secret) is left out and server.properties has
-        its rcon.password redacted, so the download carries no Content-Length.
+        its rcon.password and forwarding-secrets redacted, so the download carries no Content-Length.
         A user gets 404 for a backup outside their scope, as their list never
         shows it. One export per user at a time, 2 across the install, 6 per
         user per hour.
@@ -4850,7 +4862,7 @@ paths:
                     type: string
                     pattern: '^[0-9a-f]{64}$'
                     description: >-
-                      SHA-256 of the file as stored (before the rcon.password redaction in
+                      SHA-256 of the file as stored (before secret redaction in
                       server.properties). Send it back as expect_sha256 on the next write.
                   content_sha256:
                     type: string
@@ -5204,7 +5216,7 @@ paths:
         without one, with symbolic links, devices and sockets left out.
         config/paper-global.yml, the cluster's forwarding secret, is refused as
         a file and left out of a folder, and server.properties goes out with
-        its rcon.password redacted; both are matched by the file itself, so a
+        its rcon.password and forwarding-secrets redacted; both are matched by the file itself, so a
         link to either under another name is guarded too. The server cannot
         start until the download has ended. Two file downloads per user at a
         time, 4 across the install, 30 per user per hour, counted apart from

game_entrypoint_test.go

@@ -9,7 +9,7 @@ import (
 )
 
 // The lobby and login gate take their player cap from server.properties, which the
-// entrypoint rewrites on every boot over whatever the volume already holds. These run
+// login gate rewrites on every boot; the lobby seeds it only when absent. These run
 // the shipped entrypoints the way a pod does (image and volume paths pointed into temp
 // dirs, java replaced by a stub that exits) and read the file the server would start on.
 
@@ -91,11 +91,11 @@ func assertProp(t *testing.T, props, key, want string) {
 
 var lobbyImage = []string{"paper.jar", "plugins/felis-paper.jar", "plugins/LuckPerms.jar"}
 
-func TestLobbyEntrypointLiftsThePlayerCap(t *testing.T) {
-	t.Run("over the cap Paper wrote on an earlier boot", func(t *testing.T) {
+func TestLobbyEntrypointSeedsAndPreservesThePlayerCap(t *testing.T) {
+	t.Run("preserves an administrator capacity", func(t *testing.T) {
 		props := runEntrypoint(t, "deploy/lobby/entrypoint.sh", `RUNTIME_DIR="/paper"`, lobbyImage,
 			"#Minecraft server properties\nmax-players=20\nmotd=Kept as it was\n")
-		assertProp(t, props, "max-players", "200")
+		assertProp(t, props, "max-players", "20")
 		assertProp(t, props, "motd", "Kept as it was")
 	})
 	t.Run("on a first boot", func(t *testing.T) {

internal/api/api.go

@@ -26,6 +26,7 @@ import (
 
 	"felis.lolicon.best/internal/apis/felis/v1alpha1"
 	"felis.lolicon.best/internal/fileedit"
+	"felis.lolicon.best/internal/naming"
 )
 
 // API holds the dependencies shared by every handler.
@@ -1197,7 +1198,7 @@ func (l *streamLimiter) release(key string) {
 // reconcile is idempotent and the §18 reaper / §9.3 quota bound steady-state
 // load; the cap exists to refuse an obvious flood, not to hold a hard ceiling.
 func (a *API) withinRunningCap(ctx context.Context, info *ServerInfo) (bool, error) {
-	if a.MaxRunningServers <= 0 {
+	if a.MaxRunningServers <= 0 || naming.IsSystemServer(info.Name) {
 		return true, nil
 	}
 	if info.DesiredState == string(v1alpha1.DesiredRunning) {

internal/api/exports.go

@@ -21,7 +21,6 @@ import (
 	"felis.lolicon.best/internal/apis/felis/v1alpha1"
 	"felis.lolicon.best/internal/fileedit"
 	"felis.lolicon.best/internal/maintenance"
-	"felis.lolicon.best/internal/naming"
 	"felis.lolicon.best/internal/worldexport"
 )
 
@@ -605,11 +604,11 @@ func errExportUnavailable() error {
 func (a *API) exportGate(w http.ResponseWriter, r *http.Request) (string, *ServerRecord, bool) {
 	p := principalFromContext(r.Context())
 	name := r.PathValue("name")
-	if err := naming.ValidateServerName(name); err != nil {
+	if err := validateManagedServerName(r, name); err != nil {
 		writeError(w, r, newError(http.StatusBadRequest, "bad_name", "invalid server name: %v", err))
 		return "", nil, false
 	}
-	rec, err := a.Repo.ServerByName(r.Context(), name)
+	rec, err := a.managedServerRecord(r.Context(), name)
 	if err != nil {
 		a.writeLookupError(w, r, err)
 		return "", nil, false

internal/api/handlers_access.go

@@ -7,8 +7,6 @@ import (
 	"regexp"
 	"strconv"
 	"strings"
-
-	"felis.lolicon.best/internal/naming"
 )
 
 // Access / permissions domain (spec §7). These endpoints let an owner manage
@@ -101,12 +99,12 @@ func (a *API) issueLuckPermsCommand(w http.ResponseWriter, r *http.Request, name
 // the path, not the body) is validated here.
 func (a *API) issueAccessCommand(w http.ResponseWriter, r *http.Request, name, command string) (string, bool) {
 	p := principalFromContext(r.Context())
-	if err := naming.ValidateServerName(name); err != nil {
+	if err := validateManagedServerName(r, name); err != nil {
 		writeError(w, r, newError(http.StatusBadRequest, "bad_name", "invalid server name: %v", err))
 		return "", false
 	}
 
-	rec, err := a.Repo.ServerByName(r.Context(), name)
+	rec, err := a.managedServerRecord(r.Context(), name)
 	if err != nil {
 		a.writeLookupError(w, r, err)
 		return "", false

internal/api/handlers_backups.go

@@ -183,7 +183,7 @@ func restoreMayRead(jobs []AsyncJob, id string) bool {
 func (a *API) handleRestoreBackup(w http.ResponseWriter, r *http.Request) {
 	p := principalFromContext(r.Context())
 	name := r.PathValue("name")
-	if err := naming.ValidateServerName(name); err != nil {
+	if err := validateManagedServerName(r, name); err != nil {
 		writeError(w, r, newError(http.StatusBadRequest, "bad_name", "invalid server name: %v", err))
 		return
 	}
@@ -191,7 +191,7 @@ func (a *API) handleRestoreBackup(w http.ResponseWriter, r *http.Request) {
 	// Ownership: owner or admin, mirroring handleStop. An unknown server is 404; an
 	// unowned (released) server fails the owner check for everyone but admin, which
 	// is exactly the "must re-claim first" rule.
-	rec, err := a.Repo.ServerByName(r.Context(), name)
+	rec, err := a.managedServerRecord(r.Context(), name)
 	if err != nil {
 		a.writeLookupError(w, r, err)
 		return
@@ -367,12 +367,12 @@ func (a *API) handleRestoreBackup(w http.ResponseWriter, r *http.Request) {
 func (a *API) handleBackupNow(w http.ResponseWriter, r *http.Request) {
 	p := principalFromContext(r.Context())
 	name := r.PathValue("name")
-	if err := naming.ValidateServerName(name); err != nil {
+	if err := validateManagedServerName(r, name); err != nil {
 		writeError(w, r, newError(http.StatusBadRequest, "bad_name", "invalid server name: %v", err))
 		return
 	}
 
-	rec, err := a.Repo.ServerByName(r.Context(), name)
+	rec, err := a.managedServerRecord(r.Context(), name)
 	if err != nil {
 		a.writeLookupError(w, r, err)
 		return

internal/api/handlers_console.go

@@ -3,8 +3,6 @@ package api
 import (
 	"errors"
 	"net/http"
-
-	"felis.lolicon.best/internal/naming"
 )
 
 // maxConsoleCommandLen caps the command body well under RCON's single-packet
@@ -39,7 +37,7 @@ type commandRequest struct {
 func (a *API) handleCommand(w http.ResponseWriter, r *http.Request) {
 	p := principalFromContext(r.Context())
 	name := r.PathValue("name")
-	if err := naming.ValidateServerName(name); err != nil {
+	if err := validateManagedServerName(r, name); err != nil {
 		writeError(w, r, newError(http.StatusBadRequest, "bad_name", "invalid server name: %v", err))
 		return
 	}
@@ -58,7 +56,7 @@ func (a *API) handleCommand(w http.ResponseWriter, r *http.Request) {
 	}
 
 	// Ownership: owner or admin, mirroring handleStop. An unknown server is 404.
-	rec, err := a.Repo.ServerByName(r.Context(), name)
+	rec, err := a.managedServerRecord(r.Context(), name)
 	if err != nil {
 		a.writeLookupError(w, r, err)
 		return

internal/api/handlers_fileops.go

@@ -11,7 +11,6 @@ import (
 
 	"felis.lolicon.best/internal/fileedit"
 	"felis.lolicon.best/internal/maintenance"
-	"felis.lolicon.best/internal/naming"
 )
 
 // A file too big for the one-request upload (handleUploadFile) arrives as an
@@ -430,11 +429,11 @@ func (a *API) requireFileStage(w http.ResponseWriter, r *http.Request) (string,
 // staff. It returns the server name.
 func (a *API) authorizeServerFiles(w http.ResponseWriter, r *http.Request) (string, bool) {
 	name := r.PathValue("name")
-	if err := naming.ValidateServerName(name); err != nil {
+	if err := validateManagedServerName(r, name); err != nil {
 		writeError(w, r, newError(http.StatusBadRequest, "bad_name", "invalid server name: %v", err))
 		return "", false
 	}
-	rec, err := a.Repo.ServerByName(r.Context(), name)
+	rec, err := a.managedServerRecord(r.Context(), name)
 	if err != nil {
 		a.writeLookupError(w, r, err)
 		return "", false

internal/api/handlers_logstream.go

@@ -4,8 +4,6 @@ import (
 	"context"
 	"errors"
 	"net/http"
-
-	"felis.lolicon.best/internal/naming"
 )
 
 // handleServerConsole streams the caller's server console as Server-Sent Events
@@ -39,13 +37,13 @@ import (
 func (a *API) handleServerConsole(w http.ResponseWriter, r *http.Request) {
 	p := principalFromContext(r.Context())
 	name := r.PathValue("name")
-	if err := naming.ValidateServerName(name); err != nil {
+	if err := validateManagedServerName(r, name); err != nil {
 		writeError(w, r, newError(http.StatusBadRequest, "bad_name", "invalid server name: %v", err))
 		return
 	}
 
 	// Ownership: owner or admin, mirroring handleCommand. An unknown server is 404.
-	rec, err := a.Repo.ServerByName(r.Context(), name)
+	rec, err := a.managedServerRecord(r.Context(), name)
 	if err != nil {
 		a.writeLookupError(w, r, err)
 		return
@@ -105,7 +103,7 @@ func (a *API) handleServerConsole(w http.ResponseWriter, r *http.Request) {
 
 	a.audit(r, "console.attach", name)
 	relayLogStream(w, r, src, a.streamRecheck(r, func(ctx context.Context, p *Principal) error {
-		rec, err := a.Repo.ServerByName(ctx, name)
+		rec, err := a.managedServerRecord(ctx, name)
 		switch {
 		case errors.Is(err, ErrNotFound):
 			return errForbidden // the server is gone, and the grant with it

internal/api/handlers_user.go

@@ -20,7 +20,7 @@ import (
 func (a *API) handleWake(w http.ResponseWriter, r *http.Request) {
 	p := principalFromContext(r.Context())
 	name := r.PathValue("name")
-	if err := naming.ValidateServerName(name); err != nil {
+	if err := validateManagedServerName(r, name); err != nil {
 		writeError(w, r, newError(http.StatusBadRequest, "bad_name", "invalid server name: %v", err))
 		return
 	}
@@ -97,12 +97,12 @@ func (a *API) handleWake(w http.ResponseWriter, r *http.Request) {
 func (a *API) handleStop(w http.ResponseWriter, r *http.Request) {
 	p := principalFromContext(r.Context())
 	name := r.PathValue("name")
-	if err := naming.ValidateServerName(name); err != nil {
+	if err := validateManagedServerName(r, name); err != nil {
 		writeError(w, r, newError(http.StatusBadRequest, "bad_name", "invalid server name: %v", err))
 		return
 	}
 
-	rec, err := a.Repo.ServerByName(r.Context(), name)
+	rec, err := a.managedServerRecord(r.Context(), name)
 	if err != nil {
 		a.writeLookupError(w, r, err)
 		return
@@ -217,7 +217,7 @@ func (a *API) claimResources(ctx context.Context, name string) (ResourceSpec, er
 // handleStatus returns the CRD status view (spec §7 GET /servers/{name}/status).
 func (a *API) handleStatus(w http.ResponseWriter, r *http.Request) {
 	name := r.PathValue("name")
-	if err := naming.ValidateServerName(name); err != nil {
+	if err := validateManagedServerName(r, name); err != nil {
 		writeError(w, r, newError(http.StatusBadRequest, "bad_name", "invalid server name: %v", err))
 		return
 	}
@@ -899,7 +899,7 @@ const (
 // the adminOnly wrapper in routing — every caller here is already an admin.
 func (a *API) handlePatchServer(w http.ResponseWriter, r *http.Request) {
 	name := r.PathValue("name")
-	if err := naming.ValidateServerName(name); err != nil {
+	if err := validateManagedServerName(r, name); err != nil {
 		writeError(w, r, newError(http.StatusBadRequest, "bad_name", "invalid server name: %v", err))
 		return
 	}
@@ -910,6 +910,13 @@ func (a *API) handlePatchServer(w http.ResponseWriter, r *http.Request) {
 		return
 	}
 
+	if naming.IsSystemServer(name) &&
+		((body.AutostartPolicy != nil && *body.AutostartPolicy != string(v1alpha1.AutostartPublic)) ||
+			(body.IdleStopSeconds != nil && *body.IdleStopSeconds != 0)) {
+		writeError(w, r, newError(http.StatusBadRequest, "bad_request", "system services must remain public and exempt from idle stop"))
+		return
+	}
+
 	// An empty patch is a client mistake, not a no-op success.
 	if body.DisplayName == nil && body.AutostartPolicy == nil && body.Image == nil &&
 		body.Memory == nil && body.Resources == nil && body.Storage == nil && body.IdleStopSeconds == nil {
@@ -1073,7 +1080,7 @@ func (a *API) handlePatchServer(w http.ResponseWriter, r *http.Request) {
 	// fits (ResizeServer). Only growth is held to the caps: a change that grows
 	// neither CPU nor memory cannot push the owner past one, and it is how an admin
 	// brings a server back under a cap lowered below what the owner already uses.
-	if resUpdated {
+	if resUpdated && !naming.IsSystemServer(name) {
 		newCPU := quantityToMilli(newResources.Limits[corev1.ResourceCPU])
 		newMemMB := quantityToMB(newResources.Limits[corev1.ResourceMemory])
 

internal/api/jobstatus.go

@@ -4,8 +4,6 @@ import (
 	"context"
 	"net/http"
 	"time"
-
-	"felis.lolicon.best/internal/naming"
 )
 
 // AsyncJob is the observable outcome of one asynchronous world operation. The API
@@ -45,11 +43,11 @@ type JobStatusReader interface {
 func (a *API) handleServerJobs(w http.ResponseWriter, r *http.Request) {
 	p := principalFromContext(r.Context())
 	name := r.PathValue("name")
-	if err := naming.ValidateServerName(name); err != nil {
+	if err := validateManagedServerName(r, name); err != nil {
 		writeError(w, r, newError(http.StatusBadRequest, "bad_name", "invalid server name: %v", err))
 		return
 	}
-	rec, err := a.Repo.ServerByName(r.Context(), name)
+	rec, err := a.managedServerRecord(r.Context(), name)
 	if err != nil {
 		a.writeLookupError(w, r, err)
 		return

internal/api/systemservers.go

@@ -0,0 +1,28 @@
+package api
+
+import (
+	"context"
+	"net/http"
+
+	"felis.lolicon.best/internal/naming"
+)
+
+// System services have no player owner or business-layer row. Staff manage their
+// existing cluster objects; creation and claiming keep the reserved-name gate.
+func validateManagedServerName(r *http.Request, name string) error {
+	if p := principalFromContext(r.Context()); naming.IsSystemServer(name) && p != nil && p.IsAdmin() {
+		return naming.ValidateSystemServerName(name)
+	}
+	return naming.ValidateServerName(name)
+}
+
+func (a *API) managedServerRecord(ctx context.Context, name string) (*ServerRecord, error) {
+	if !naming.IsSystemServer(name) {
+		return a.Repo.ServerByName(ctx, name)
+	}
+	info, err := a.Cluster.GetServer(ctx, name)
+	if err != nil {
+		return nil, err
+	}
+	return &ServerRecord{Name: name, Subdomain: info.Subdomain}, nil
+}

internal/api/systemservers_test.go

@@ -0,0 +1,123 @@
+package api
+
+import (
+	"context"
+	"fmt"
+	"io"
+	"net/http"
+	"net/http/httptest"
+	"strings"
+	"testing"
+	"time"
+
+	corev1 "k8s.io/api/core/v1"
+	"k8s.io/apimachinery/pkg/api/resource"
+)
+
+func TestSystemServerManagement(t *testing.T) {
+	for _, name := range []string{"login", "lobby"} {
+		for _, principal := range []*Principal{
+			{UserID: "staff", Role: "admin", ViaAdminAccess: true},
+			{UserID: "staff", Role: "admin"},
+			{UserID: "player", Role: "user"},
+		} {
+			t.Run(fmt.Sprintf("%s/%s/operator=%t", name, principal.Role, principal.ViaAdminAccess), func(t *testing.T) {
+				api, repo, cl, files := mkFiles(t)
+				api.External = staticExternal{p: principal}
+				cl.byName[name] = &ServerInfo{Name: name, Subdomain: name, Phase: "Stopped", DesiredState: "Stopped", ReaperExempt: true}
+				// These services are cluster-owned; there deliberately is no database row.
+				for _, route := range []struct {
+					method, suffix, body string
+					success              int
+				}{
+					{"GET", "/status", "", 200},
+					{"GET", "/files", "", 200},
+					{"GET", "/file?path=felis-experience.json", "", 200},
+					{"PUT", "/file?path=felis-experience.json", `{"content":"aGk=","content_sha256":"` + hiSum + `"}`, 200},
+					{"PATCH", "", `{"displayName":"Custom Space"}`, 200},
+					{"POST", "/stop", "", 202},
+				} {
+					before := files.calls
+					result := do(api.ExternalHandler(), route.method, "/api/v1/servers/"+name+route.suffix, route.body, jsonHeader)
+					if principal.IsAdmin() {
+						if result.Code != route.success {
+							t.Fatalf("%s %s: %d %s", route.method, route.suffix, result.Code, result.Body.String())
+						}
+					} else {
+						if result.Code < 400 || files.calls != before {
+							t.Fatalf("player management admitted: %d %s", result.Code, result.Body.String())
+						}
+					}
+				}
+				result := do(api.ExternalHandler(), "POST", "/api/v1/servers/"+name+"/claim", "", nil)
+				if result.Code != http.StatusBadRequest {
+					t.Fatalf("system service claim: %d", result.Code)
+				}
+				if _, exists := repo.byName[name]; exists {
+					t.Fatal("management created a claimable business row")
+				}
+			})
+		}
+	}
+}
+
+func TestSystemServerResourcesAndInvariants(t *testing.T) {
+	api, repo, cl, _ := newPatchAPI()
+	cl.byName["lobby"] = &ServerInfo{Name: "lobby", ReaperExempt: true, Resources: corev1.ResourceRequirements{
+		Limits:   corev1.ResourceList{corev1.ResourceMemory: resource.MustParse("1Gi")},
+		Requests: corev1.ResourceList{corev1.ResourceMemory: resource.MustParse("1Gi")},
+	}}
+	result := do(api.ExternalHandler(), "PATCH", "/api/v1/servers/lobby", `{"memory":"2Gi"}`, jsonHeader)
+	if result.Code != http.StatusOK || cl.patched["lobby"].JavaMemory == nil {
+		t.Fatalf("resource patch: %d %s", result.Code, result.Body.String())
+	}
+	if _, exists := repo.byName["lobby"]; exists {
+		t.Fatal("system resources added an ownership row")
+	}
+	for _, body := range []string{`{"autostartPolicy":"ownerOnly"}`, `{"idleStopSeconds":600}`} {
+		result := do(api.ExternalHandler(), "PATCH", "/api/v1/servers/lobby", body, jsonHeader)
+		if result.Code != http.StatusBadRequest {
+			t.Fatalf("system invariant changed: %d %s", result.Code, result.Body.String())
+		}
+	}
+	delete(cl.byName, "lobby")
+	result = do(api.ExternalHandler(), "POST", "/api/v1/servers/lobby/stop", "", nil)
+	if result.Code != http.StatusNotFound {
+		t.Fatalf("missing cluster service: %d %s", result.Code, result.Body.String())
+	}
+}
+
+func TestSystemLobbyBuilderAccess(t *testing.T) {
+	api, repo, cl, console := mkAccess(t)
+	api.External = staticExternal{p: &Principal{UserID: "staff", Role: "admin", ViaAdminAccess: true}}
+	cl.byName["lobby"] = &ServerInfo{Name: "lobby", Phase: "Running", Ready: true}
+	result := do(api.ExternalHandler(), "POST", "/api/v1/servers/lobby/access/permission",
+		`{"action":"set","player":"Steve","node":"felis.lobby.build","value":true}`, jsonHeader)
+	if result.Code != http.StatusOK || console.gotCommand != "lp user Steve permission set felis.lobby.build true" {
+		t.Fatalf("builder grant: %d %s; command %q", result.Code, result.Body.String(), console.gotCommand)
+	}
+	if _, exists := repo.byName["lobby"]; exists {
+		t.Fatal("builder access created an ownership row")
+	}
+}
+
+func TestSystemConsoleStreamRechecksWithoutOwnershipRow(t *testing.T) {
+	shrinkStreamTimers(t, 10*time.Millisecond, 80*time.Millisecond)
+	a, _, cl, _ := mkAccess(t)
+	a.External = staticExternal{p: &Principal{UserID: "staff", Role: "admin", ViaAdminAccess: true}}
+	cl.byName["lobby"] = &ServerInfo{Name: "lobby", Phase: "Running", Ready: true}
+	a.Logs = &fakeLogStreamer{srcFromCtx: func(ctx context.Context) io.ReadCloser {
+		return &ctxBlockingReadCloser{ctx: ctx, first: []byte("boot\n"), firstRead: make(chan struct{}), closed: make(chan struct{})}
+	}}
+	begun := time.Now()
+	done := make(chan *httptest.ResponseRecorder, 1)
+	go func() { done <- do(a.ExternalHandler(), "GET", "/api/v1/servers/lobby/console", "", nil) }()
+	select {
+	case result := <-done:
+		if result.Code != http.StatusOK || strings.Contains(result.Body.String(), "event: revoked") || time.Since(begun) < 80*time.Millisecond {
+			t.Fatalf("system logs ended before their lifetime: %d %s", result.Code, result.Body.String())
+		}
+	case <-time.After(2 * time.Second):
+		t.Fatal("system log stream outlived its lifetime")
+	}
+}

internal/fileedit/exec.go

@@ -456,7 +456,7 @@ const (
 	redactedValue = "<redacted by felis>"
 )
 
-// redactSecretProps blanks the RCON password when server.properties is read.
+// redactSecretProps hides RCON and Limbo forwarding secrets when server.properties is read.
 //
 // Unlike secretConfigPath this is a value redaction rather than a whole-file
 // denial, because the file is not platform material that merely happens to sit in
@@ -468,6 +468,9 @@ const (
 // regardless of blast radius, and because the console already gives an owner every
 // capability the password would.
 //
+// Limbo stores its cluster forwarding key in this file too; that value is
+// withheld by the same redaction and refreshed by the Limbo entrypoint.
+//
 // The write path is left alone on purpose, mirroring the reasoning at
 // secretConfigPath: felis-lobby's entrypoint rewrites all three rcon keys from the
 // injected Secret on every boot, so saving the placeholder back cannot lock the
@@ -481,8 +484,10 @@ func redactSecretProps(name string, content []byte) []byte {
 	for i, line := range lines {
 		// TrimSpace before matching: a properties key may be indented, and the
 		// trailing \r of a CRLF file would otherwise ride along into the value.
-		if bytes.HasPrefix(bytes.TrimSpace(line), []byte(rconPasswordKey+"=")) {
-			lines[i] = []byte(rconPasswordKey + "=" + redactedValue)
+		for _, key := range []string{rconPasswordKey, "forwarding-secrets"} {
+			if bytes.HasPrefix(bytes.TrimSpace(line), []byte(key+"=")) {
+				lines[i] = []byte(key + "=" + redactedValue)
+			}
 		}
 	}
 	return bytes.Join(lines, []byte("\n"))

internal/fileedit/exec_test.go

@@ -678,3 +678,23 @@ func assertNoTemporaries(t *testing.T, dir string) {
 		}
 	}
 }
+
+func TestReadRedactsLimboForwardingSecret(t *testing.T) {
+	root := t.TempDir()
+	props := "spawn-x=8\nforwarding-secrets=shared-key\nvelocity-modern=true\n"
+	if err := os.WriteFile(filepath.Join(root, "server.properties"), []byte(props), 0o644); err != nil {
+		t.Fatal(err)
+	}
+	if err := os.Link(filepath.Join(root, "server.properties"), filepath.Join(root, "copy.properties")); err != nil {
+		t.Fatal(err)
+	}
+	for _, path := range []string{"server.properties", "copy.properties"} {
+		res, err := run(root, OpRead, path, nil, "")
+		if err != nil || res.Code != "" {
+			t.Fatalf("read: %+v %v", res, err)
+		}
+		if strings.Contains(string(res.Content), "shared-key") || !strings.Contains(string(res.Content), "spawn-x=8") {
+			t.Fatalf("unsafe redaction: %s", res.Content)
+		}
+	}
+}

internal/fileedit/guard.go

@@ -9,7 +9,7 @@ import (
 // What leaves a world mount — a read, a download, a world export, a backup
 // export — passes the same two guards: the forwarding-secret file
 // (secretConfigPath) is withheld, and server.properties has its RCON password
-// redacted (propsPath).
+// redacted (propsPath), along with Limbo's forwarding-secrets.
 //
 // On a live mount both are matched by the file itself (os.SameFile), not by the
 // name it was reached under. A plugin runs arbitrary code as the game uid and can
@@ -51,7 +51,7 @@ func ArchiveRule(name string) (withhold, redact bool) {
 	return name == secretConfigPath, name == propsPath
 }
 
-// RedactProps replaces the RCON password in server.properties content with
+// RedactProps replaces RCON and Limbo forwarding secrets in server.properties with
 // redactedValue (see redactSecretProps for why a placeholder and not a blank).
 func RedactProps(content []byte) []byte {
 	return redactSecretProps(propsPath, content)

internal/naming/naming.go

@@ -48,11 +48,8 @@ const (
 	SystemLobbyServer = "lobby"
 )
 
-// IsSystemServer reports whether name is one of the platform-provisioned system
-// services above. They carry reserved names on purpose, and the API's per-server
-// routes reject those names outright (ValidateServerName) — so a caller that only
-// DISPLAYS fleet rows uses this to mark them as not user-manageable instead of
-// offering actions (claim/wake/stop/console) that would answer 400.
+// IsSystemServer identifies platform services whose reserved names may be managed
+// by staff, but never created or claimed through player-facing routes.
 func IsSystemServer(name string) bool {
 	return name == SystemLoginServer || name == SystemLobbyServer
 }

internal/operator/builders.go

@@ -269,15 +269,18 @@ func buildStatefulSet(server *v1alpha1.MinecraftServer, replicas int32, felisIma
 	// Every server first hands its world volume to the game uid (prepareDataInitContainer),
 	// since the pod runs as that uid and a world an older root-run release wrote would
 	// otherwise be read-only to it. An arbitrary user Paper image then gets the forwarding
-	// config written for it (it does not consume FELIS_FORWARDING_SECRET itself); system
-	// servers (login/lobby) are Felis-built and handle forwarding in their own
-	// entrypoints. Last, every server waits for its egress fence (egressGateInitContainer).
+	// config written for it (it does not consume FELIS_FORWARDING_SECRET itself).
+	// The lobby uses the same merge so custom settings survive; the login Limbo
+	// handles its own properties format. Every server then waits for its egress fence.
 	// Without a felis image name there is nothing to run any step with.
 	var initContainers []corev1.Container
 	if felisImage != "" {
 		initContainers = append(initContainers, prepareDataInitContainer(felisImage))
-		if server.Labels[v1alpha1.LabelSystemRole] == "" {
+		if server.Labels[v1alpha1.LabelSystemRole] != naming.SystemLoginServer {
 			initContainers = append(initContainers, forwardingInitContainer(felisImage))
+			if server.Labels[v1alpha1.LabelSystemRole] == naming.SystemLobbyServer {
+				container.Env = append(container.Env, corev1.EnvVar{Name: "FELIS_MANAGED_FORWARDING", Value: "true"})
+			}
 		}
 		gate := egressGateInitContainer(felisImage)
 		if server.Spec.NodeName != "" || (len(gateProbe) > 0 && gateProbe[0] != "") {
@@ -447,8 +450,8 @@ func forwardingSecretEnvVar() corev1.EnvVar {
 // at all: no capability, a read-only root filesystem, and the files it writes are
 // owned by the very uid that rewrites them on boot.
 //
-// Only user servers get it: the Felis-built system images (login limbo, lobby) already
-// consume the secret in their own entrypoints, and the login limbo is not Paper at all.
+// User Paper servers and the lobby share this merge. The login Limbo handles
+// its own properties format in its entrypoint.
 func forwardingInitContainer(felisImage string) corev1.Container {
 	return corev1.Container{
 		Name:    "init-forwarding",

internal/operator/builders_internal_test.go

@@ -89,7 +89,7 @@ func TestReadinessProbeHTTPCustomPath(t *testing.T) {
 
 // A user server (no system-role label) gets the forwarding-config initContainer after
 // prepare-data, running the felis image and mounting the world volume. A system
-// server gets no forwarding step, and a build with no felis image name gets no step.
+// login gate handles its own properties; a build with no felis image name gets no step.
 func TestBuildStatefulSetForwardingInitContainer(t *testing.T) {
 	user := &v1alpha1.MinecraftServer{}
 	user.Spec.Storage.Size = "1Gi"
@@ -143,14 +143,23 @@ func TestBuildStatefulSetForwardingInitContainer(t *testing.T) {
 		t.Error("no felis image must yield no initContainer")
 	}
 
-	// System server handles forwarding in its own entrypoint, but its world still
-	// needs handing to the game uid and its image waits for the fence all the same.
+	// The lobby shares the forwarding merge, preserving its custom Paper globals.
 	sys := &v1alpha1.MinecraftServer{}
 	sys.Spec.Storage.Size = "1Gi"
 	sys.Labels = map[string]string{v1alpha1.LabelSystemRole: "lobby"}
 	sysSts, _ := buildStatefulSet(sys, 1, "felis:demo")
-	if got := sysSts.Spec.Template.Spec.InitContainers; len(got) != 2 || got[0].Name != "prepare-data" || got[1].Name != "egress-gate" {
-		t.Errorf("system server must get [prepare-data egress-gate], got %+v", got)
+	if got := sysSts.Spec.Template.Spec.InitContainers; len(got) != 3 || got[0].Name != "prepare-data" || got[1].Name != "init-forwarding" || got[2].Name != "egress-gate" {
+		t.Errorf("lobby must get [prepare-data init-forwarding egress-gate], got %+v", got)
+	}
+
+	managed := false
+	for _, env := range sysSts.Spec.Template.Spec.Containers[0].Env {
+		if env.Name == "FELIS_MANAGED_FORWARDING" && env.Value == "true" {
+			managed = true
+		}
+	}
+	if !managed {
+		t.Fatal("lobby entrypoint would overwrite the merged forwarding config")
 	}
 }
 

panel/dev/mockApi.ts

@@ -286,6 +286,10 @@ function initialState(): MockState {
       server("claim-me", "Claimable Node", "Stopped", null, {
         playersMax: 10,
       }),
+      server("login", "Login space", "Stopped", null, {
+        autostartPolicy: "public", idleStopSeconds: 0, reaperExempt: true,
+        image: "registry.felis.svc:5000/felis/limbo:demo", memory: "512Mi", storageSize: "1Gi",
+      }),
       ...generatedServers(),
     ],
     access: {
@@ -764,7 +768,8 @@ function fleetView(state: MockState, accountInfo: MockAccount): FleetServer[] {
       playersOnline: s.ready ? s.playersOnline : 0,
       owner: owner ? state.accounts[owner].email : "",
       owned: owner === accountInfo.id,
-      claimable: owner === null && !s.retiring,
+      claimable: owner === null && !s.retiring && !s.reaperExempt,
+      system: s.reaperExempt,
     };
   });
 }
@@ -2241,6 +2246,10 @@ async function handleServerRoute(ctx: SessionContext): Promise<boolean> {
     sendError(ctx.res, 404, "not_found", "server not found");
     return true;
   }
+  if (serverInfo.reaperExempt && !isAdmin(ctx.account.role)) {
+    sendError(ctx.res, 400, "bad_name", "system service is reserved for staff");
+    return true;
+  }
   if (!canSee(ctx.account, serverInfo)) {
     sendError(ctx.res, 403, "forbidden", "server is not visible to this account");
     return true;
@@ -2474,7 +2483,7 @@ async function handleFilesMock(ctx: SessionContext, serverInfo: MockServer): Pro
       if (!node) return fail(404, "not_found", `${p} does not exist`);
       if (node.is_dir) return fail(400, "bad_path", `${p} is a directory, not a file`);
       if (node.data.length > MOCK_MAX_READ) return fail(413, "too_large", `${p} is larger than the editor reads`);
-      sendJSON(ctx.res, 200, { path: p, content: node.data.toString("base64"), sha256: mockSha(node.data) });
+      sendJSON(ctx.res, 200, { path: p, content: node.data.toString("base64"), sha256: mockSha(node.data), content_sha256: mockSha(node.data) });
       return true;
     }
     case "PUT file": {

panel/e2e/a11y.spec.ts

@@ -30,6 +30,7 @@ for (const [account, path] of [
   ["linked", "/account"],
   ["owner", "/"],
   ["owner", "/servers"],
+  ["owner", "/admin/lobby?space=login"],
   ["owner", "/admin/images"],
   ["owner", "/admin/builds"],
   ["owner", "/admin/submissions"],

panel/e2e/mobile.spec.ts

@@ -50,3 +50,14 @@ test("the LuckPerms player list leaves the rest of the page on the first screen"
   await page.getByRole("button", { name: "Herobrine", exact: true }).click();
   await expect(page.getByRole("textbox", { name: t("servers:luckperms_player_lookup") })).toHaveValue("Herobrine");
 });
+
+test("login customization fits a phone and retains a saved title", async ({ page, signIn }) => {
+  await signIn("owner");
+  await page.goto("/admin/lobby?space=login");
+  await page.getByLabel(t("lobby:bookTitle")).fill("Our Network");
+  await expectFitsScreen(page);
+  await page.getByRole("button", { name: t("lobby:save"), exact: true }).click();
+  await expect(page.getByText(t("lobby:saved"), { exact: true })).toBeVisible();
+  await page.reload();
+  await expect(page.getByLabel(t("lobby:bookTitle"))).toHaveValue("Our Network");
+});

panel/e2e/smoke.spec.ts

@@ -98,7 +98,7 @@ test("an unlinked Owner can manage the panel, then preview and confirm a game ro
 // Admin pages are chunks of their own, so a player never downloads them: every
 // page module is fetched by its name (/src/pages/admin/UsersPage.tsx under the
 // dev server, /assets/UsersPage-<hash>.js in a build).
-const ADMIN_PAGE = /\/(UsersPage|UserDetailPage|ImageAdmin|ImageBuildPage|SubmissionsPage|UpdatesPage)[.-]/;
+const ADMIN_PAGE = /\/(UsersPage|UserDetailPage|LobbyPage|ImageAdmin|ImageBuildPage|SubmissionsPage|UpdatesPage)[.-]/;
 const ACCOUNT_PAGE = /\/Account[.-]/;
 
 test("a player's pages load on demand and never pull in the admin pages", async ({ page, signIn }) => {
@@ -130,3 +130,22 @@ test("on a wide screen the LuckPerms player list runs down its column", async ({
   await page.setViewportSize({ width: 1280, height: 1000 });
   await expect.poll(async () => (await list.locator("..").boundingBox())!.height).toBe(700);
 });
+
+test("staff customize the login space through the persistent file editor", async ({ page, signIn }) => {
+  await signIn("owner");
+  await page.goto("/admin/lobby?space=login");
+  await expect(page.getByRole("heading", { name: t("lobby:title"), exact: true })).toBeVisible();
+  const heading = page.getByLabel(t("lobby:bookHeading"));
+  await expect(heading).toBeVisible();
+  await heading.fill("Welcome to our network");
+  await page.getByRole("button", { name: t("lobby:save"), exact: true }).click();
+  await expect(page.getByText(t("lobby:saved"), { exact: true })).toBeVisible();
+  await page.reload();
+  await expect(heading).toHaveValue("Welcome to our network");
+});
+
+test("players cannot open the lobby administration page", async ({ page, signIn }) => {
+  await signIn("linked");
+  await page.goto("/admin/lobby");
+  await expect(page.getByRole("heading", { name: t("lobby:title"), exact: true })).toHaveCount(0);
+});

panel/src/App.tsx

@@ -59,6 +59,9 @@ const UsersPage = lazyWithReload(() =>
 const UserDetailPage = lazyWithReload(() =>
   import("@/pages/admin/UserDetailPage").then((m) => ({ default: m.UserDetailPage })),
 );
+const LobbyPage = lazyWithReload(() =>
+  import("@/pages/admin/LobbyPage").then((m) => ({ default: m.LobbyPage })),
+);
 const UpdatesPage = lazyWithReload(() =>
   import("@/pages/admin/UpdatesPage").then((m) => ({ default: m.UpdatesPage })),
 );
@@ -121,6 +124,7 @@ export default function App() {
                   so the section root and any stale bookmarks land somewhere useful. */}
               <Route path="admin" element={<RequireAdmin />}>
                 <Route index element={<Navigate to="/admin/images" replace />} />
+                <Route path="lobby" element={<LobbyPage />} />
                 <Route path="images" element={<ImageAdmin />} />
                 <Route path="builds" element={<ImageBuildPage />} />
                 <Route path="submissions" element={<SubmissionsPage />} />

panel/src/components/EditServerDialog.tsx

@@ -83,6 +83,7 @@ interface EditServerForm {
 
 interface Props {
   serverName: string;
+  systemService?: boolean;
   currentDisplayName?: string;
   currentPolicy?: AutostartPolicy;
   currentImage?: string;
@@ -97,6 +98,7 @@ interface Props {
 
 export function EditServerDialog({
   serverName,
+  systemService = false,
   currentDisplayName = "",
   currentPolicy = "ownerOnly",
   currentImage = "",
@@ -176,7 +178,7 @@ export function EditServerDialog({
       if (displayName !== currentDisplayName) {
         payload.displayName = displayName;
       }
-      if (form.autostartPolicy !== currentPolicy) {
+      if (!systemService && form.autostartPolicy !== currentPolicy) {
         payload.autostartPolicy = form.autostartPolicy;
       }
       if (imageChanged) {
@@ -190,7 +192,7 @@ export function EditServerDialog({
       if (cpu !== currentCpu) {
         payload.resources = { cpu };
       }
-      if (form.idleStop !== currentIdleStop) {
+      if (!systemService && form.idleStop !== currentIdleStop) {
         payload.idleStopSeconds = Number(form.idleStop);
       }
 
@@ -218,7 +220,7 @@ export function EditServerDialog({
           <div className="min-w-0 flex-1 text-left">
             <p className="text-sm font-medium">{t("edit_server_title")}</p>
             <p className="text-xs text-muted-foreground mt-0.5">
-              {t("edit_server_desc")}
+              {t(systemService ? "edit_system_desc" : "edit_server_desc")}
             </p>
           </div>
           <ChevronRight className="h-4 w-4 shrink-0 text-muted-foreground transition-transform group-hover:translate-x-0.5" />
@@ -228,7 +230,7 @@ export function EditServerDialog({
         <DialogHeader>
           <DialogTitle>{t("edit_server_title")}</DialogTitle>
           <DialogDescription>
-            {t("edit_server_desc_long")}
+            {t(systemService ? "edit_system_desc" : "edit_server_desc_long")}
           </DialogDescription>
         </DialogHeader>
 
@@ -350,6 +352,7 @@ export function EditServerDialog({
               <Label htmlFor="edit-server-policy">{t("create_server_policy")}</Label>
               <Select
                 value={form.autostartPolicy}
+                disabled={systemService}
                 onValueChange={(v) => set("autostartPolicy", v as AutostartPolicy)}
               >
                 <SelectTrigger id="edit-server-policy">
@@ -368,7 +371,7 @@ export function EditServerDialog({
 
           <div className="grid gap-2">
             <Label htmlFor="edit-server-idle">{t("edit_server_idle")}</Label>
-            <Select value={form.idleStop} onValueChange={(v) => set("idleStop", v)}>
+            <Select disabled={systemService} value={form.idleStop} onValueChange={(v) => set("idleStop", v)}>
               <SelectTrigger id="edit-server-idle">
                 <SelectValue />
               </SelectTrigger>

panel/src/i18n/index.ts

@@ -13,6 +13,8 @@ import enNavigation from "./resources/en-US/navigation.json";
 import enBackups from "./resources/en-US/backups.json";
 import enSubmissions from "./resources/en-US/submissions.json";
 import enFiles from "./resources/en-US/files.json";
+import enLobby from "./resources/en-US/lobby.json";
+import zhLobby from "./resources/zh-CN/lobby.json";
 import enSchedules from "./resources/en-US/schedules.json";
 import zhCommon from "./resources/zh-CN/common.json";
 import zhAuth from "./resources/zh-CN/auth.json";
@@ -46,6 +48,7 @@ export const i18nOptions: InitOptions = {
       submissions: enSubmissions,
       files: enFiles,
       schedules: enSchedules,
+      lobby: enLobby,
     },
     "zh-CN": {
       common: zhCommon,
@@ -61,6 +64,7 @@ export const i18nOptions: InitOptions = {
       submissions: zhSubmissions,
       files: zhFiles,
       schedules: zhSchedules,
+      lobby: zhLobby,
     },
   },
   supportedLngs: [...SUPPORTED_LANGUAGES],

panel/src/i18n/resources/en-US/lobby.json

@@ -0,0 +1,85 @@
+{
+  "title": "Login & lobby",
+  "subtitle": "Customize the scenes, guidance and rules players encounter when joining.",
+  "space_label": "Choose a space",
+  "login": "Login space",
+  "lobby": "Lobby",
+  "login_description": "Players authenticate here before entering the lobby. This Limbo scene uses a schematic, rather than a Paper world map.",
+  "lobby_description": "Players choose their server here. Replace maps, install plugins, customize the experience and grant builders access.",
+  "connection_version": "Installed game version: Java {{version}}",
+  "unknown_version": "not recorded",
+  "version_hint": "Client compatibility depends on proxy plugins. Version changes need matching login, lobby and proxy support; this is the installation version, while the running version comes from each image.",
+  "images_link": "Manage images & versions",
+  "stop_login": "Stop the login space to read and save settings. New players cannot join during maintenance; start it again when finished.",
+  "stop_lobby": "Stop the lobby to read and save settings. Back up its map before maintenance, then start it again when finished.",
+  "read_failed": "Could not read settings: {{reason}}. Check felis-experience.json in the file manager.",
+  "saved": "Saved. Start this space to apply the settings.",
+  "save": "Save settings",
+  "saving": "Saving…",
+  "invalid_values": "Check numeric ranges and selected options. Text is limited to 512 characters.",
+  "appearance": "Welcome & menu",
+  "players": "Player behavior & protection",
+  "world": "World environment",
+  "loginBook": "Login guidance & waiting",
+  "menuTitleZh": "Chinese menu title",
+  "menuTitleEn": "English menu title",
+  "welcomeZh": "Chinese welcome message",
+  "welcomeEn": "English welcome message",
+  "showWelcome": "Send a welcome message on join",
+  "openMenuOnJoin": "Open the server menu on join",
+  "gameMode": "Default player game mode",
+  "teleportOnJoin": "Return to world spawn on join",
+  "protectBuild": "Protect against building and damage",
+  "invulnerable": "Prevent player damage",
+  "disableHunger": "Prevent hunger",
+  "voidRescue": "Return to spawn after a void fall",
+  "difficulty": "Difficulty",
+  "time": "Fixed time (0–23999)",
+  "freezeTime": "Freeze world time",
+  "clearWeather": "Keep clear weather",
+  "pvp": "Allow PvP",
+  "spawnMobs": "Allow natural mob spawning",
+  "mobGriefing": "Allow mob griefing",
+  "tntExplodes": "Allow TNT explosions",
+  "keepInventory": "Keep inventory on death",
+  "immediateRespawn": "Respawn immediately",
+  "showAdvancementMessages": "Show advancement announcements",
+  "bookTitle": "Login book title",
+  "bookAuthor": "Login book author",
+  "bookHeading": "Login page heading",
+  "bookAction": "Login link text",
+  "bookHelp": "Login instructions",
+  "openBook": "Open the login book automatically",
+  "loginTimeoutSeconds": "Login timeout (30–3600 seconds)",
+  "login_settings_hint": "The system still generates the code and login URL and sends the chat guidance. An explicit login timeout environment variable takes precedence over this setting.",
+  "lobby_settings_hint": "The welcome message includes a clickable server menu. Spawn comes from the map; use setworldspawn x y z in the lobby console to change it. Protection switches apply across the lobby. Builders keep their own game mode.",
+  "ADVENTURE": "Adventure",
+  "SURVIVAL": "Survival",
+  "CREATIVE": "Creative",
+  "SPECTATOR": "Spectator",
+  "PEACEFUL": "Peaceful",
+  "EASY": "Easy",
+  "NORMAL": "Normal",
+  "HARD": "Hard",
+  "map_title": "Maps & scenes",
+  "login_map_hint": "Stop the login space, upload your scene as spawn.schem at the root, then start it. Adjust spawn coordinates in server.properties.",
+  "lobby_map_hint": "Stop the lobby, upload and extract a world ZIP at the root. The world folder must directly contain level.dat. Set level-name in server.properties, then start it. Back up the existing map first.",
+  "plugins_title": "Plugins & plugin settings",
+  "plugins_hint": "Upload plugin JARs and edit their configuration. Plugins must match the core and version of this space; bundled Felis plugins are refreshed from the image.",
+  "files_title": "Advanced file manager",
+  "files_hint": "Edit server properties, world settings and plugin data. Upload, extract, rename or download files. Authentication forwarding settings are maintained by the system.",
+  "console_title": "Console & runtime logs",
+  "console_hint": "Read logs, run lobby commands, set world spawn or manage players.",
+  "login_console_hint": "Read login runtime logs. Limbo has no RCON command channel; edit configuration in the file manager.",
+  "backups_title": "Map backups & restore",
+  "backups_hint": "Back up before replacing maps, plugins or images; choose a saved backup to restore.",
+  "builder_title": "Lobby builder access",
+  "builder_hint": "Grant felis.lobby.build to let a player build without opening building to everyone.",
+  "builder_player": "Minecraft player name",
+  "builder_grant": "Allow building",
+  "builder_revoke": "Deny building",
+  "builder_running": "Start the lobby before changing builder access.",
+  "discard_title": "Discard unsaved settings?",
+  "discard_hint": "Switching spaces discards your edits. Cancel to save them first.",
+  "discard": "Discard & switch"
+}

panel/src/i18n/resources/en-US/navigation.json

@@ -9,5 +9,6 @@
   "admin_images": "Images",
   "admin_builds": "Build Pipeline",
   "admin_submissions": "Submissions",
-  "admin_updates": "Maintenance & Backups"
+  "admin_updates": "Maintenance & Backups",
+  "admin_lobby": "Login & lobby"
 }

panel/src/i18n/resources/en-US/servers.json

@@ -64,7 +64,7 @@
   "schedules_link_title": "Scheduled tasks",
   "schedules_link_desc": "Restart, back up or run commands at set times.",
   "system_service": "System service",
-  "system_service_hint": "Provisioned and managed by the platform (felis systemservers); it accepts no user operations.",
+  "system_service_hint": "Staff manage system services in Login & lobby.",
   "players_back_to_console": "Back to console",
   "players_not_yours_title": "Not your server",
   "players_not_yours_body": "Only the owner or an admin can manage this server's players.",
@@ -268,5 +268,7 @@
   "migration_state_restoring": "Restoring and verifying target world",
   "migration_state_switching": "Switching active volume",
   "migration_state_succeeded": "Migration complete; start manually after inspection",
-  "migration_state_failed": "Migration failed; server remains stopped"
+  "migration_state_failed": "Migration failed; server remains stopped",
+  "system_customize": "Customize space",
+  "edit_system_desc": "Adjust the name, image and resources. A replacement must retain the Felis login or menu plugin and match the proxy protocol. System services do not stop when idle."
 }

panel/src/i18n/resources/zh-CN/lobby.json

@@ -0,0 +1,85 @@
+{
+  "title": "登录与大厅",
+  "subtitle": "设置玩家加入时看到的场景、提示和大厅规则。",
+  "space_label": "选择要自定义的空间",
+  "login": "登录空间",
+  "lobby": "正式大厅",
+  "login_description": "玩家先在这里验证身份，再进入正式大厅。登录场景使用 Limbo schematic，不能直接使用 Paper 世界地图。",
+  "lobby_description": "玩家在这里选择服务器。可以更换地图、安装插件、自定义大厅体验并授权建造。",
+  "connection_version": "安装时的游戏版本：Java {{version}}",
+  "unknown_version": "未记录",
+  "version_hint": "客户端版本兼容由代理插件决定。更换版本需配套更新登录空间、大厅镜像和代理；此处显示安装版本，实际版本以镜像为准。",
+  "images_link": "管理镜像与版本",
+  "stop_login": "停止登录空间后可读取和保存配置。维护期间新玩家无法进入；完成后请启动登录空间。",
+  "stop_lobby": "停止大厅后可读取和保存配置。维护前可先备份地图，完成后请启动大厅。",
+  "read_failed": "读取设置失败：{{reason}}。可在文件管理中检查 felis-experience.json。",
+  "saved": "已保存。启动该空间后生效。",
+  "save": "保存设置",
+  "saving": "正在保存…",
+  "invalid_values": "请检查数字范围和选项，文案最多 512 个字符。",
+  "appearance": "欢迎与菜单",
+  "players": "玩家行为与保护",
+  "world": "世界环境",
+  "loginBook": "登录提示与等待",
+  "menuTitleZh": "中文菜单标题",
+  "menuTitleEn": "英文菜单标题",
+  "welcomeZh": "中文欢迎文案",
+  "welcomeEn": "英文欢迎文案",
+  "showWelcome": "加入时发送欢迎提示",
+  "openMenuOnJoin": "加入时自动打开服务器菜单",
+  "gameMode": "玩家默认游戏模式",
+  "teleportOnJoin": "加入时回到世界出生点",
+  "protectBuild": "禁止普通玩家破坏和建造",
+  "invulnerable": "玩家免受伤害",
+  "disableHunger": "禁止饥饿",
+  "voidRescue": "掉入虚空时回到出生点",
+  "difficulty": "难度",
+  "time": "固定时间（0–23999）",
+  "freezeTime": "固定世界时间",
+  "clearWeather": "保持晴天",
+  "pvp": "允许 PvP",
+  "spawnMobs": "允许自然生成生物",
+  "mobGriefing": "允许生物破坏",
+  "tntExplodes": "允许 TNT 爆炸",
+  "keepInventory": "死亡后保留物品",
+  "immediateRespawn": "立即重生",
+  "showAdvancementMessages": "显示进度公告",
+  "bookTitle": "登录书标题",
+  "bookAuthor": "登录书作者",
+  "bookHeading": "登录书页标题",
+  "bookAction": "登录链接文案",
+  "bookHelp": "登录说明",
+  "openBook": "自动打开登录书",
+  "loginTimeoutSeconds": "登录等待时间（30–3600 秒）",
+  "login_settings_hint": "绑定码和登录链接始终由系统生成，聊天中的提示仍保留。部署中若显式设置登录超时环境变量，它优先于这里的等待时间。",
+  "lobby_settings_hint": "欢迎提示会附带可点击的服务器菜单。出生点使用地图保存的位置，可在大厅控制台用 setworldspawn x y z 设置。保护开关影响整个大厅；建造权限玩家保留自己的游戏模式。",
+  "ADVENTURE": "冒险",
+  "SURVIVAL": "生存",
+  "CREATIVE": "创造",
+  "SPECTATOR": "旁观",
+  "PEACEFUL": "和平",
+  "EASY": "简单",
+  "NORMAL": "普通",
+  "HARD": "困难",
+  "map_title": "地图与场景",
+  "login_map_hint": "停止登录空间，上传自定义场景为根目录的 spawn.schem，再启动。出生位置等设置在 server.properties 中调整。",
+  "lobby_map_hint": "停止大厅，上传世界 ZIP 并解压到根目录，确保世界目录直接包含 level.dat；在 server.properties 中设置 level-name 后启动。建议先备份现有地图。",
+  "plugins_title": "插件与插件配置",
+  "plugins_hint": "上传插件 JAR、编辑插件配置。插件需适配该空间的核心与版本；系统自带的 Felis 插件会随镜像更新。",
+  "files_title": "高级文件管理",
+  "files_hint": "编辑服务器属性、世界配置和插件数据，上传、解压、重命名或下载文件。认证转发设置由系统维护。",
+  "console_title": "控制台与运行日志",
+  "console_hint": "查看日志，执行大厅命令、设置出生点或管理玩家。",
+  "login_console_hint": "查看登录空间日志。Limbo 不支持 RCON 命令，请通过文件管理修改配置。",
+  "backups_title": "地图备份与恢复",
+  "backups_hint": "更换地图、插件或镜像前保存备份；可选择已有备份恢复。",
+  "builder_title": "大厅建造权限",
+  "builder_hint": "授予 felis.lobby.build 后，该玩家可在大厅建造，不必开放所有人的建造权限。",
+  "builder_player": "Minecraft 角色名",
+  "builder_grant": "允许建造",
+  "builder_revoke": "禁止建造",
+  "builder_running": "请先启动大厅，才能修改建造权限。",
+  "discard_title": "放弃未保存的设置？",
+  "discard_hint": "切换空间会丢失本次编辑。可以取消后先保存。",
+  "discard": "放弃并切换"
+}

panel/src/i18n/resources/zh-CN/navigation.json

@@ -9,5 +9,6 @@
   "admin_images": "镜像",
   "admin_builds": "构建流水线",
   "admin_submissions": "审核提交",
-  "admin_updates": "维护与备份"
+  "admin_updates": "维护与备份",
+  "admin_lobby": "登录与大厅"
 }

panel/src/i18n/resources/zh-CN/servers.json

@@ -64,7 +64,7 @@
   "schedules_link_title": "计划任务",
   "schedules_link_desc": "定时重启、备份或执行命令。",
   "system_service": "系统服务",
-  "system_service_hint": "由平台预置并管理（felis systemservers），不接受用户操作。",
+  "system_service_hint": "系统服务由管理员在“登录与大厅”中管理。",
   "players_back_to_console": "返回控制台",
   "players_not_yours_title": "这不是你的服务器",
   "players_not_yours_body": "只有所有者或管理员才能管理此服务器的玩家。",
@@ -267,5 +267,7 @@
   "migration_state_restoring": "正在恢复并校验目标卷",
   "migration_state_switching": "正在切换活动卷",
   "migration_state_succeeded": "迁移完成，等待手动启动",
-  "migration_state_failed": "迁移失败，服务器保持停服"
+  "migration_state_failed": "迁移失败，服务器保持停服",
+  "system_customize": "自定义大厅",
+  "edit_system_desc": "调整名称、镜像与资源。更换镜像需保留 Felis 登录或菜单插件，并保持与代理的版本兼容。系统服务不自动休眠。"
 }

panel/src/lib/experience.ts

@@ -0,0 +1,95 @@
+import { api } from "./api";
+import type { ApiError } from "./types";
+
+export const EXPERIENCE_PATH = "felis-experience.json";
+export type Experience = Record<string, unknown>;
+export type ExperienceField = {
+  key: string;
+  value: string | number | boolean;
+  choices?: string[];
+  min?: number;
+  max?: number;
+  multiline?: boolean;
+};
+export type ExperienceGroup = { key: string; fields: ExperienceField[] };
+
+export const LOBBY_GROUPS: ExperienceGroup[] = [
+  { key: "appearance", fields: [
+    { key: "menuTitleZh", value: "Felis 服务器" },
+    { key: "menuTitleEn", value: "Felis Servers" },
+    { key: "welcomeZh", value: "欢迎来到大厅。输入 /menu 或点击 " },
+    { key: "welcomeEn", value: "Welcome to the lobby. Type /menu or click " },
+    { key: "showWelcome", value: true },
+    { key: "openMenuOnJoin", value: false },
+  ] },
+  { key: "players", fields: [
+    { key: "gameMode", value: "ADVENTURE", choices: ["ADVENTURE", "SURVIVAL", "CREATIVE", "SPECTATOR"] },
+    { key: "teleportOnJoin", value: true },
+    { key: "protectBuild", value: true },
+    { key: "invulnerable", value: true },
+    { key: "disableHunger", value: true },
+    { key: "voidRescue", value: true },
+  ] },
+  { key: "world", fields: [
+    { key: "difficulty", value: "PEACEFUL", choices: ["PEACEFUL", "EASY", "NORMAL", "HARD"] },
+    { key: "time", value: 6000, min: 0, max: 23999 },
+    { key: "freezeTime", value: true },
+    { key: "clearWeather", value: true },
+    { key: "pvp", value: false },
+    { key: "spawnMobs", value: false },
+    { key: "mobGriefing", value: false },
+    { key: "tntExplodes", value: false },
+    { key: "keepInventory", value: true },
+    { key: "immediateRespawn", value: true },
+    { key: "showAdvancementMessages", value: false },
+  ] },
+];
+
+export const LOGIN_GROUPS: ExperienceGroup[] = [
+  { key: "loginBook", fields: [
+    { key: "bookTitle", value: "Felis Login" },
+    { key: "bookAuthor", value: "Felis" },
+    { key: "bookHeading", value: "Felis 登录 / Login" },
+    { key: "bookAction", value: "▶ 点此打开登录页\n▶ Open login page", multiline: true },
+    { key: "bookHelp", value: "在系统浏览器中完成。\nUse your SYSTEM browser —\nnot WeChat / QQ (passkey\nwon't work there).", multiline: true },
+    { key: "openBook", value: true },
+    { key: "loginTimeoutSeconds", value: 600, min: 30, max: 3600 },
+  ] },
+];
+
+export function experienceValid(values: Experience, groups: ExperienceGroup[]): boolean {
+  return groups.flatMap((g) => g.fields).every((field) => {
+    const value = values[field.key] ?? field.value;
+    if (typeof value !== typeof field.value) return false;
+    if (typeof value === "number") return Number.isInteger(value) && value >= field.min! && value <= field.max!;
+    if (typeof value === "string") return value.length <= 512 && (!field.choices || field.choices.includes(value));
+    return true;
+  });
+}
+
+export async function readExperience(name: string, groups: ExperienceGroup[]): Promise<{ values: Experience; sha256: string }> {
+  let file;
+  try {
+    file = await api.readServerFile(name, EXPERIENCE_PATH);
+  } catch (error) {
+    if ((error as ApiError)?.code === "not_found") return { values: {}, sha256: "" };
+    throw error;
+  }
+  const bytes = Uint8Array.from(atob(file.content), (char) => char.charCodeAt(0));
+  const values: unknown = JSON.parse(new TextDecoder("utf-8", { fatal: true }).decode(bytes));
+  if (!values || typeof values !== "object" || Array.isArray(values) || !experienceValid(values as Experience, groups)) {
+    throw new Error("invalid_experience");
+  }
+  return { values: values as Experience, sha256: file.sha256 };
+}
+
+export async function writeExperience(name: string, values: Experience, sha256: string): Promise<string> {
+  const bytes = new TextEncoder().encode(JSON.stringify(values, null, 2) + "\n");
+  let binary = "";
+  for (const byte of bytes) binary += String.fromCharCode(byte);
+  const content = btoa(binary);
+  const file = sha256
+    ? await api.writeServerFile(name, EXPERIENCE_PATH, content, sha256)
+    : await api.createServerFile(name, EXPERIENCE_PATH, content);
+  return file.sha256;
+}

panel/src/lib/nav.ts

@@ -1,4 +1,5 @@
 import {
+  DoorOpen,
   LayoutDashboard,
   Server,
   UserRound,
@@ -61,6 +62,7 @@ export const NAV_SECTIONS: NavSection[] = [
     adminOnly: true,
     ownerOnly: false,
     items: [
+      { to: "/admin/lobby", key: "admin_lobby", icon: DoorOpen },
       { to: "/admin/images", key: "admin_images", icon: Boxes },
       { to: "/admin/builds", key: "admin_builds", icon: Cpu },
       { to: "/admin/submissions", key: "admin_submissions", icon: ClipboardCheck },

panel/src/lib/openapi.gen.ts

@@ -1378,7 +1378,7 @@ export interface paths {
         put?: never;
         /**
          * Start downloading one backup (owner-or-admin plus a former-owner match).
-         * @description Starts a Job that reads the archive from the backup store and hands it to felis-api, which streams it to the browser (poll GET /exports/{ticket}, then open its download). The Job checks the archive against the sha256 recorded when it was written as it streams; a mismatch cuts the download off short of its end. On the way out config/paper-global.yml (the cluster's forwarding secret) is left out and server.properties has its rcon.password redacted, so the download carries no Content-Length. A user gets 404 for a backup outside their scope, as their list never shows it. One export per user at a time, 2 across the install, 6 per user per hour.
+         * @description Starts a Job that reads the archive from the backup store and hands it to felis-api, which streams it to the browser (poll GET /exports/{ticket}, then open its download). The Job checks the archive against the sha256 recorded when it was written as it streams; a mismatch cuts the download off short of its end. On the way out config/paper-global.yml (the cluster's forwarding secret) is left out and server.properties has its rcon.password and forwarding-secrets redacted, so the download carries no Content-Length. A user gets 404 for a backup outside their scope, as their list never shows it. One export per user at a time, 2 across the install, 6 per user per hour.
          */
         post: operations["exportBackup"];
         delete?: never;
@@ -1566,7 +1566,7 @@ export interface paths {
         put?: never;
         /**
          * Start downloading one file or folder of a stopped server's world (owner-or-admin).
-         * @description An export (poll GET /exports/{ticket}, then open its download): a Job reads the file, or zips the folder, from the world volume read-only and hands it to felis-api, which streams it to the browser. A file saves under its own name with its length; a folder as NAME.zip, streamed without one, with symbolic links, devices and sockets left out. config/paper-global.yml, the cluster's forwarding secret, is refused as a file and left out of a folder, and server.properties goes out with its rcon.password redacted; both are matched by the file itself, so a link to either under another name is guarded too. The server cannot start until the download has ended. Two file downloads per user at a time, 4 across the install, 30 per user per hour, counted apart from world and backup exports. Audited as file.download.
+         * @description An export (poll GET /exports/{ticket}, then open its download): a Job reads the file, or zips the folder, from the world volume read-only and hands it to felis-api, which streams it to the browser. A file saves under its own name with its length; a folder as NAME.zip, streamed without one, with symbolic links, devices and sockets left out. config/paper-global.yml, the cluster's forwarding secret, is refused as a file and left out of a folder, and server.properties goes out with its rcon.password and forwarding-secrets redacted; both are matched by the file itself, so a link to either under another name is guarded too. The server cannot start until the download has ended. Two file downloads per user at a time, 4 across the install, 30 per user per hour, counted apart from world and backup exports. Audited as file.download.
          */
         post: operations["downloadServerFile"];
         delete?: never;
@@ -3035,7 +3035,7 @@ export interface components {
             claimable: boolean;
             /** @description Present and true when the owner lookup failed, so an absent owner says nothing about whether the server is claimed. */
             ownerUnknown?: boolean;
-            /** @description True for a platform-provisioned system service (the login gate, the lobby). Their reserved names are rejected by every per-server route, so the cockpit renders them read-only instead of offering actions that would 400. */
+            /** @description True for a platform-provisioned system service (the login gate, the lobby). Staff can manage them through the existing server routes; players see them read-only. Creating, claiming and deleting these reserved names remain prohibited. */
             system?: boolean;
         };
         /** @description A pending retirement (internal/api/repo.go RetireState): the owner gave the server up, or with delete an admin is deleting it. The reaper carries it out on its next daily run: it archives the world as a released backup, deletes the world volume and releases the server, and for a deletion also removes it. Until then the server stays stopped and cannot be woken or claimed. */
@@ -4921,6 +4921,7 @@ export interface operations {
                     };
                 };
             };
+            400: components["responses"]["BadRequest"];
             401: components["responses"]["Unauthorized"];
             403: components["responses"]["Forbidden"];
             404: components["responses"]["NotFound"];
@@ -4950,6 +4951,7 @@ export interface operations {
                     };
                 };
             };
+            400: components["responses"]["BadRequest"];
             401: components["responses"]["Unauthorized"];
             /** @description Quota exceeded. */
             403: {
@@ -5627,6 +5629,7 @@ export interface operations {
                     "application/json": components["schemas"]["ServerInfo"];
                 };
             };
+            400: components["responses"]["BadRequest"];
             401: components["responses"]["Unauthorized"];
             403: components["responses"]["Forbidden"];
             404: components["responses"]["NotFound"];
@@ -7256,7 +7259,7 @@ export interface operations {
                          * @description Base64-encoded file bytes.
                          */
                         content: string;
-                        /** @description SHA-256 of the file as stored (before the rcon.password redaction in server.properties). Send it back as expect_sha256 on the next write. */
+                        /** @description SHA-256 of the file as stored (before secret redaction in server.properties). Send it back as expect_sha256 on the next write. */
                         sha256: string;
                         /** @description SHA-256 of the decoded content as sent (after any redaction). A client that gets content hashing otherwise got it damaged on the way, and reads it again. */
                         content_sha256: string;

panel/src/pages/ServerConsole.tsx

@@ -340,6 +340,7 @@ export function ServerConsole() {
               {isAdmin && (
                 <EditServerDialog
                   serverName={name}
+                  systemService={name === "login" || name === "lobby"}
                   currentDisplayName={data.displayName}
                   currentPolicy={data.autostartPolicy as AutostartPolicy}
                   currentImage={data.image}

panel/src/pages/ServerFiles.tsx

@@ -1,5 +1,5 @@
 import { useCallback, useEffect, useRef, useState } from "react";
-import { useParams } from "react-router-dom";
+import { useParams, useSearchParams } from "react-router-dom";
 import {
   AlertTriangle,
   ArrowUp,
@@ -115,6 +115,7 @@ type Naming =
  *  instead of letting each call fail. */
 export function ServerFiles() {
   const { name = "" } = useParams();
+  const [params] = useSearchParams();
   const { t, i18n } = useTranslation("files");
   const locale = i18n.language;
   const { isAdmin, loading: tierLoading } = useTier();
@@ -128,7 +129,7 @@ export function ServerFiles() {
   const owned = canManage(isAdmin, mineQ.data, name);
   const stopped = statusQ.data?.phase === "Stopped";
 
-  const [dir, setDir] = useState("");
+  const [dir, setDir] = useState(params.get("path") ?? "");
   const [entries, setEntries] = useState<ServerFileEntry[] | null>(null);
   const [truncated, setTruncated] = useState(false);
   const [listErr, setListErr] = useState<unknown>(null);

panel/src/pages/admin/LobbyPage.test.tsx

@@ -0,0 +1,83 @@
+// @vitest-environment jsdom
+import { beforeEach, describe, expect, it, vi } from "vitest";
+import { fireEvent, render, screen, waitFor } from "@testing-library/react";
+import userEvent from "@testing-library/user-event";
+import { MemoryRouter } from "react-router-dom";
+import { LobbyPage } from "./LobbyPage";
+
+const calls = vi.hoisted(() => ({
+  status: vi.fn(), listImages: vi.fn(), readServerFile: vi.fn(), writeServerFile: vi.fn(), createServerFile: vi.fn(), accessPermission: vi.fn(),
+}));
+vi.mock("@/lib/api", async (original) => ({ ...await original<typeof import("@/lib/api")>(), api: calls }));
+vi.mock("@/lib/config", async (original) => ({ ...await original<typeof import("@/lib/config")>(), loadConfig: () => Promise.resolve({ apiBase: "/api/v1", rootDomain: "example.test", gameVersion: "26.3" }) }));
+
+beforeEach(() => {
+  vi.clearAllMocks();
+  calls.status.mockImplementation(async (name) => ({ name, subdomain: name, phase: "Stopped", desiredState: "Stopped", ready: false, reaperExempt: true, playersOnline: 0, playersMax: 200 }));
+  calls.listImages.mockResolvedValue([]);
+  calls.readServerFile.mockResolvedValue({ content: btoa(JSON.stringify({ menuTitleEn: "Old title", customPlugin: { enabled: true } })), sha256: "read-hash" });
+  calls.writeServerFile.mockResolvedValue({ sha256: "saved-hash" });
+  calls.createServerFile.mockResolvedValue({ sha256: "saved-hash" });
+});
+
+function page(space = "lobby") {
+  render(<MemoryRouter initialEntries={[`/admin/lobby?space=${space}`]}><LobbyPage /></MemoryRouter>);
+}
+
+describe("LobbyPage", () => {
+  it("saves with the read hash and preserves unknown plugin settings", async () => {
+    page();
+    fireEvent.change(await screen.findByLabelText("English menu title"), { target: { value: "My Network" } });
+    await userEvent.click(screen.getByRole("button", { name: "Save settings" }));
+    await screen.findByText("Saved. Start this space to apply the settings.");
+    const [name, path, content, hash] = calls.writeServerFile.mock.calls[0];
+    expect([name, path, hash]).toEqual(["lobby", "felis-experience.json", "read-hash"]);
+    expect(JSON.parse(atob(content))).toEqual({ menuTitleEn: "My Network", customPlugin: { enabled: true } });
+  });
+
+  it("uses defaults for a missing file and creates without overwriting a concurrent file", async () => {
+    calls.readServerFile.mockRejectedValue({ status: 404, code: "not_found" });
+    page("login");
+    fireEvent.change(await screen.findByLabelText("Login timeout (30–3600 seconds)"), { target: { value: "900" } });
+    await userEvent.click(screen.getByRole("button", { name: "Save settings" }));
+    await waitFor(() => expect(calls.createServerFile).toHaveBeenCalled());
+    expect(calls.createServerFile.mock.calls[0].slice(0, 2)).toEqual(["login", "felis-experience.json"]);
+    expect(calls.writeServerFile).not.toHaveBeenCalled();
+  });
+
+  it("requires a stop before reading or writing a running space", async () => {
+    calls.status.mockResolvedValue({ name: "lobby", phase: "Running", desiredState: "Running", ready: true });
+    page();
+    await screen.findByText(/Stop the lobby to read and save settings/);
+    expect(calls.readServerFile).not.toHaveBeenCalled();
+    expect(screen.queryByRole("button", { name: "Save settings" })).toBeNull();
+  });
+
+  it("keeps the draft when another editor changed the file", async () => {
+    calls.writeServerFile.mockRejectedValue({ status: 409, code: "file_changed" });
+    page();
+    fireEvent.change(await screen.findByLabelText("English menu title"), { target: { value: "My Network" } });
+    await userEvent.click(screen.getByRole("button", { name: "Save settings" }));
+    await screen.findByRole("alert");
+    expect((screen.getByLabelText("English menu title") as HTMLInputElement).value).toBe("My Network");
+    expect(calls.createServerFile).not.toHaveBeenCalled();
+  });
+
+  it("confirms a switch with unsaved edits", async () => {
+    page();
+    fireEvent.change(await screen.findByLabelText("English menu title"), { target: { value: "My Network" } });
+    await userEvent.click(screen.getByRole("button", { name: "Login space" }));
+    await screen.findByRole("dialog", { name: "Discard unsaved settings?" });
+    expect(calls.status).not.toHaveBeenCalledWith("login");
+    await userEvent.click(screen.getByRole("button", { name: "Discard & switch" }));
+    await screen.findByLabelText("Login book title");
+    expect(calls.writeServerFile).not.toHaveBeenCalled();
+  });
+
+  it("does not offer to save malformed JSON", async () => {
+    calls.readServerFile.mockResolvedValue({ content: btoa("{broken"), sha256: "hash" });
+    page();
+    await screen.findByRole("alert");
+    expect(screen.queryByRole("button", { name: "Save settings" })).toBeNull();
+  });
+});

panel/src/pages/admin/LobbyPage.tsx

@@ -0,0 +1,182 @@
+import { useEffect, useState } from "react";
+import { Link, useSearchParams } from "react-router-dom";
+import { DoorOpen, FolderOpen, Map, Package, Save, Shield, Terminal } from "lucide-react";
+import { useTranslation } from "react-i18next";
+import { ConfirmDialog } from "@/components/ConfirmDialog";
+import { PageHeader } from "@/components/PageHeader";
+import { Card, CardContent, CardHeader, CardTitle } from "@/components/ui/card";
+import { Button } from "@/components/ui/button";
+import { Input } from "@/components/ui/input";
+import { Label } from "@/components/ui/label";
+import { PhaseBadge, shownPhase, startFailure } from "@/components/PhaseBadge";
+import { PowerButton } from "@/components/PowerButton";
+import { CopyAddress } from "@/components/CopyAddress";
+import { EditServerDialog } from "@/components/EditServerDialog";
+import { ErrorState, Loading } from "@/components/States";
+import { InlineError, MessageLine } from "@/components/MessageLine";
+import { api, humanizeError } from "@/lib/api";
+import { joinAddress } from "@/lib/config";
+import { STATUS_POLL_FAST_MS, useAsync, useConfig, usePolling, useUnsavedGuard } from "@/lib/hooks";
+import { experienceValid, LOGIN_GROUPS, LOBBY_GROUPS, readExperience, writeExperience, type Experience } from "@/lib/experience";
+
+function ExperienceSettings({ name, stopped, onDirtyChange }: { name: string; stopped: boolean; onDirtyChange: (dirty: boolean) => void }) {
+  const { t } = useTranslation("lobby");
+  const groups = name === "login" ? LOGIN_GROUPS : LOBBY_GROUPS;
+  const query = useAsync(() => stopped ? readExperience(name, groups) : Promise.resolve(null), [name, stopped]);
+  const [draft, setDraft] = useState<{ values: Experience; original: string; sha256: string } | null>(null);
+  const [saving, setSaving] = useState(false);
+  const [message, setMessage] = useState<{ kind: "error" | "success"; text: string } | null>(null);
+  useEffect(() => {
+    if (query.data && !draft) {
+      setDraft({ ...query.data, original: JSON.stringify(query.data.values) });
+    }
+  }, [query.data, draft]);
+  const dirty = draft !== null && JSON.stringify(draft.values) !== draft.original;
+  useUnsavedGuard(dirty);
+  useEffect(() => onDirtyChange(dirty), [dirty, onDirtyChange]);
+
+  async function save() {
+    if (!draft || !stopped || saving || !experienceValid(draft.values, groups)) return;
+    setSaving(true);
+    setMessage(null);
+    try {
+      const sha256 = await writeExperience(name, draft.values, draft.sha256);
+      setDraft({ ...draft, original: JSON.stringify(draft.values), sha256 });
+      setMessage({ kind: "success", text: t("saved") });
+    } catch (error) {
+      setMessage({ kind: "error", text: humanizeError(error) });
+    } finally {
+      setSaving(false);
+    }
+  }
+
+  return (
+    <div className="space-y-4">
+      {!stopped && <p className="rounded-md border border-amber-500/30 bg-amber-500/10 p-4 text-sm">{t(name === "login" ? "stop_login" : "stop_lobby")}</p>}
+      {stopped && query.loading && !draft && <Loading />}
+      {query.error != null && <ErrorState error={t("read_failed", { reason: humanizeError(query.error) })} onRetry={query.reload} />}
+      {draft && groups.map((group) => (
+        <Card key={group.key}>
+          <CardHeader><CardTitle>{t(group.key)}</CardTitle></CardHeader>
+          <CardContent className="grid gap-4 sm:grid-cols-2">
+            {group.fields.map((field) => {
+              const value = draft.values[field.key] ?? field.value;
+              const id = `experience-${field.key}`;
+              const set = (next: unknown) => setDraft({ ...draft, values: { ...draft.values, [field.key]: next } });
+              if (typeof field.value === "boolean") return (
+                <label key={id} className="flex min-h-11 items-center gap-3 rounded-md border border-border px-3 text-sm" htmlFor={id}>
+                  <input id={id} type="checkbox" checked={value as boolean} onChange={(e) => set(e.target.checked)} disabled={!stopped || saving} className="h-4 w-4 accent-primary" />
+                  {t(field.key)}
+                </label>
+              );
+              return (
+                <div key={id} className="grid min-w-0 gap-2">
+                  <Label htmlFor={id}>{t(field.key)}</Label>
+                  {field.choices ? (
+                    <select id={id} value={value as string} onChange={(e) => set(e.target.value)} disabled={!stopped || saving} className="h-10 w-full rounded-md border border-input bg-background px-3 text-sm">
+                      {field.choices.map((choice) => <option key={choice} value={choice}>{t(choice)}</option>)}
+                    </select>
+                  ) : field.multiline ? (
+                    <textarea id={id} value={value as string} maxLength={512} onChange={(e) => set(e.target.value)} disabled={!stopped || saving} className="min-h-24 w-full rounded-md border border-input bg-background p-3 text-sm" />
+                  ) : (
+                    <Input id={id} type={typeof field.value === "number" ? "number" : "text"} value={value as string | number} min={field.min} max={field.max} step={1} maxLength={512} onChange={(e) => set(typeof field.value === "number" ? (e.target.value === "" ? "" : Number(e.target.value)) : e.target.value)} disabled={!stopped || saving} />
+                  )}
+                </div>
+              );
+            })}
+          </CardContent>
+        </Card>
+      ))}
+      {draft && <>
+        <p className="text-sm text-muted-foreground">{t(name === "login" ? "login_settings_hint" : "lobby_settings_hint")}</p>
+        {message && <MessageLine kind={message.kind} message={message.text} />}
+        {!experienceValid(draft.values, groups) && <InlineError message={t("invalid_values")} />}
+        <Button onClick={() => void save()} disabled={!stopped || !dirty || saving || !experienceValid(draft.values, groups)}><Save className="h-4 w-4" />{t(saving ? "saving" : "save")}</Button>
+      </>}
+    </div>
+  );
+}
+
+function BuilderAccess({ ready }: { ready: boolean }) {
+  const { t } = useTranslation("lobby");
+  const [player, setPlayer] = useState("");
+  const [busy, setBusy] = useState(false);
+  const [message, setMessage] = useState<{ kind: "error" | "success"; text: string } | null>(null);
+  async function grant(value: boolean) {
+    setBusy(true);
+    setMessage(null);
+    try {
+      const result = await api.accessPermission("lobby", "set", player.trim(), "felis.lobby.build", value);
+      setMessage({ kind: "success", text: result.output });
+    } catch (error) {
+      setMessage({ kind: "error", text: humanizeError(error) });
+    } finally {
+      setBusy(false);
+    }
+  }
+  return <Card>
+    <CardHeader><CardTitle>{t("builder_title")}</CardTitle></CardHeader>
+    <CardContent className="space-y-3">
+      <p className="text-sm text-muted-foreground">{t("builder_hint")}</p>
+      <Label htmlFor="builder-player">{t("builder_player")}</Label>
+      <Input id="builder-player" value={player} onChange={(e) => setPlayer(e.target.value)} placeholder="Steve" />
+      <div className="flex flex-wrap gap-2">
+        <Button disabled={!ready || busy || !/^[A-Za-z0-9_]{1,16}$/.test(player.trim())} onClick={() => void grant(true)}>{t("builder_grant")}</Button>
+        <Button variant="outline" disabled={!ready || busy || !/^[A-Za-z0-9_]{1,16}$/.test(player.trim())} onClick={() => void grant(false)}>{t("builder_revoke")}</Button>
+      </div>
+      {!ready && <p className="text-sm text-muted-foreground">{t("builder_running")}</p>}
+      {message && <MessageLine kind={message.kind} message={message.text} />}
+    </CardContent>
+  </Card>;
+}
+
+export function LobbyPage() {
+  const { t } = useTranslation("lobby");
+  const [params, setParams] = useSearchParams();
+  const name = params.get("space") === "login" ? "login" : "lobby";
+  const [dirty, setDirty] = useState(false);
+  const [nextSpace, setNextSpace] = useState<string | null>(null);
+  const cfg = useConfig();
+  const status = useAsync(() => api.status(name), [name]);
+  usePolling(status.reload, STATUS_POLL_FAST_MS);
+  const data = status.data;
+  const links = [
+    { icon: Map, title: "map_title", hint: name === "login" ? "login_map_hint" : "lobby_map_hint", to: `/servers/${name}/files` },
+    { icon: Package, title: "plugins_title", hint: "plugins_hint", to: `/servers/${name}/files?path=plugins` },
+    { icon: FolderOpen, title: "files_title", hint: "files_hint", to: `/servers/${name}/files` },
+    { icon: Terminal, title: "console_title", hint: name === "login" ? "login_console_hint" : "console_hint", to: `/servers/${name}` },
+    { icon: Shield, title: "backups_title", hint: "backups_hint", to: `/servers/${name}/backups` },
+  ];
+  return <div className="space-y-6">
+    <PageHeader icon={DoorOpen} title={t("title")} subtitle={t("subtitle")} />
+    <Card><CardContent className="flex flex-wrap items-center justify-between gap-4 pt-5">
+      <div className="space-y-1">
+        <p className="text-sm font-medium">{t("connection_version", { version: cfg?.gameVersion ?? t("unknown_version") })}</p>
+        {cfg && <CopyAddress address={joinAddress("login", cfg)} />}
+        <p className="max-w-2xl text-xs text-muted-foreground">{t("version_hint")}</p>
+      </div>
+      <Link to="/admin/images" className="text-sm text-primary hover:underline">{t("images_link")}</Link>
+    </CardContent></Card>
+    <div className="flex flex-wrap gap-2" aria-label={t("space_label")}>
+      {(["lobby", "login"] as const).map((space) => <Button key={space} variant={name === space ? "default" : "outline"} aria-pressed={name === space} onClick={() => { if (space !== name) { if (dirty) setNextSpace(space); else setParams({ space }); } }}>{t(space)}</Button>)}
+    </div>
+    <p className="text-sm text-muted-foreground">{t(`${name}_description`)}</p>
+    {status.loading && !data && <Loading />}
+    {status.error != null && <ErrorState error={humanizeError(status.error)} onRetry={status.reload} />}
+    {data && <>
+      <div className="flex flex-wrap items-center justify-between gap-3 rounded-lg border border-border bg-card p-4">
+        <div className="min-w-0 space-y-2"><div className="flex flex-wrap items-center gap-3"><h2 className="font-semibold">{data.displayName || t(name)}</h2><PhaseBadge phase={shownPhase(data)} /></div><p className="break-all text-xs text-muted-foreground">{data.image}</p></div>
+        <PowerButton name={name} phase={data.phase} desiredState={data.desiredState} failed={startFailure(data) !== null} playersOnline={data.playersOnline} playerCountUnknown={data.playerCountUnknown} onChanged={status.reload} />
+      </div>
+      <div className="grid items-start gap-6 lg:grid-cols-[minmax(0,2fr)_minmax(0,1fr)]">
+        <ExperienceSettings key={name} name={name} onDirtyChange={setDirty} stopped={data.phase === "Stopped" && data.desiredState === "Stopped"} />
+        <div className="space-y-4">
+          {links.map(({ icon: Icon, title, hint, to }) => <Link key={title} to={to} className="flex gap-3 rounded-lg border border-border bg-card p-4 hover:border-primary/40"><Icon className="mt-0.5 h-5 w-5 shrink-0 text-primary" /><div className="min-w-0"><p className="text-sm font-medium">{t(title)}</p><p className="mt-1 text-xs text-muted-foreground">{t(hint)}</p></div></Link>)}
+          <EditServerDialog serverName={name} systemService currentDisplayName={data.displayName} currentPolicy={data.autostartPolicy} currentImage={data.image} currentMemory={data.memory} currentStorage={data.storageSize} currentCpu={data.cpu} currentIdleStopSeconds={0} onUpdated={status.reload} />
+          {name === "lobby" && <BuilderAccess ready={data.ready} />}
+        </div>
+      </div>
+    </>}
+    <ConfirmDialog open={nextSpace !== null} onOpenChange={(open) => { if (!open) setNextSpace(null); }} title={t("discard_title")} description={t("discard_hint")} confirmLabel={t("discard")} onConfirm={async () => { if (nextSpace) { setParams({ space: nextSpace }); setDirty(false); setNextSpace(null); } }} />
+  </div>;
+}

panel/src/pages/servers/ServersPage.tsx

@@ -532,8 +532,8 @@ function ServerActions({
   }
 
   if (server.system) {
-    // A system service carries a reserved name that every per-server route
-    // rejects, so offer no actions — just the honest label.
+    // Staff customize system services in the dedicated lobby view.
+    if (isAdmin) return <Link className="text-sm text-primary hover:underline" to={`/admin/lobby?space=${server.name}`}>{ts("system_customize")}</Link>;
     return (
       <span className="text-xs text-muted-foreground/70" title={ts("system_service_hint")}>
         {ts("system_service")}

plugins/limbo/src/main/java/best/lolicon/felis/limbo/FelisLimboPlugin.java

@@ -5,6 +5,7 @@ import best.lolicon.felis.link.FelisApiClient;
 import best.lolicon.felis.link.LinkClient;
 import best.lolicon.felis.link.LinkCode;
 import best.lolicon.felis.link.LinkConfig;
+import best.lolicon.felis.link.ExperienceConfig;
 import best.lolicon.felis.link.LinkConfigLoader;
 
 import com.loohp.limbo.events.EventHandler;
@@ -92,6 +93,7 @@ public final class FelisLimboPlugin extends LimboPlugin implements Listener {
 
     private volatile Readiness readiness;
     private volatile LoginFlow flow;
+    private ExperienceConfig experience;
 
     @Override
     public void onEnable() {
@@ -146,6 +148,7 @@ public final class FelisLimboPlugin extends LimboPlugin implements Listener {
         try {
             File props = new File(getDataFolder(), "felis-link.properties");
             cfg = LinkConfigLoader.load(props.toPath());
+            experience = ExperienceConfig.load(ExperienceConfig.PATH);
         } catch (IOException e) {
             // Missing/half config: like the other Felis plugins, load un-crippled —
             // readiness stays up, the login flow just never turns on.
@@ -161,7 +164,9 @@ public final class FelisLimboPlugin extends LimboPlugin implements Listener {
         }
         String consoleUrl = "https://" + panelHost;
         String lobby = GateConfig.lobby(System.getenv("FELIS_LOBBY_SERVER"));
-        long timeoutMillis = GateConfig.loginTimeoutSeconds(System.getenv("FELIS_LOGIN_TIMEOUT_SECONDS")) * 1000L;
+        long timeoutMillis = GateConfig.loginTimeoutSeconds(System.getenv("FELIS_LOGIN_TIMEOUT_SECONDS") != null
+                ? System.getenv("FELIS_LOGIN_TIMEOUT_SECONDS")
+                : Long.toString(experience.number("loginTimeoutSeconds", GateConfig.DEFAULT_TIMEOUT_SECONDS))) * 1000L;
         this.flow = new LoginFlow(new LimboGate(), new FelisApiClient(cfg), new LinkClient(cfg),
                 consoleUrl, timeoutMillis, System::currentTimeMillis, LOG);
         LOG.info("FelisLimbo: login flow ON — console=" + consoleUrl
@@ -187,7 +192,7 @@ public final class FelisLimboPlugin extends LimboPlugin implements Listener {
         @Override
         public LoginFlow.Seat player(UUID id) {
             Player player = getServer().getPlayer(id);
-            return player != null && player.isValid() ? new LimboSeat(player) : null;
+            return player != null && player.isValid() ? new LimboSeat(player, experience) : null;
         }
 
         @Override
@@ -222,7 +227,7 @@ public final class FelisLimboPlugin extends LimboPlugin implements Listener {
     }
 
     /** LimboSeat is one Limbo player as the flow sees them. */
-    private record LimboSeat(Player player) implements LoginFlow.Seat {
+    private record LimboSeat(Player player, ExperienceConfig experience) implements LoginFlow.Seat {
         @Override
         public String name() {
             return player.getName();
@@ -235,7 +240,9 @@ public final class FelisLimboPlugin extends LimboPlugin implements Listener {
 
         @Override
         public void showCode(LinkCode code, String url) {
-            player.openBook(LoginBook.book(code.code(), url));
+            if (experience.flag("openBook", true)) {
+                player.openBook(LoginBook.book(code.code(), url, experience));
+            }
         }
 
         @Override

plugins/limbo/src/main/java/best/lolicon/felis/limbo/LoginBook.java

@@ -1,5 +1,7 @@
 package best.lolicon.felis.limbo;
 
+import best.lolicon.felis.link.ExperienceConfig;
+import java.util.Map;
 import net.kyori.adventure.inventory.Book;
 import net.kyori.adventure.text.Component;
 import net.kyori.adventure.text.event.ClickEvent;
@@ -30,15 +32,20 @@ final class LoginBook {
     }
 
     static Book book(String code, String url) {
-        Component page = Component.text("Felis 登录 / Login\n\n")
+        return book(code, url, new ExperienceConfig(Map.of()));
+    }
+
+    static Book book(String code, String url, ExperienceConfig settings) {
+        Component page = Component.text(settings.text("bookHeading", "Felis 登录 / Login") + "\n\n")
                 .append(Component.text("绑定码 / Code:\n"))
                 .append(Component.text(code + "\n\n").color(NamedTextColor.GOLD))
-                .append(Component.text("▶ 点此打开登录页\n▶ Open login page\n")
+                .append(Component.text(settings.text("bookAction", "▶ 点此打开登录页\n▶ Open login page") + "\n")
                         .color(NamedTextColor.AQUA)
                         .clickEvent(ClickEvent.openUrl(url)))
-                .append(Component.text("\n在系统浏览器中完成。\nUse your SYSTEM browser —\nnot WeChat / QQ (passkey\nwon't work there).")
+                .append(Component.text("\n" + settings.text("bookHelp", "在系统浏览器中完成。\nUse your SYSTEM browser —\nnot WeChat / QQ (passkey\nwon't work there)."))
                         .color(NamedTextColor.GRAY));
-        return Book.book(Component.text("Felis Login"), Component.text("Felis"), page);
+        return Book.book(Component.text(settings.text("bookTitle", "Felis Login")),
+                Component.text(settings.text("bookAuthor", "Felis")), page);
     }
 
     /** chatLine renders one chat line with § colour codes, its web addresses clickable. */

plugins/limbo/test/best/lolicon/felis/limbo/LoginFlowTest.java

@@ -1,5 +1,6 @@
 package best.lolicon.felis.limbo;
 
+import best.lolicon.felis.link.ExperienceConfig;
 import best.lolicon.felis.link.Control;
 import best.lolicon.felis.link.ControlFrame;
 import best.lolicon.felis.link.FelisApiClient;
@@ -24,6 +25,8 @@ import java.net.http.HttpClient;
 import java.net.http.HttpRequest;
 import java.net.http.HttpResponse;
 import java.nio.charset.StandardCharsets;
+import java.nio.file.Files;
+import java.nio.file.Path;
 import java.util.ArrayList;
 import java.util.HashMap;
 import java.util.List;
@@ -356,7 +359,22 @@ public final class LoginFlowTest {
         assertEq("lobby set", "hub", GateConfig.lobby(" hub "));
     }
 
-    private static void loginBook() {
+    private static void loginBook() throws IOException {
+        Path file = Files.createTempFile("felis-experience", ".json");
+        ExperienceConfig settings;
+        try {
+            Files.writeString(file, "{\"bookTitle\":\"My Network\",\"bookHeading\":\"欢迎 / Welcome\"}");
+            settings = ExperienceConfig.load(file);
+        } finally {
+            Files.deleteIfExists(file);
+        }
+        Book customized = LoginBook.book(CODE, CONSOLE + "/link", settings);
+        assertEq("custom book title", "My Network", plain(customized.title()));
+        assertTrue("custom book reads UTF-8 from the world volume", plain(customized.pages().get(0)).contains("欢迎 / Welcome"));
+        assertEq("custom book keeps the code", true, plain(customized.pages().get(0)).contains(CODE));
+        List<Component> customLinks = new ArrayList<>();
+        collectLinks(customized.pages().get(0), customLinks);
+        assertEq("custom book keeps the generated login URL", CONSOLE + "/link", customLinks.get(0).clickEvent().value());
         Book book = LoginBook.book(CODE, CONSOLE + "/link");
         assertEq("book title", "Felis Login", plain(book.title()));
         Component page = book.pages().get(0);

plugins/paper/build.gradle

@@ -41,7 +41,8 @@ dependencies {
 // plugin-message channel and never holds a felis-api token or talks to felis-api
 // directly. We enforce that physically here — the shared source root is on the
 // path, but the include filter ships ONLY the paper package and the three codec
-// files (Control + ControlFrame + Json). FelisApiClient, LinkClient and the token
+// files (Control + ControlFrame + Json) plus the local ExperienceConfig reader.
+// FelisApiClient, LinkClient and the token
 // config are not compiled in at all, so the lobby cannot reach the API even by
 // mistake. If a codec class grows a new dependency, compilation fails loudly here
 // rather than silently widening the lobby's reach.
@@ -53,6 +54,7 @@ sourceSets {
             include 'best/lolicon/felis/link/Control.java'
             include 'best/lolicon/felis/link/ControlFrame.java'
             include 'best/lolicon/felis/link/Json.java'
+            include 'best/lolicon/felis/link/ExperienceConfig.java'
         }
     }
 }

plugins/paper/src/main/java/best/lolicon/felis/paper/FelisPaperPlugin.java

@@ -2,6 +2,9 @@ package best.lolicon.felis.paper;
 
 import best.lolicon.felis.link.Control;
 import best.lolicon.felis.link.ControlFrame;
+import best.lolicon.felis.link.ExperienceConfig;
+
+import java.io.IOException;
 
 import net.kyori.adventure.text.Component;
 import net.kyori.adventure.text.format.NamedTextColor;
@@ -62,10 +65,16 @@ import java.util.List;
 public final class FelisPaperPlugin extends JavaPlugin {
 
     private LobbyMenu menu;
+    private ExperienceConfig experience;
 
     @Override
     public void onEnable() {
         saveDefaultConfig();
+        try {
+            experience = ExperienceConfig.load(ExperienceConfig.PATH);
+        } catch (IOException e) {
+            throw new IllegalStateException("Cannot load lobby settings", e);
+        }
         if (!getConfig().getStringList("servers").isEmpty()) {
             getLogger().info("config.yml 'servers' is no longer read: the menu lists what the proxy routes.");
         }
@@ -81,7 +90,7 @@ public final class FelisPaperPlugin extends JavaPlugin {
 
         // The lobby is a hub nobody can hurt or be hurt in (LobbyGuard). Worlds loaded
         // before this point get the rules here, later ones on their WorldLoadEvent.
-        LobbyGuard guard = new LobbyGuard(getLogger());
+        LobbyGuard guard = new LobbyGuard(getLogger(), experience);
         getServer().getPluginManager().registerEvents(guard, this);
         getServer().getWorlds().forEach(guard::protect);
 
@@ -125,6 +134,11 @@ public final class FelisPaperPlugin extends JavaPlugin {
             return FelisPaperPlugin.zh(player);
         }
 
+        @Override
+        public String menuTitle() {
+            return experience.text(zh() ? "menuTitleZh" : "menuTitleEn", zh() ? "Felis 服务器" : "Felis Servers");
+        }
+
         @Override
         public boolean online() {
             return player.isOnline();

plugins/paper/src/main/java/best/lolicon/felis/paper/LobbyGuard.java

@@ -1,5 +1,6 @@
 package best.lolicon.felis.paper;
 
+import best.lolicon.felis.link.ExperienceConfig;
 import net.kyori.adventure.text.Component;
 import net.kyori.adventure.text.event.ClickEvent;
 import net.kyori.adventure.text.event.HoverEvent;
@@ -36,6 +37,7 @@ import org.bukkit.event.player.PlayerJoinEvent;
 import org.bukkit.event.vehicle.VehicleDestroyEvent;
 import org.bukkit.event.world.WorldLoadEvent;
 
+import java.util.Map;
 import java.util.logging.Level;
 import java.util.logging.Logger;
 
@@ -45,6 +47,8 @@ import java.util.logging.Logger;
  * Without it the lobby is a plain survival world: mobs at night, PvP, and every block
  * broken or placed by a passer-by stays in the world volume for the next player.
  *
+ * <p>The following are defaults; felis-experience.json can adjust each behavior.
+ *
  * <p><b>World.</b> Every world is made peaceful with natural spawning, PvP, mob
  * griefing and TNT off, time frozen at noon and the weather clear, and inventories
  * kept. These are world rules (level.dat), so they are set here on enable and on
@@ -70,14 +74,20 @@ final class LobbyGuard implements Listener {
     /** Noon: the lobby is always lit. */
     private static final long NOON = 6000L;
 
-    static boolean guarded(Player player) {
-        return !player.hasPermission(BUILD_PERMISSION);
+    boolean guarded(Player player) {
+        return settings.flag("protectBuild", true) && !player.hasPermission(BUILD_PERMISSION);
     }
 
     private final Logger log;
+    private final ExperienceConfig settings;
 
     LobbyGuard(Logger log) {
+        this(log, new ExperienceConfig(Map.of()));
+    }
+
+    LobbyGuard(Logger log, ExperienceConfig settings) {
         this.log = log;
+        this.settings = settings;
     }
 
     /**
@@ -94,25 +104,27 @@ final class LobbyGuard implements Listener {
         }
     }
 
-    static void applyRules(World world) {
-        world.setDifficulty(Difficulty.PEACEFUL);
+    void applyRules(World world) {
+        world.setDifficulty(Difficulty.valueOf(settings.text("difficulty", "PEACEFUL")));
         // Only a world with its own clock has a time of day to set; the nether and the
         // end have none and refuse.
-        if (!world.isFixedTime()) {
-            world.setTime(NOON);
+        if (settings.flag("freezeTime", true) && !world.isFixedTime()) {
+            world.setTime(Math.floorMod(settings.number("time", NOON), 24000L));
         }
-        world.setStorm(false);
-        world.setThundering(false);
-        world.setGameRule(GameRules.PVP, false);
-        world.setGameRule(GameRules.SPAWN_MOBS, false);
-        world.setGameRule(GameRules.SPAWN_WANDERING_TRADERS, false);
-        world.setGameRule(GameRules.MOB_GRIEFING, false);
-        world.setGameRule(GameRules.TNT_EXPLODES, false);
-        world.setGameRule(GameRules.KEEP_INVENTORY, true);
-        world.setGameRule(GameRules.IMMEDIATE_RESPAWN, true);
-        world.setGameRule(GameRules.SHOW_ADVANCEMENT_MESSAGES, false);
-        world.setGameRule(GameRules.ADVANCE_TIME, false);
-        world.setGameRule(GameRules.ADVANCE_WEATHER, false);
+        if (settings.flag("clearWeather", true)) {
+            world.setStorm(false);
+            world.setThundering(false);
+        }
+        world.setGameRule(GameRules.PVP, settings.flag("pvp", false));
+        world.setGameRule(GameRules.SPAWN_MOBS, settings.flag("spawnMobs", false));
+        world.setGameRule(GameRules.SPAWN_WANDERING_TRADERS, settings.flag("spawnMobs", false));
+        world.setGameRule(GameRules.MOB_GRIEFING, settings.flag("mobGriefing", false));
+        world.setGameRule(GameRules.TNT_EXPLODES, settings.flag("tntExplodes", false));
+        world.setGameRule(GameRules.KEEP_INVENTORY, settings.flag("keepInventory", true));
+        world.setGameRule(GameRules.IMMEDIATE_RESPAWN, settings.flag("immediateRespawn", true));
+        world.setGameRule(GameRules.SHOW_ADVANCEMENT_MESSAGES, settings.flag("showAdvancementMessages", false));
+        world.setGameRule(GameRules.ADVANCE_TIME, !settings.flag("freezeTime", true));
+        world.setGameRule(GameRules.ADVANCE_WEATHER, !settings.flag("clearWeather", true));
     }
 
     @EventHandler
@@ -125,20 +137,30 @@ final class LobbyGuard implements Listener {
     @EventHandler
     public void onJoin(PlayerJoinEvent event) {
         Player player = event.getPlayer();
-        player.setFoodLevel(20);
-        if (guarded(player)) {
-            player.setGameMode(GameMode.ADVENTURE);
-            player.teleport(player.getWorld().getSpawnLocation());
+        if (settings.flag("disableHunger", true)) {
+            player.setFoodLevel(20);
+        }
+        if (!player.hasPermission(BUILD_PERMISSION)) {
+            player.setGameMode(GameMode.valueOf(settings.text("gameMode", "ADVENTURE")));
+            if (settings.flag("teleportOnJoin", true)) {
+                player.teleport(player.getWorld().getSpawnLocation());
+            }
+        }
+        if (settings.flag("showWelcome", true)) {
+            player.sendMessage(hint(FelisPaperPlugin.zh(player)));
+        }
+        if (settings.flag("openMenuOnJoin", false)) {
+            player.performCommand("menu");
         }
-        player.sendMessage(hint(FelisPaperPlugin.zh(player)));
     }
 
-    static Component hint(boolean zh) {
+    Component hint(boolean zh) {
         Component open = Component.text(zh ? "[打开服务器菜单]" : "[Open the server menu]",
                         NamedTextColor.GREEN, TextDecoration.BOLD)
                 .clickEvent(ClickEvent.runCommand("/menu"))
                 .hoverEvent(HoverEvent.showText(Component.text(zh ? "点击运行 /menu" : "Click to run /menu")));
-        return Component.text(zh ? "欢迎来到大厅。输入 /menu 或点击 " : "Welcome to the lobby. Type /menu or click ",
+        return Component.text(settings.text(zh ? "welcomeZh" : "welcomeEn",
+                        zh ? "欢迎来到大厅。输入 /menu 或点击 " : "Welcome to the lobby. Type /menu or click "),
                         NamedTextColor.GOLD)
                 .append(open)
                 .append(Component.text(zh ? "，选一个服务器进入。" : " to pick a server to join.",
@@ -152,15 +174,17 @@ final class LobbyGuard implements Listener {
         if (!(event.getEntity() instanceof Player player)) {
             return;
         }
-        event.setCancelled(true);
-        if (event.getCause() == EntityDamageEvent.DamageCause.VOID) {
+        if (settings.flag("invulnerable", true)) {
+            event.setCancelled(true);
+        }
+        if (settings.flag("voidRescue", true) && event.getCause() == EntityDamageEvent.DamageCause.VOID) {
             player.teleport(player.getWorld().getSpawnLocation());
         }
     }
 
     @EventHandler(priority = EventPriority.LOW)
     public void onHunger(FoodLevelChangeEvent event) {
-        if (event.getEntity() instanceof Player) {
+        if (settings.flag("disableHunger", true) && event.getEntity() instanceof Player) {
             event.setCancelled(true);
         }
     }
@@ -211,14 +235,17 @@ final class LobbyGuard implements Listener {
     /** Fire spreads and burns with nobody behind it, so only a builder may start one. */
     @EventHandler(priority = EventPriority.LOW)
     public void onIgnite(BlockIgniteEvent event) {
-        if (!(event.getIgnitingEntity() instanceof Player player) || guarded(player)) {
+        if (settings.flag("protectBuild", true) &&
+                (!(event.getIgnitingEntity() instanceof Player player) || guarded(player))) {
             event.setCancelled(true);
         }
     }
 
     @EventHandler(priority = EventPriority.LOW)
     public void onBurn(BlockBurnEvent event) {
-        event.setCancelled(true);
+        if (settings.flag("protectBuild", true)) {
+            event.setCancelled(true);
+        }
     }
 
     @EventHandler(priority = EventPriority.LOW)
@@ -258,7 +285,7 @@ final class LobbyGuard implements Listener {
     }
 
     /** guardedCulprit: the entity is a guarded player, or something one of them shot. */
-    private static boolean guardedCulprit(Entity culprit) {
+    private boolean guardedCulprit(Entity culprit) {
         if (culprit instanceof Projectile projectile && projectile.getShooter() instanceof Player shooter) {
             return guarded(shooter);
         }

plugins/paper/src/main/java/best/lolicon/felis/paper/LobbyMenu.java

@@ -42,6 +42,10 @@ final class LobbyMenu implements Listener, PluginMessageListener {
         /** zh mirrors the Velocity rule: Chinese when the client locale is zh-*. */
         boolean zh();
 
+        default String menuTitle() {
+            return zh() ? "Felis 服务器" : "Felis Servers";
+        }
+
         boolean online();
 
         void send(ControlFrame frame);
@@ -189,7 +193,7 @@ final class LobbyMenu implements Listener, PluginMessageListener {
                 slots[NEXT_SLOT] = new Nav(true, zh ? "下一页" : "Next page");
             }
         }
-        screen.open(holder, title(zh, p, pages), size, slots);
+        screen.open(holder, title(screen.menuTitle(), p, pages), size, slots);
         // Ask the proxy for live status of every tile on this page; answers repaint them.
         for (String server : view) {
             screen.send(ControlFrame.statusQuery(server));
@@ -286,7 +290,10 @@ final class LobbyMenu implements Listener, PluginMessageListener {
     // ---- text ----
 
     static String title(boolean zh, int page, int pages) {
-        String title = zh ? "Felis 服务器" : "Felis Servers";
+        return title(zh ? "Felis 服务器" : "Felis Servers", page, pages);
+    }
+
+    static String title(String title, int page, int pages) {
         if (pages > 1) {
             title += "  (" + (page + 1) + "/" + pages + ")";
         }

plugins/paper/src/main/resources/config.yml

@@ -4,7 +4,10 @@
 # channel to the Velocity proxy. It holds no felis-api token and never contacts
 # felis-api directly.
 #
-# There is nothing to configure. /menu asks the proxy which servers to show
+# Player-facing settings are edited in the panel at /admin/lobby and stored in
+# /data/felis-experience.json. This file does not hold those settings.
+#
+# /menu asks the proxy which servers to show
 # (a ListRequest over felis:control) and the proxy answers from the same registry
 # it routes by, so a server created in the panel appears here on its own. Tiles are
 # paged 45 at a time. Status, ownership and autostart stay with the proxy and

plugins/paper/test/best/lolicon/felis/paper/LobbyGuardTest.java

@@ -1,6 +1,8 @@
 package best.lolicon.felis.paper;
 
+import best.lolicon.felis.link.ExperienceConfig;
 import best.lolicon.felis.paper.Fakes.FakePlayer;
+import java.util.Map;
 import best.lolicon.felis.paper.Fakes.FakeWorld;
 
 import net.kyori.adventure.text.Component;
@@ -82,6 +84,7 @@ public final class LobbyGuardTest {
         nobodyIsHurt();
         joining();
         worldRules();
+        customization();
         System.out.println("LobbyGuardTest OK (" + checks + " checks)");
     }
 
@@ -196,6 +199,33 @@ public final class LobbyGuardTest {
         assertEq("... with the same click", List.of("/menu"), commands(zh.messages.get(0)));
     }
 
+    private static void customization() {
+        LobbyGuard custom = new LobbyGuard(capturingLogger(), new ExperienceConfig(Map.of(
+                "protectBuild", false, "invulnerable", false, "disableHunger", false,
+                "teleportOnJoin", false, "gameMode", "SURVIVAL", "welcomeEn", "Hello, builders! ",
+                "difficulty", "HARD", "freezeTime", false, "clearWeather", false)));
+        FakePlayer player = new FakePlayer(false, world, Locale.US);
+        custom.onJoin(new PlayerJoinEvent(player.player, Component.text("joined")));
+        assertEq("custom mode", GameMode.SURVIVAL, player.gameMode);
+        assertEq("custom join does not teleport", 0, player.teleports.size());
+        assertEq("hunger remains enabled", 3, player.food);
+        assertEq("custom welcome keeps menu click", List.of("/menu"), commands(player.messages.get(0)));
+        assertEq("custom welcome", true, Fakes.text(player.messages.get(0)).startsWith("Hello, builders!"));
+        BlockBreakEvent build = new BlockBreakEvent(Fakes.block(Material.STONE), player.player);
+        custom.onBreak(build);
+        assertEq("building can be opened", false, build.isCancelled());
+        EntityDamageEvent damage = new EntityDamageEvent(player.player, DamageCause.FALL, HIT, 4);
+        custom.onDamage(damage);
+        assertEq("damage can be enabled", false, damage.isCancelled());
+        FoodLevelChangeEvent hunger = new FoodLevelChangeEvent(player.player, 2);
+        custom.onHunger(hunger);
+        assertEq("hunger can be enabled", false, hunger.isCancelled());
+        FakeWorld natural = new FakeWorld();
+        custom.protect(natural.world);
+        assertEq("custom difficulty, advancing time and weather", List.of("setDifficulty HARD"), natural.calls);
+        assertEq("custom menu keeps pagination", "My Hub  (2/3)", LobbyMenu.title("My Hub", 1, 3));
+    }
+
     private static void worldRules() {
         FakeWorld overworld = new FakeWorld("world", false, false);
         WARNINGS.clear();

plugins/shared/src/main/java/best/lolicon/felis/link/ExperienceConfig.java

@@ -0,0 +1,43 @@
+package best.lolicon.felis.link;
+
+import java.io.IOException;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.util.Map;
+
+/** Player-facing settings on the persistent world volume, edited by the panel. */
+public final class ExperienceConfig {
+    public static final Path PATH = Path.of("felis-experience.json");
+    private final Map<?, ?> values;
+
+    public ExperienceConfig(Map<?, ?> values) {
+        this.values = values;
+    }
+
+    public static ExperienceConfig load(Path path) throws IOException {
+        if (!Files.exists(path)) {
+            return new ExperienceConfig(Map.of());
+        }
+        try {
+            Object value = Json.parse(Files.readString(path));
+            if (value instanceof Map<?, ?> map) {
+                return new ExperienceConfig(map);
+            }
+            throw new IllegalArgumentException("expected an object");
+        } catch (IllegalArgumentException e) {
+            throw new IOException("invalid " + path + ": " + e.getMessage(), e);
+        }
+    }
+
+    public String text(String key, String fallback) {
+        return values.get(key) instanceof String value ? value : fallback;
+    }
+
+    public boolean flag(String key, boolean fallback) {
+        return values.get(key) instanceof Boolean value ? value : fallback;
+    }
+
+    public long number(String key, long fallback) {
+        return values.get(key) instanceof Number value ? value.longValue() : fallback;
+    }
+}