feat(backend): per-tier, per-kind active-game limits with a guest funnel

Cap a player's simultaneous unfinished games per kind (vs_ai, random,
friends) with independent guest and durable-account tiers, held in a new
single-row backend.config table (-1 = unlimited) behind an in-memory cache
and editable live in the admin console (/_gm/limits). Each game is tagged
with games.game_kind on creation.

This replaces the earlier flat MaxActiveQuickGames=10 combined cap: the
per-tier/kind config is the single mechanism, enforced at the same handler
gate (ensureUnderGameLimit by kind on lobby/enqueue) plus the durable
friends cap in CreateInvitation. game.Service.AtGameLimit only resolves the
tier and counts; the limit policy stays at the request edge.

Guests are now refused friend requests, friend-code redemption,
befriend-in-game and invitation creation outright (403 guest_forbidden) --
previously only the UI hid these.

Admin: a kind column in both game lists and the config editor.

Defaults: guest 1 vs_ai / 1 random / 0 friends; durable 10 / 10 / 10.

backend/internal/adminconsole/templates/layout.gohtml

@@ -15,6 +15,7 @@
     <a href="/_gm/"{{if eq .ActiveNav "dashboard"}} class="active"{{end}}>Dashboard</a>
     <a href="/_gm/users"{{if eq .ActiveNav "users"}} class="active"{{end}}>Users</a>
     <a href="/_gm/games"{{if eq .ActiveNav "games"}} class="active"{{end}}>Games</a>
+    <a href="/_gm/limits"{{if eq .ActiveNav "limits"}} class="active"{{end}}>Limits</a>
     <a href="/_gm/complaints"{{if eq .ActiveNav "complaints"}} class="active"{{end}}>Complaints</a>
     <a href="/_gm/feedback"{{if eq .ActiveNav "feedback"}} class="active"{{end}}>Feedback</a>
     <a href="/_gm/messages"{{if eq .ActiveNav "messages"}} class="active"{{end}}>Messages</a>

backend/internal/adminconsole/templates/pages/games.gohtml

@@ -8,11 +8,11 @@
 <a href="/_gm/games?status=finished"{{if eq .Status "finished"}} class="active"{{end}}>finished</a>
 </nav>
 <table class="list">
-<thead><tr><th>Game</th><th>Variant</th><th>Status</th><th>🤖</th><th class="num">Players</th><th>Updated</th></tr></thead>
+<thead><tr><th>Game</th><th>Variant</th><th>Kind</th><th>Status</th><th>🤖</th><th class="num">Players</th><th>Updated</th></tr></thead>
 <tbody>
 {{range .Items}}
-<tr><td><a href="/_gm/games/{{.ID}}">{{.ID}}</a></td><td>{{.Variant}}</td><td>{{.Status}}</td><td>{{if .VsAI}}🤖{{end}}</td><td class="num">{{.Players}}</td><td>{{.UpdatedAt}}</td></tr>
-{{else}}<tr><td colspan="6"><span class="note">no games</span></td></tr>{{end}}
+<tr><td><a href="/_gm/games/{{.ID}}">{{.ID}}</a></td><td>{{.Variant}}</td><td>{{.Kind}}</td><td>{{.Status}}</td><td>{{if .VsAI}}🤖{{end}}</td><td class="num">{{.Players}}</td><td>{{.UpdatedAt}}</td></tr>
+{{else}}<tr><td colspan="7"><span class="note">no games</span></td></tr>{{end}}
 </tbody>
 </table>
 <nav class="pager">

backend/internal/adminconsole/templates/pages/limits.gohtml

@@ -0,0 +1,19 @@
+{{define "content" -}}
+<h1>Active-game limits</h1>
+{{with .Data}}
+<p class="note">Per-tier, per-kind caps on a player's simultaneous unfinished games. <strong>-1</strong> = unlimited, <strong>0</strong> = the kind is blocked, a positive number caps concurrent games of that kind. Guests are additionally blocked from friend games outright. Changes apply immediately (no redeploy); games already in progress are never affected.</p>
+<section class="panel">
+<form class="form col" method="post" action="/_gm/limits">
+<h2>Guest</h2>
+<label>vs AI <input type="number" name="guest_vs_ai" min="-1" value="{{.GuestVsAI}}" required></label>
+<label>Random <input type="number" name="guest_random" min="-1" value="{{.GuestRandom}}" required></label>
+<label>Friends <input type="number" name="guest_friends" min="-1" value="{{.GuestFriends}}" required></label>
+<h2>Durable account</h2>
+<label>vs AI <input type="number" name="durable_vs_ai" min="-1" value="{{.DurableVsAI}}" required></label>
+<label>Random <input type="number" name="durable_random" min="-1" value="{{.DurableRandom}}" required></label>
+<label>Friends <input type="number" name="durable_friends" min="-1" value="{{.DurableFriends}}" required></label>
+<div><button type="submit">Save</button></div>
+</form>
+</section>
+{{end}}
+{{- end}}

backend/internal/adminconsole/templates/pages/user_detail.gohtml

@@ -211,11 +211,11 @@
 {{end}}
 <section class="panel"><h2>Games</h2>
 <table class="list">
-<thead><tr><th>Game</th><th>Variant</th><th>Status</th><th class="num">Players</th><th>Updated</th></tr></thead>
+<thead><tr><th>Game</th><th>Variant</th><th>Kind</th><th>Status</th><th class="num">Players</th><th>Updated</th></tr></thead>
 <tbody>
 {{range .Games}}
-<tr><td><a href="/_gm/games/{{.ID}}">{{.ID}}</a></td><td>{{.Variant}}</td><td>{{.Status}}</td><td class="num">{{.Players}}</td><td>{{.UpdatedAt}}</td></tr>
-{{else}}<tr><td colspan="5"><span class="note">no games</span></td></tr>{{end}}
+<tr><td><a href="/_gm/games/{{.ID}}">{{.ID}}</a></td><td>{{.Variant}}</td><td>{{.Kind}}</td><td>{{.Status}}</td><td class="num">{{.Players}}</td><td>{{.UpdatedAt}}</td></tr>
+{{else}}<tr><td colspan="6"><span class="note">no games</span></td></tr>{{end}}
 </tbody>
 </table>
 </section>

backend/internal/adminconsole/views.go

@@ -312,6 +312,8 @@ type GameRow struct {
 	UpdatedAt string
 	// VsAI marks an honest-AI game (rendered as 🤖 in the list's AI column).
 	VsAI bool
+	// Kind is the game's origin tag label: vs_ai / random / friends / unknown.
+	Kind string
 }
 
 // GamesView is the paginated games list, optionally filtered by status.
@@ -321,6 +323,17 @@ type GamesView struct {
 	Pager  Pager
 }
 
+// GameLimitsView is the per-tier, per-kind active-game limit form: each field is a cap where -1
+// is unlimited, 0 blocks the kind, and a positive value caps concurrent games of that kind.
+type GameLimitsView struct {
+	GuestVsAI      int
+	GuestRandom    int
+	GuestFriends   int
+	DurableVsAI    int
+	DurableRandom  int
+	DurableFriends int
+}
+
 // GameDetailView is one game with its seats.
 type GameDetailView struct {
 	ID          string

backend/internal/game/service.go

@@ -17,6 +17,7 @@ import (
 
 	"scrabble/backend/internal/account"
 	"scrabble/backend/internal/engine"
+	"scrabble/backend/internal/gamelimits"
 	"scrabble/backend/internal/notify"
 	"scrabble/backend/internal/payments"
 	"scrabble/backend/internal/session"
@@ -57,6 +58,9 @@ type Service struct {
 	// nil, only the free per-game allowance is served (no purchased hints). vs_ai hints are
 	// wallet-free and never touch it.
 	hintWallet HintWallet
+	// limits is the per-tier active-game cap config (cached). Set by SetGameLimits during wiring;
+	// when nil, no active-game limit is enforced (a game is always creatable).
+	limits *gamelimits.Service
 	// clearNudges, when set, marks the actor's pending nudges in a game read once they
 	// have committed a move (a nudge answered by moving stops counting as unread). It is
 	// best-effort and kept as a func so the game package never imports the social package.
@@ -126,6 +130,37 @@ func (svc *Service) SetHintWallet(w HintWallet) {
 	svc.hintWallet = w
 }
 
+// SetGameLimits installs the active-game limit config (cached), enabling the per-tier caps. When
+// unset (nil), a game is always creatable.
+func (svc *Service) SetGameLimits(l *gamelimits.Service) {
+	svc.limits = l
+}
+
+// AtGameLimit reports whether accountID has reached its tier's active-game cap for kind — the
+// per-tier, per-kind limits held in backend.config, read from the in-memory cache. It resolves
+// the caller's tier (guest vs durable) from the account, then counts its open+active games of that
+// kind. It reports false (not at the limit) when the limits config is not wired, the account is nil,
+// or the resolved cap is gamelimits.Unlimited. It backs the new-game gate (the handler aborts 409
+// game_limit_reached) and the lobby's at-limit flag.
+func (svc *Service) AtGameLimit(ctx context.Context, accountID uuid.UUID, kind gamelimits.Kind) (bool, error) {
+	if svc.limits == nil || accountID == uuid.Nil {
+		return false, nil
+	}
+	acc, err := svc.accounts.GetByID(ctx, accountID)
+	if err != nil {
+		return false, err
+	}
+	limit := svc.limits.LimitsFor(acc.IsGuest).Cap(kind)
+	if limit == gamelimits.Unlimited {
+		return false, nil
+	}
+	n, err := svc.store.CountActiveByKind(ctx, accountID, kind)
+	if err != nil {
+		return false, err
+	}
+	return n >= limit, nil
+}
+
 // walletContext resolves the payments gate inputs for an account on the current request: the
 // trusted execution context (from the session platform carried on ctx; absent ⇒ untrusted) and
 // the account's present identity sources (which chip/benefit segments are awake, §6).
@@ -338,6 +373,7 @@ func (svc *Service) Create(ctx context.Context, params CreateParams) (Game, erro
 		dropoutTiles:         params.DropoutTiles.String(),
 		multipleWordsPerTurn: params.MultipleWordsPerTurn,
 		vsAI:                 params.VsAI,
+		kind:                 params.Kind,
 	}
 	if err := svc.store.CreateGame(ctx, ins, seats, seeding.draws); err != nil {
 		return Game{}, err
@@ -401,6 +437,7 @@ func (svc *Service) OpenOrJoin(ctx context.Context, accountID uuid.UUID, params
 		multipleWordsPerTurn: params.MultipleWordsPerTurn,
 		status:               StatusOpen,
 		openDeadline:         &deadline,
+		kind:                 gamelimits.KindRandom,
 	}
 	// Decide the first move now by the official draw, with the not-yet-arrived opponent as a
 	// synthetic placeholder (uuid.Nil): the draw fixes who sits at seat 0 — and so moves
@@ -1386,14 +1423,6 @@ func (svc *Service) ListForLobby(ctx context.Context, accountID uuid.UUID) ([]Ga
 	return kept, nil
 }
 
-// CountActiveQuickGames reports how many in-progress quick games the account holds —
-// the count the simultaneous-game limit (MaxActiveQuickGames) is checked against. It
-// counts active and still-open quick games (including honest-AI ones) and excludes
-// friend games created by invitation and finished games. See Store.CountActiveQuickGames.
-func (svc *Service) CountActiveQuickGames(ctx context.Context, accountID uuid.UUID) (int, error) {
-	return svc.store.CountActiveQuickGames(ctx, accountID)
-}
-
 // HideGame hides a finished game from accountID's own lobby (it stays visible to the other
 // players); it is irreversible by design. Only a player of a finished game may hide it
 // (ErrNotAPlayer / ErrGameActive otherwise); hiding an already-hidden game is a no-op.

backend/internal/game/store.go

@@ -15,6 +15,7 @@ import (
 
 	"scrabble/backend/internal/account"
 	"scrabble/backend/internal/engine"
+	"scrabble/backend/internal/gamelimits"
 	"scrabble/backend/internal/postgres/jet/backend/model"
 	"scrabble/backend/internal/postgres/jet/backend/table"
 )
@@ -45,6 +46,8 @@ type gameInsert struct {
 	multipleWordsPerTurn bool
 	// vsAI marks an honest-AI game (games.vs_ai).
 	vsAI bool
+	// kind tags the game's origin (games.game_kind) for the active-game limits.
+	kind gamelimits.Kind
 	// status is the lifecycle state to create the game in: StatusActive for a normal
 	// seated game, StatusOpen for an auto-match game still awaiting an opponent. An
 	// empty string defaults to StatusActive.
@@ -138,6 +141,20 @@ func (s *Store) CreateGame(ctx context.Context, ins gameInsert, seats []seatInse
 	})
 }
 
+// CountActiveByKind counts the account's active (open or in-progress) games of the given kind — the
+// per-tier active-game limit is checked against it before a new game of that kind is created.
+func (s *Store) CountActiveByKind(ctx context.Context, accountID uuid.UUID, kind gamelimits.Kind) (int, error) {
+	var n int
+	if err := s.db.QueryRowContext(ctx,
+		`SELECT count(*) FROM backend.games g
+		   JOIN backend.game_players p ON p.game_id = g.game_id
+		  WHERE p.account_id = $1 AND g.game_kind = $2 AND g.status IN ('open', 'active')`,
+		accountID, int16(kind)).Scan(&n); err != nil {
+		return 0, fmt.Errorf("game: count active by kind %s: %w", accountID, err)
+	}
+	return n, nil
+}
+
 // insertGameTx inserts the games row and one game_players row per seat (seat 0
 // first) on tx, stamping each seat's display-name snapshot. A seat whose account id is
 // uuid.Nil is written with a NULL account_id (and an empty snapshot) — the still-empty
@@ -155,9 +172,9 @@ func insertGameTx(ctx context.Context, tx *sql.Tx, ins gameInsert, seats []seatI
 		table.Games.GameID, table.Games.Variant, table.Games.DictVersion, table.Games.Seed,
 		table.Games.Status, table.Games.Players, table.Games.TurnTimeoutSecs,
 		table.Games.HintsAllowed, table.Games.HintsPerPlayer, table.Games.OpenDeadlineAt,
-		table.Games.DropoutTiles, table.Games.MultipleWordsPerTurn, table.Games.VsAi,
+		table.Games.DropoutTiles, table.Games.MultipleWordsPerTurn, table.Games.VsAi, table.Games.GameKind,
 	).VALUES(ins.id, ins.variant, ins.dictVersion, ins.seed, status, ins.players,
-		ins.turnTimeoutSecs, ins.hintsAllowed, ins.hintsPerPlayer, deadline, ins.dropoutTiles, ins.multipleWordsPerTurn, ins.vsAI)
+		ins.turnTimeoutSecs, ins.hintsAllowed, ins.hintsPerPlayer, deadline, ins.dropoutTiles, ins.multipleWordsPerTurn, ins.vsAI, int16(ins.kind))
 	if _, err := gi.ExecContext(ctx, tx); err != nil {
 		return fmt.Errorf("insert game: %w", err)
 	}
@@ -501,28 +518,6 @@ func (s *Store) ListGamesForAccount(ctx context.Context, accountID uuid.UUID) ([
 	return out, nil
 }
 
-// CountActiveQuickGames counts the account's in-progress quick games — the ones the
-// simultaneous-game limit (MaxActiveQuickGames) is checked against. It includes both
-// active and still-open (awaiting-opponent) games, the honest-AI ones among them, and
-// excludes friend games (those linked to a game_invitations row) and finished games.
-// A hidden game still occupies a slot, so this is a dedicated count rather than a
-// filter over ListGamesForAccount (which drops hidden games). Joining on the account's
-// own seat counts each game once (an open game's empty opponent seat has no account).
-func (s *Store) CountActiveQuickGames(ctx context.Context, accountID uuid.UUID) (int, error) {
-	// The status literals are game.StatusActive / game.StatusOpen, matching the
-	// games.status CHECK in the baseline migration.
-	const q = `
-SELECT COUNT(*) FROM backend.games g
-JOIN backend.game_players gp ON gp.game_id = g.game_id
-LEFT JOIN backend.game_invitations gi ON gi.game_id = g.game_id
-WHERE gp.account_id = $1 AND g.status IN ('active', 'open') AND gi.game_id IS NULL`
-	var n int
-	if err := s.db.QueryRowContext(ctx, q, accountID).Scan(&n); err != nil {
-		return 0, fmt.Errorf("game: count active quick games: %w", err)
-	}
-	return n, nil
-}
-
 // HideGame hides a game from the account's own lobby list (idempotent). The caller validates the
 // game is finished and the account is a player.
 func (s *Store) HideGame(ctx context.Context, accountID, gameID uuid.UUID) error {
@@ -1361,6 +1356,7 @@ func projectGame(g model.Games, seats []model.GamePlayers) (Game, error) {
 	}
 	out.MultipleWordsPerTurn = g.MultipleWordsPerTurn
 	out.VsAI = g.VsAi
+	out.Kind = gamelimits.Kind(g.GameKind)
 	if g.EndReason != nil {
 		out.EndReason = *g.EndReason
 	}

backend/internal/game/types.go

@@ -7,6 +7,7 @@ import (
 	"github.com/google/uuid"
 
 	"scrabble/backend/internal/engine"
+	"scrabble/backend/internal/gamelimits"
 )
 
 // Status values persisted in the games.status column.
@@ -94,15 +95,6 @@ const DefaultTurnTimeout = 24 * time.Hour
 // one of AllowedTurnTimeouts (never offered in the creation UI).
 const AIInactivityTimeout = 7 * 24 * time.Hour
 
-// MaxActiveQuickGames is the cap on a player's simultaneous quick games (human
-// auto-match and honest-AI), counting both in-progress (StatusActive) and
-// still-open, awaiting-opponent (StatusOpen) games. Friend games created by
-// invitation are not counted. At the cap the backend refuses to create a new game
-// of any kind — quick or by invitation — and the lobby disables "New Game";
-// accepting an incoming invitation is always allowed. See
-// Store.CountActiveQuickGames.
-const MaxActiveQuickGames = 10
-
 // aiPlayerName labels the robot seat in an honest-AI game's GCG export, so a downloaded
 // game file shows a clean "AI" rather than the robot's human-like pool name (the in-app
 // UI shows 🤖 from the game's vs_ai flag).
@@ -125,6 +117,10 @@ type CreateParams struct {
 	// robot is seated at once, the move clock is AIInactivityTimeout, and chat/nudge
 	// and finish-time statistics are suppressed. Set by the lobby's AI-match path.
 	VsAI bool
+	// Kind tags the game's origin (games.game_kind) for the active-game limits: vs_ai / random /
+	// friends. The lobby sets it; a zero (unknown) kind is never gated. The active-game limit itself
+	// is enforced at the new-game handler (Server.ensureUnderGameLimit), not here.
+	Kind gamelimits.Kind
 }
 
 // Game is the persisted state of a match: the games row joined with its seats.
@@ -151,6 +147,9 @@ type Game struct {
 	// VsAI is true for an honest-AI game (games.vs_ai): the opponent is a robot the
 	// player knowingly chose, shown as 🤖, with chat/nudge disabled and no statistics.
 	VsAI bool
+	// Kind is the game's origin tag (games.game_kind) for the active-game limits: vs_ai / random /
+	// friends, or unknown for an untagged game. Read-only projection; set once on creation.
+	Kind gamelimits.Kind
 }
 
 // Seat is one player's standing in a game.

backend/internal/gamelimits/gamelimits.go

@@ -0,0 +1,149 @@
+// Package gamelimits holds the per-tier, per-kind active-game caps (a guest funnel) with a hot
+// in-memory cache over the single-row backend.config, so a login or a game-create never queries it.
+package gamelimits
+
+import (
+	"context"
+	"database/sql"
+	"fmt"
+	"sync"
+
+	"github.com/go-jet/jet/v2/postgres"
+
+	"scrabble/backend/internal/postgres/jet/backend/model"
+	"scrabble/backend/internal/postgres/jet/backend/table"
+)
+
+// Kind is a game's kind, mirroring backend.games.game_kind. 0 (unknown) is an untagged game, never gated.
+type Kind int16
+
+const (
+	KindUnknown Kind = 0
+	KindVsAI    Kind = 1
+	KindRandom  Kind = 2
+	KindFriends Kind = 3
+)
+
+// String returns the kind's label for admin game lists and logs.
+func (k Kind) String() string {
+	switch k {
+	case KindVsAI:
+		return "vs_ai"
+	case KindRandom:
+		return "random"
+	case KindFriends:
+		return "friends"
+	default:
+		return "unknown"
+	}
+}
+
+// Unlimited is the limit sentinel meaning no cap.
+const Unlimited = -1
+
+// Limits is a tier's active-game caps per kind (-1 = unlimited).
+type Limits struct {
+	VsAI    int
+	Random  int
+	Friends int
+}
+
+// Cap returns the limit for kind; the unknown kind is never capped.
+func (l Limits) Cap(kind Kind) int {
+	switch kind {
+	case KindVsAI:
+		return l.VsAI
+	case KindRandom:
+		return l.Random
+	case KindFriends:
+		return l.Friends
+	default:
+		return Unlimited
+	}
+}
+
+// Config is the per-tier limit config (the single backend.config row).
+type Config struct {
+	Guest   Limits
+	Durable Limits
+}
+
+// Store reads and writes the single-row backend.config.
+type Store struct{ db *sql.DB }
+
+// NewStore constructs a Store over db.
+func NewStore(db *sql.DB) *Store { return &Store{db: db} }
+
+func (s *Store) load(ctx context.Context) (Config, error) {
+	var c model.Config
+	if err := postgres.SELECT(table.Config.AllColumns).FROM(table.Config).LIMIT(1).
+		QueryContext(ctx, s.db, &c); err != nil {
+		return Config{}, fmt.Errorf("gamelimits: load config: %w", err)
+	}
+	return Config{
+		Guest:   Limits{VsAI: int(c.GuestVsAiLimit), Random: int(c.GuestRandomLimit), Friends: int(c.GuestFriendsLimit)},
+		Durable: Limits{VsAI: int(c.DurableVsAiLimit), Random: int(c.DurableRandomLimit), Friends: int(c.DurableFriendsLimit)},
+	}, nil
+}
+
+func (s *Store) save(ctx context.Context, c Config) error {
+	if _, err := s.db.ExecContext(ctx,
+		`UPDATE backend.config SET guest_vs_ai_limit=$1, guest_random_limit=$2, guest_friends_limit=$3,
+		   durable_vs_ai_limit=$4, durable_random_limit=$5, durable_friends_limit=$6 WHERE only_row`,
+		c.Guest.VsAI, c.Guest.Random, c.Guest.Friends, c.Durable.VsAI, c.Durable.Random, c.Durable.Friends); err != nil {
+		return fmt.Errorf("gamelimits: save config: %w", err)
+	}
+	return nil
+}
+
+// Service fronts the config with an in-memory cache (single-instance, matching the deploy). Load
+// once at startup; Update after an admin edit refreshes it in place.
+type Service struct {
+	store *Store
+	mu    sync.RWMutex
+	cfg   Config
+}
+
+// NewService constructs a Service over store. Call Load before serving.
+func NewService(store *Store) *Service { return &Service{store: store} }
+
+// Load reads the config into the cache. Call once at startup.
+func (s *Service) Load(ctx context.Context) error {
+	c, err := s.store.load(ctx)
+	if err != nil {
+		return err
+	}
+	s.set(c)
+	return nil
+}
+
+func (s *Service) set(c Config) {
+	s.mu.Lock()
+	s.cfg = c
+	s.mu.Unlock()
+}
+
+// Get returns the cached config.
+func (s *Service) Get() Config {
+	s.mu.RLock()
+	defer s.mu.RUnlock()
+	return s.cfg
+}
+
+// LimitsFor returns the cached limits for the account tier (guest or durable).
+func (s *Service) LimitsFor(isGuest bool) Limits {
+	c := s.Get()
+	if isGuest {
+		return c.Guest
+	}
+	return c.Durable
+}
+
+// Update saves the config and refreshes the cache in place (the admin edit).
+func (s *Service) Update(ctx context.Context, c Config) error {
+	if err := s.store.save(ctx, c); err != nil {
+		return err
+	}
+	s.set(c)
+	return nil
+}

backend/internal/gamelimits/gamelimits_test.go

@@ -0,0 +1,44 @@
+package gamelimits
+
+import "testing"
+
+// TestLimitsCap checks Cap maps each kind to its field and leaves the unknown kind uncapped, so a
+// untagged game (game_kind 0) is never gated.
+func TestLimitsCap(t *testing.T) {
+	l := Limits{VsAI: 1, Random: 2, Friends: 3}
+	for _, tc := range []struct {
+		kind Kind
+		want int
+	}{
+		{KindVsAI, 1},
+		{KindRandom, 2},
+		{KindFriends, 3},
+		{KindUnknown, Unlimited},
+		{Kind(99), Unlimited},
+	} {
+		if got := l.Cap(tc.kind); got != tc.want {
+			t.Errorf("Cap(%d) = %d, want %d", tc.kind, got, tc.want)
+		}
+	}
+}
+
+// TestServiceLimitsForTier checks LimitsFor selects the guest or durable tier from the cached config.
+func TestServiceLimitsForTier(t *testing.T) {
+	svc := NewService(nil)
+	svc.set(Config{
+		Guest:   Limits{VsAI: 1, Random: 1, Friends: 0},
+		Durable: Limits{VsAI: 10, Random: 10, Friends: 10},
+	})
+
+	if got := svc.LimitsFor(true); got != (Limits{VsAI: 1, Random: 1, Friends: 0}) {
+		t.Errorf("guest limits = %+v, want {1 1 0}", got)
+	}
+	if got := svc.LimitsFor(false); got != (Limits{VsAI: 10, Random: 10, Friends: 10}) {
+		t.Errorf("durable limits = %+v, want {10 10 10}", got)
+	}
+	// The unlimited sentinel resolves through the tier too.
+	svc.set(Config{Durable: Limits{VsAI: Unlimited, Random: Unlimited, Friends: Unlimited}})
+	if got := svc.LimitsFor(false).Cap(KindVsAI); got != Unlimited {
+		t.Errorf("durable vs_ai cap = %d, want unlimited (-1)", got)
+	}
+}

backend/internal/inttest/game_limit_test.go

@@ -5,6 +5,7 @@ package inttest
 import (
 	"context"
 	"encoding/json"
+	"errors"
 	"fmt"
 	"net/http"
 	"net/http/httptest"
@@ -18,59 +19,119 @@ import (
 	"scrabble/backend/internal/account"
 	"scrabble/backend/internal/engine"
 	"scrabble/backend/internal/game"
+	"scrabble/backend/internal/gamelimits"
+	"scrabble/backend/internal/lobby"
 	"scrabble/backend/internal/server"
+	"scrabble/backend/internal/social"
 )
 
-// The game-limit suite covers the simultaneous quick-game cap (game.MaxActiveQuickGames):
-// the counting rule (Store/Service.CountActiveQuickGames) and the HTTP gate that refuses a
-// new game once the cap is reached, while accepting an incoming invitation stays allowed.
+// The game-limit suite covers the per-tier, per-kind active-game caps (backend.config): the
+// game_kind tag persisted per creation path, the tier resolution + counting rule
+// (game.Service.AtGameLimit), the HTTP gate + lobby at_game_limit flag, the guest gate on friend
+// actions, and the config hot-cache reflecting an admin edit. Accepting an invitation stays exempt.
 
-// TestCountActiveQuickGames checks the count includes active and open quick games (the
-// honest-AI ones among them) and excludes finished games, friend games (created by
-// invitation) and games the account is not seated in.
-func TestCountActiveQuickGames(t *testing.T) {
+// newGameLimits builds a gamelimits service over the shared pool and loads the seeded config
+// (guest 1/1/0, durable 10/10/10).
+func newGameLimits(t *testing.T) *gamelimits.Service {
+	t.Helper()
+	gl := gamelimits.NewService(gamelimits.NewStore(testDB))
+	if err := gl.Load(context.Background()); err != nil {
+		t.Fatalf("load game limits: %v", err)
+	}
+	return gl
+}
+
+// restoreDefaultLimits resets the single config row to the migration seed on cleanup, so a test that
+// edited it never leaks its values into another (the row is a shared singleton).
+func restoreDefaultLimits(t *testing.T, gl *gamelimits.Service) {
+	t.Helper()
+	t.Cleanup(func() {
+		_ = gl.Update(context.Background(), gamelimits.Config{
+			Guest:   gamelimits.Limits{VsAI: 1, Random: 1, Friends: 0},
+			Durable: gamelimits.Limits{VsAI: 10, Random: 10, Friends: 10},
+		})
+	})
+}
+
+// gameKind reads a game's persisted game_kind tag.
+func gameKind(t *testing.T, gameID uuid.UUID) int16 {
+	t.Helper()
+	var k int16
+	if err := testDB.QueryRowContext(context.Background(),
+		`SELECT game_kind FROM backend.games WHERE game_id=$1`, gameID).Scan(&k); err != nil {
+		t.Fatalf("read game_kind: %v", err)
+	}
+	return k
+}
+
+// mustCreateKind creates an active game seating the accounts, tagged with kind, and returns its id.
+func mustCreateKind(t *testing.T, games *game.Service, seats []uuid.UUID, kind gamelimits.Kind) uuid.UUID {
+	t.Helper()
+	g, err := games.Create(context.Background(), game.CreateParams{
+		Variant: engine.VariantEnglish, Seats: seats, TurnTimeout: 24 * time.Hour, Kind: kind,
+	})
+	if err != nil {
+		t.Fatalf("create game (kind=%d): %v", kind, err)
+	}
+	return g.ID
+}
+
+// startFriendGameID has inviter invite invitee to a friend game and the invitee accept, returning
+// the started game's id.
+func startFriendGameID(t *testing.T, inv *lobby.InvitationService, inviter, invitee uuid.UUID) uuid.UUID {
+	t.Helper()
+	ctx := context.Background()
+	invitation, err := inv.CreateInvitation(ctx, inviter, []uuid.UUID{invitee}, englishInvite())
+	if err != nil {
+		t.Fatalf("create invitation: %v", err)
+	}
+	got, err := inv.RespondInvitation(ctx, invitation.ID, invitee, true)
+	if err != nil {
+		t.Fatalf("accept invitation: %v", err)
+	}
+	if got.GameID == nil {
+		t.Fatal("accepted invitation has no game id")
+	}
+	return *got.GameID
+}
+
+// TestGameKindPersisted checks each creation path stamps the right game_kind: random (auto-match)
+// =2, vs_ai =1, friend (by invitation) =3.
+func TestGameKindPersisted(t *testing.T) {
 	ctx := context.Background()
 	clearOpenGames(t)
 	games := newGameService()
-	human := provisionAccount(t)
-	opp := provisionAccount(t)
+	inv := newInvitationService()
+	human, opp := provisionAccount(t), provisionAccount(t)
 
-	if n := mustCount(t, games, human); n != 0 {
-		t.Fatalf("fresh account count = %d, want 0", n)
+	rnd, _, err := games.OpenOrJoin(ctx, human, game.CreateParams{Variant: engine.VariantEnglish, TurnTimeout: 24 * time.Hour}, time.Now().Add(time.Minute), nil)
+	if err != nil {
+		t.Fatalf("open random game: %v", err)
+	}
+	if k := gameKind(t, rnd.ID); k != int16(gamelimits.KindRandom) {
+		t.Errorf("random game_kind = %d, want %d", k, gamelimits.KindRandom)
 	}
 
-	// An open (awaiting-opponent) quick game counts.
-	if _, _, err := games.OpenOrJoin(ctx, human, game.CreateParams{
-		Variant: engine.VariantEnglish, TurnTimeout: 24 * time.Hour,
-	}, time.Now().Add(time.Minute), nil); err != nil {
-		t.Fatalf("open quick game: %v", err)
+	ai := mustCreateKind(t, games, []uuid.UUID{human, opp}, gamelimits.KindVsAI)
+	if k := gameKind(t, ai); k != int16(gamelimits.KindVsAI) {
+		t.Errorf("vs_ai game_kind = %d, want %d", k, gamelimits.KindVsAI)
 	}
-	// An active quick game and an honest-AI quick game both count (neither has an invitation row).
-	mustCreateQuick(t, games, []uuid.UUID{human, opp}, false, 1)
-	mustCreateQuick(t, games, []uuid.UUID{human, opp}, true, 2)
 
-	// A finished quick game does NOT count.
-	fin := mustCreateQuick(t, games, []uuid.UUID{human, opp}, false, 3)
-	if _, err := testDB.ExecContext(ctx, `UPDATE backend.games SET status='finished' WHERE game_id=$1`, fin); err != nil {
-		t.Fatalf("finish game: %v", err)
-	}
-	// A game the human is not seated in does NOT count.
-	mustCreateQuick(t, games, []uuid.UUID{opp, provisionAccount(t)}, false, 4)
-	// A friend game (created by invitation) does NOT count, even though it is active.
-	startFriendGame(t, human)
-
-	if n := mustCount(t, games, human); n != 3 {
-		t.Fatalf("active quick count = %d, want 3 (active + AI + open)", n)
+	friend := startFriendGameID(t, inv, human, opp)
+	if k := gameKind(t, friend); k != int16(gamelimits.KindFriends) {
+		t.Errorf("friend game_kind = %d, want %d", k, gamelimits.KindFriends)
 	}
 }
 
-// TestGameLimitGate drives the cap through the assembled HTTP server: under the cap the lobby
-// reports at_game_limit false; at the cap it flips to true and both new-game endpoints (quick
-// enqueue and invitation creation) are refused with 409 game_limit_reached, while accepting an
-// incoming invitation is still allowed.
-func TestGameLimitGate(t *testing.T) {
+// TestGuestActiveGameLimitHTTP drives the guest random cap through the assembled server: the first
+// auto-match opens a game, the lobby then flags at_game_limit, and a second enqueue is refused 409
+// game_limit_reached. It also checks the guest vs_ai and friends caps resolve at the domain level.
+func TestGuestActiveGameLimitHTTP(t *testing.T) {
 	ctx := context.Background()
+	clearOpenGames(t)
+	gl := newGameLimits(t)
 	games := newGameService()
+	games.SetGameLimits(gl)
 	srv := server.New(":0", server.Deps{
 		Logger:      zaptest.NewLogger(t),
 		DB:          testDB,
@@ -78,88 +139,110 @@ func TestGameLimitGate(t *testing.T) {
 		Games:       games,
 		Matchmaker:  newMatchmaker(t, newRobotService(t, newGameService()), time.Minute, 0),
 		Invitations: newInvitationService(),
+		GameLimits:  gl,
 	})
 
-	human := provisionAccount(t)
+	guest := provisionGuest(t)
+	if gamesListAtLimit(t, srv, guest) {
+		t.Fatal("a fresh guest must be under the random game limit")
+	}
+	// The first auto-match opens a random game (guest random cap = 1).
+	if rec := userPost(t, srv, "/api/v1/user/lobby/enqueue", guest, `{"variant":"erudit_ru"}`); rec.Code != http.StatusOK {
+		t.Fatalf("first enqueue = %d (%s), want 200", rec.Code, rec.Body.String())
+	}
+	// At the cap: the lobby flags it and a second enqueue is refused with the stable code.
+	if !gamesListAtLimit(t, srv, guest) {
+		t.Fatal("after one random game the guest must be at the limit")
+	}
+	if rec := userPost(t, srv, "/api/v1/user/lobby/enqueue", guest, `{"variant":"erudit_ru"}`); rec.Code != http.StatusConflict || errorCode(t, rec) != "game_limit_reached" {
+		t.Fatalf("second enqueue = (%d, %q), want (409, game_limit_reached)", rec.Code, errorCode(t, rec))
+	}
+
+	// A guest is refused the friends flow outright at the HTTP edge (403 guest_forbidden).
 	opp := provisionAccount(t)
-
-	// Under the cap: the lobby reports the player is not limited.
-	if gamesListAtLimit(t, srv, human) {
-		t.Fatal("a fresh account must be under the game limit")
-	}
-
-	// Reach the cap with active quick games seating the human (no invitation row → quick).
-	for i := 0; i < game.MaxActiveQuickGames; i++ {
-		mustCreateQuick(t, games, []uuid.UUID{human, opp}, false, int64(i+1))
-	}
-
-	// At the cap: the lobby flags it and both create paths are refused with the stable code.
-	if !gamesListAtLimit(t, srv, human) {
-		t.Fatalf("at %d games at_game_limit must be true", game.MaxActiveQuickGames)
-	}
-	// erudit_ru is in the default variant preferences, so the variant gate passes and the
-	// game-limit gate is what fires here.
-	if rec := userPost(t, srv, "/api/v1/user/lobby/enqueue", human, `{"variant":"erudit_ru"}`); rec.Code != http.StatusConflict || errorCode(t, rec) != "game_limit_reached" {
-		t.Fatalf("enqueue at limit = (%d, %q), want (409, game_limit_reached)", rec.Code, errorCode(t, rec))
-	}
 	invBody := fmt.Sprintf(`{"variant":"erudit_ru","invitee_ids":[%q]}`, opp.String())
-	if rec := userPost(t, srv, "/api/v1/user/invitations", human, invBody); rec.Code != http.StatusConflict || errorCode(t, rec) != "game_limit_reached" {
-		t.Fatalf("invitation at limit = (%d, %q), want (409, game_limit_reached)", rec.Code, errorCode(t, rec))
+	if rec := userPost(t, srv, "/api/v1/user/invitations", guest, invBody); rec.Code != http.StatusForbidden || errorCode(t, rec) != "guest_forbidden" {
+		t.Fatalf("guest invitation = (%d, %q), want (403, guest_forbidden)", rec.Code, errorCode(t, rec))
 	}
 
-	// Accepting an incoming invitation is never blocked, even at the cap: another player invites
-	// the capped human, who accepts over HTTP and the game starts (friend games do not count).
-	inviter := provisionAccount(t)
-	inv := newInvitationService()
-	invitation, err := inv.CreateInvitation(ctx, inviter, []uuid.UUID{human}, englishInvite())
-	if err != nil {
-		t.Fatalf("create invitation: %v", err)
+	// The guest vs_ai cap is 1: one vs_ai game puts the guest at the vs_ai limit.
+	mustCreateKind(t, games, []uuid.UUID{guest, opp}, gamelimits.KindVsAI)
+	if at, err := games.AtGameLimit(ctx, guest, gamelimits.KindVsAI); err != nil || !at {
+		t.Fatalf("guest vs_ai at-limit = (%v, %v), want (true, nil)", at, err)
 	}
-	if rec := userPost(t, srv, "/api/v1/user/invitations/"+invitation.ID.String()+"/accept", human, ""); rec.Code != http.StatusOK {
-		t.Fatalf("accept at limit = %d (%s), want 200 — accept must bypass the cap", rec.Code, rec.Body.String())
+	// The guest friends cap is 0: a guest is always at the friends limit (the 403 gate blocks first).
+	if at, err := games.AtGameLimit(ctx, guest, gamelimits.KindFriends); err != nil || !at {
+		t.Fatalf("guest friends at-limit = (%v, %v), want (true, nil)", at, err)
 	}
 }
 
-// mustCount returns the account's active-quick-game count, failing on error.
-func mustCount(t *testing.T, games *game.Service, id uuid.UUID) int {
-	t.Helper()
-	n, err := games.CountActiveQuickGames(context.Background(), id)
-	if err != nil {
-		t.Fatalf("count active quick games: %v", err)
-	}
-	return n
-}
-
-// mustCreateQuick creates an active quick game (no invitation) seating the given accounts and
-// returns its id; vsAI flags an honest-AI game (the service then applies the 7-day clock).
-func mustCreateQuick(t *testing.T, games *game.Service, seats []uuid.UUID, vsAI bool, seed int64) uuid.UUID {
-	t.Helper()
-	p := game.CreateParams{Variant: engine.VariantEnglish, Seats: seats, TurnTimeout: 24 * time.Hour, Seed: seed}
-	if vsAI {
-		p.VsAI = true
-		p.TurnTimeout = 0 // the service applies the 7-day AI inactivity clock for vs_ai games
-	}
-	g, err := games.Create(context.Background(), p)
-	if err != nil {
-		t.Fatalf("create quick game (vsAI=%v): %v", vsAI, err)
-	}
-	return g.ID
-}
-
-// startFriendGame has a fresh inviter invite the given account to a friend game and the invitee
-// accept it, so the (active) friend game exists with its game_invitations row.
-func startFriendGame(t *testing.T, invitee uuid.UUID) {
-	t.Helper()
+// TestDurableTierHigherLimit checks a durable account resolves the durable tier, not the guest one:
+// one random game leaves it well under the durable cap (10).
+func TestDurableTierHigherLimit(t *testing.T) {
 	ctx := context.Background()
+	gl := newGameLimits(t)
+	games := newGameService()
+	games.SetGameLimits(gl)
+	durable, opp := provisionAccount(t), provisionAccount(t)
+
+	mustCreateKind(t, games, []uuid.UUID{durable, opp}, gamelimits.KindRandom)
+	if at, err := games.AtGameLimit(ctx, durable, gamelimits.KindRandom); err != nil || at {
+		t.Fatalf("durable random at-limit after one game = (%v, %v), want (false, nil)", at, err)
+	}
+}
+
+// TestGuestForbiddenFriendActions checks a guest is refused every friend action server-side (the UI
+// hides them; this is the source of truth): creating an invitation, sending a friend request, and
+// redeeming a friend code.
+func TestGuestForbiddenFriendActions(t *testing.T) {
+	ctx := context.Background()
+	guest := provisionGuest(t)
+	other := provisionAccount(t)
+
 	inv := newInvitationService()
+	if _, err := inv.CreateInvitation(ctx, guest, []uuid.UUID{other}, englishInvite()); !errors.Is(err, lobby.ErrGuestForbidden) {
+		t.Fatalf("guest CreateInvitation err = %v, want ErrGuestForbidden", err)
+	}
+
+	soc := newSocialService()
+	if err := soc.SendFriendRequest(ctx, guest, other); !errors.Is(err, social.ErrGuestForbidden) {
+		t.Fatalf("guest SendFriendRequest err = %v, want ErrGuestForbidden", err)
+	}
+	if _, err := soc.RedeemFriendCode(ctx, guest, "000000"); !errors.Is(err, social.ErrGuestForbidden) {
+		t.Fatalf("guest RedeemFriendCode err = %v, want ErrGuestForbidden", err)
+	}
+}
+
+// TestDurableFriendsCapAndConfigCache lowers the durable friends cap to 1 through the service (the
+// admin-edit path), checks a durable inviter is refused a second friend game with 409, and that
+// accepting an incoming invitation is still exempt from the cap.
+func TestDurableFriendsCapAndConfigCache(t *testing.T) {
+	ctx := context.Background()
+	gl := newGameLimits(t)
+	restoreDefaultLimits(t, gl)
+	cfg := gl.Get()
+	cfg.Durable.Friends = 1
+	if err := gl.Update(ctx, cfg); err != nil {
+		t.Fatalf("update durable friends cap: %v", err)
+	}
+	games := newGameService()
+	games.SetGameLimits(gl)
+	inv := lobby.NewInvitationService(lobby.NewStore(testDB), games, account.NewStore(testDB), newSocialService())
+
 	inviter := provisionAccount(t)
-	invitation, err := inv.CreateInvitation(ctx, inviter, []uuid.UUID{invitee}, englishInvite())
-	if err != nil {
-		t.Fatalf("create invitation: %v", err)
+	d2, d3 := provisionAccount(t), provisionAccount(t)
+
+	// The inviter's first friend game reaches the (lowered) cap of 1.
+	startFriendGameID(t, inv, inviter, d2)
+	if at, err := games.AtGameLimit(ctx, inviter, gamelimits.KindFriends); err != nil || !at {
+		t.Fatalf("inviter friends at-limit = (%v, %v), want (true, nil)", at, err)
 	}
-	if _, err := inv.RespondInvitation(ctx, invitation.ID, invitee, true); err != nil {
-		t.Fatalf("accept invitation: %v", err)
+	// A second invitation is refused: the cache reflects the edit.
+	if _, err := inv.CreateInvitation(ctx, inviter, []uuid.UUID{d3}, englishInvite()); !errors.Is(err, game.ErrGameLimitReached) {
+		t.Fatalf("second invitation err = %v, want ErrGameLimitReached", err)
 	}
+	// Accept stays exempt: someone else invites the capped inviter, who accepts and the game starts.
+	startFriendGameID(t, inv, d3, inviter)
 }
 
 // gamesListAtLimit fetches /api/v1/user/games and returns its at_game_limit flag.

backend/internal/lobby/invitations.go

@@ -15,6 +15,7 @@ import (
 	"scrabble/backend/internal/account"
 	"scrabble/backend/internal/engine"
 	"scrabble/backend/internal/game"
+	"scrabble/backend/internal/gamelimits"
 	"scrabble/backend/internal/notify"
 	"scrabble/backend/internal/postgres/jet/backend/model"
 	"scrabble/backend/internal/postgres/jet/backend/table"
@@ -218,6 +219,20 @@ func (svc *InvitationService) CreateInvitation(ctx context.Context, inviterID uu
 	if !slices.Contains(game.AllowedTurnTimeouts, settings.TurnTimeout) {
 		return Invitation{}, fmt.Errorf("%w: turn timeout %s not allowed", ErrInvalidInvitation, settings.TurnTimeout)
 	}
+	// A guest cannot invite: friend games are a durable-account feature. The UI hides the flow;
+	// this is the server source of truth.
+	if acc, err := svc.accounts.GetByID(ctx, inviterID); err != nil {
+		return Invitation{}, err
+	} else if acc.IsGuest {
+		return Invitation{}, ErrGuestForbidden
+	}
+	// A durable inviter is still capped: refuse a new friend game once the per-tier friends limit is
+	// reached. The guest branch above short-circuits before here, so this is the durable cap.
+	if atLimit, err := svc.games.AtGameLimit(ctx, inviterID, gamelimits.KindFriends); err != nil {
+		return Invitation{}, err
+	} else if atLimit {
+		return Invitation{}, game.ErrGameLimitReached
+	}
 	seen := map[uuid.UUID]bool{inviterID: true}
 	// suppressed collects invitees who have blocked the inviter: the invitation is still
 	// created and persisted for them, but they are never notified and never see it (their
@@ -336,6 +351,7 @@ func (svc *InvitationService) startGame(ctx context.Context, invitationID uuid.U
 		HintsPerPlayer:       inv.Settings.HintsPerPlayer,
 		DropoutTiles:         inv.Settings.DropoutTiles,
 		MultipleWordsPerTurn: inv.Settings.MultipleWordsPerTurn,
+		Kind:                 gamelimits.KindFriends,
 	})
 	if err != nil {
 		return err

backend/internal/lobby/lobby.go

@@ -15,17 +15,22 @@ import (
 
 	"scrabble/backend/internal/engine"
 	"scrabble/backend/internal/game"
+	"scrabble/backend/internal/gamelimits"
 	"scrabble/backend/internal/notify"
 )
 
 // GameCreator is the slice of the game domain the lobby needs: starting a seated
-// game and reading a player's initial view of it. game.Service satisfies it.
+// game, reading a player's initial view of it, and testing a caller's active-game
+// cap. game.Service satisfies it.
 type GameCreator interface {
 	Create(ctx context.Context, params game.CreateParams) (game.Game, error)
 	// InitialState returns a seated player's full initial view of a started game, used
 	// to enrich the game_started event so the client renders the new game without a
 	// follow-up fetch.
 	InitialState(ctx context.Context, gameID, accountID uuid.UUID) (notify.PlayerState, error)
+	// AtGameLimit reports whether accountID has reached its tier's active-game cap for kind. The
+	// invitation path uses it to enforce the friends limit before opening one.
+	AtGameLimit(ctx context.Context, accountID uuid.UUID, kind gamelimits.Kind) (bool, error)
 }
 
 // RobotProvider supplies a robot account to substitute for a missing human in
@@ -62,6 +67,9 @@ var (
 	// ErrInvalidInvitation is returned for a malformed invitation (bad player
 	// count, duplicate or self invitee, or unacceptable settings).
 	ErrInvalidInvitation = errors.New("lobby: invalid invitation")
+	// ErrGuestForbidden is returned when a guest attempts a durable-only action (invite a
+	// friend); the friend flow is gated to durable accounts.
+	ErrGuestForbidden = errors.New("lobby: guests cannot invite")
 	// ErrInvitationBlocked is returned when a block stands between the inviter and
 	// an invitee.
 	ErrInvitationBlocked = errors.New("lobby: invitation blocked between accounts")

backend/internal/lobby/matchmaker.go

@@ -10,6 +10,7 @@ import (
 
 	"scrabble/backend/internal/engine"
 	"scrabble/backend/internal/game"
+	"scrabble/backend/internal/gamelimits"
 	"scrabble/backend/internal/notify"
 )
 
@@ -141,6 +142,7 @@ func (m *Matchmaker) StartVsAI(ctx context.Context, accountID uuid.UUID, variant
 	if rand.IntN(2) == 1 {
 		params.Seats = []uuid.UUID{robotID, accountID}
 	}
+	params.Kind = gamelimits.KindVsAI
 	g, err := m.games.Create(ctx, params)
 	if err != nil {
 		return EnqueueResult{}, err

backend/internal/postgres/jet/backend/model/config.go

@@ -0,0 +1,18 @@
+//
+// Code generated by go-jet DO NOT EDIT.
+//
+// WARNING: Changes to this file may cause incorrect behavior
+// and will be lost if the code is regenerated
+//
+
+package model
+
+type Config struct {
+	OnlyRow             bool `sql:"primary_key"`
+	GuestVsAiLimit      int16
+	GuestRandomLimit    int16
+	GuestFriendsLimit   int16
+	DurableVsAiLimit    int16
+	DurableRandomLimit  int16
+	DurableFriendsLimit int16
+}

backend/internal/postgres/jet/backend/model/games.go

@@ -33,4 +33,5 @@ type Games struct {
 	DropoutTiles         string
 	MultipleWordsPerTurn bool
 	VsAi                 bool
+	GameKind             int16
 }

backend/internal/postgres/jet/backend/table/config.go

@@ -0,0 +1,96 @@
+//
+// Code generated by go-jet DO NOT EDIT.
+//
+// WARNING: Changes to this file may cause incorrect behavior
+// and will be lost if the code is regenerated
+//
+
+package table
+
+import (
+	"github.com/go-jet/jet/v2/postgres"
+)
+
+var Config = newConfigTable("backend", "config", "")
+
+type configTable struct {
+	postgres.Table
+
+	// Columns
+	OnlyRow             postgres.ColumnBool
+	GuestVsAiLimit      postgres.ColumnInteger
+	GuestRandomLimit    postgres.ColumnInteger
+	GuestFriendsLimit   postgres.ColumnInteger
+	DurableVsAiLimit    postgres.ColumnInteger
+	DurableRandomLimit  postgres.ColumnInteger
+	DurableFriendsLimit postgres.ColumnInteger
+
+	AllColumns     postgres.ColumnList
+	MutableColumns postgres.ColumnList
+	DefaultColumns postgres.ColumnList
+}
+
+type ConfigTable struct {
+	configTable
+
+	EXCLUDED configTable
+}
+
+// AS creates new ConfigTable with assigned alias
+func (a ConfigTable) AS(alias string) *ConfigTable {
+	return newConfigTable(a.SchemaName(), a.TableName(), alias)
+}
+
+// Schema creates new ConfigTable with assigned schema name
+func (a ConfigTable) FromSchema(schemaName string) *ConfigTable {
+	return newConfigTable(schemaName, a.TableName(), a.Alias())
+}
+
+// WithPrefix creates new ConfigTable with assigned table prefix
+func (a ConfigTable) WithPrefix(prefix string) *ConfigTable {
+	return newConfigTable(a.SchemaName(), prefix+a.TableName(), a.TableName())
+}
+
+// WithSuffix creates new ConfigTable with assigned table suffix
+func (a ConfigTable) WithSuffix(suffix string) *ConfigTable {
+	return newConfigTable(a.SchemaName(), a.TableName()+suffix, a.TableName())
+}
+
+func newConfigTable(schemaName, tableName, alias string) *ConfigTable {
+	return &ConfigTable{
+		configTable: newConfigTableImpl(schemaName, tableName, alias),
+		EXCLUDED:    newConfigTableImpl("", "excluded", ""),
+	}
+}
+
+func newConfigTableImpl(schemaName, tableName, alias string) configTable {
+	var (
+		OnlyRowColumn             = postgres.BoolColumn("only_row")
+		GuestVsAiLimitColumn      = postgres.IntegerColumn("guest_vs_ai_limit")
+		GuestRandomLimitColumn    = postgres.IntegerColumn("guest_random_limit")
+		GuestFriendsLimitColumn   = postgres.IntegerColumn("guest_friends_limit")
+		DurableVsAiLimitColumn    = postgres.IntegerColumn("durable_vs_ai_limit")
+		DurableRandomLimitColumn  = postgres.IntegerColumn("durable_random_limit")
+		DurableFriendsLimitColumn = postgres.IntegerColumn("durable_friends_limit")
+		allColumns                = postgres.ColumnList{OnlyRowColumn, GuestVsAiLimitColumn, GuestRandomLimitColumn, GuestFriendsLimitColumn, DurableVsAiLimitColumn, DurableRandomLimitColumn, DurableFriendsLimitColumn}
+		mutableColumns            = postgres.ColumnList{GuestVsAiLimitColumn, GuestRandomLimitColumn, GuestFriendsLimitColumn, DurableVsAiLimitColumn, DurableRandomLimitColumn, DurableFriendsLimitColumn}
+		defaultColumns            = postgres.ColumnList{OnlyRowColumn, GuestVsAiLimitColumn, GuestRandomLimitColumn, GuestFriendsLimitColumn, DurableVsAiLimitColumn, DurableRandomLimitColumn, DurableFriendsLimitColumn}
+	)
+
+	return configTable{
+		Table: postgres.NewTable(schemaName, tableName, alias, allColumns...),
+
+		//Columns
+		OnlyRow:             OnlyRowColumn,
+		GuestVsAiLimit:      GuestVsAiLimitColumn,
+		GuestRandomLimit:    GuestRandomLimitColumn,
+		GuestFriendsLimit:   GuestFriendsLimitColumn,
+		DurableVsAiLimit:    DurableVsAiLimitColumn,
+		DurableRandomLimit:  DurableRandomLimitColumn,
+		DurableFriendsLimit: DurableFriendsLimitColumn,
+
+		AllColumns:     allColumns,
+		MutableColumns: mutableColumns,
+		DefaultColumns: defaultColumns,
+	}
+}

backend/internal/postgres/jet/backend/table/games.go

@@ -37,6 +37,7 @@ type gamesTable struct {
 	DropoutTiles         postgres.ColumnString
 	MultipleWordsPerTurn postgres.ColumnBool
 	VsAi                 postgres.ColumnBool
+	GameKind             postgres.ColumnInteger
 
 	AllColumns     postgres.ColumnList
 	MutableColumns postgres.ColumnList
@@ -98,9 +99,10 @@ func newGamesTableImpl(schemaName, tableName, alias string) gamesTable {
 		DropoutTilesColumn         = postgres.StringColumn("dropout_tiles")
 		MultipleWordsPerTurnColumn = postgres.BoolColumn("multiple_words_per_turn")
 		VsAiColumn                 = postgres.BoolColumn("vs_ai")
-		allColumns                 = postgres.ColumnList{GameIDColumn, VariantColumn, DictVersionColumn, SeedColumn, StatusColumn, PlayersColumn, ToMoveColumn, TurnStartedAtColumn, TurnTimeoutSecsColumn, HintsAllowedColumn, HintsPerPlayerColumn, MoveCountColumn, EndReasonColumn, CreatedAtColumn, UpdatedAtColumn, FinishedAtColumn, OpenDeadlineAtColumn, DropoutTilesColumn, MultipleWordsPerTurnColumn, VsAiColumn}
-		mutableColumns             = postgres.ColumnList{VariantColumn, DictVersionColumn, SeedColumn, StatusColumn, PlayersColumn, ToMoveColumn, TurnStartedAtColumn, TurnTimeoutSecsColumn, HintsAllowedColumn, HintsPerPlayerColumn, MoveCountColumn, EndReasonColumn, CreatedAtColumn, UpdatedAtColumn, FinishedAtColumn, OpenDeadlineAtColumn, DropoutTilesColumn, MultipleWordsPerTurnColumn, VsAiColumn}
-		defaultColumns             = postgres.ColumnList{StatusColumn, ToMoveColumn, TurnStartedAtColumn, HintsAllowedColumn, HintsPerPlayerColumn, MoveCountColumn, CreatedAtColumn, UpdatedAtColumn, DropoutTilesColumn, MultipleWordsPerTurnColumn, VsAiColumn}
+		GameKindColumn             = postgres.IntegerColumn("game_kind")
+		allColumns                 = postgres.ColumnList{GameIDColumn, VariantColumn, DictVersionColumn, SeedColumn, StatusColumn, PlayersColumn, ToMoveColumn, TurnStartedAtColumn, TurnTimeoutSecsColumn, HintsAllowedColumn, HintsPerPlayerColumn, MoveCountColumn, EndReasonColumn, CreatedAtColumn, UpdatedAtColumn, FinishedAtColumn, OpenDeadlineAtColumn, DropoutTilesColumn, MultipleWordsPerTurnColumn, VsAiColumn, GameKindColumn}
+		mutableColumns             = postgres.ColumnList{VariantColumn, DictVersionColumn, SeedColumn, StatusColumn, PlayersColumn, ToMoveColumn, TurnStartedAtColumn, TurnTimeoutSecsColumn, HintsAllowedColumn, HintsPerPlayerColumn, MoveCountColumn, EndReasonColumn, CreatedAtColumn, UpdatedAtColumn, FinishedAtColumn, OpenDeadlineAtColumn, DropoutTilesColumn, MultipleWordsPerTurnColumn, VsAiColumn, GameKindColumn}
+		defaultColumns             = postgres.ColumnList{StatusColumn, ToMoveColumn, TurnStartedAtColumn, HintsAllowedColumn, HintsPerPlayerColumn, MoveCountColumn, CreatedAtColumn, UpdatedAtColumn, DropoutTilesColumn, MultipleWordsPerTurnColumn, VsAiColumn, GameKindColumn}
 	)
 
 	return gamesTable{
@@ -127,6 +129,7 @@ func newGamesTableImpl(schemaName, tableName, alias string) gamesTable {
 		DropoutTiles:         DropoutTilesColumn,
 		MultipleWordsPerTurn: MultipleWordsPerTurnColumn,
 		VsAi:                 VsAiColumn,
+		GameKind:             GameKindColumn,
 
 		AllColumns:     allColumns,
 		MutableColumns: mutableColumns,

backend/internal/postgres/jet/backend/table/table_use_schema.go

@@ -21,6 +21,7 @@ func UseSchema(schema string) {
 	Blocks = Blocks.FromSchema(schema)
 	ChatMessages = ChatMessages.FromSchema(schema)
 	Complaints = Complaints.FromSchema(schema)
+	Config = Config.FromSchema(schema)
 	DictionaryState = DictionaryState.FromSchema(schema)
 	EmailConfirmations = EmailConfirmations.FromSchema(schema)
 	FeedbackMessages = FeedbackMessages.FromSchema(schema)

backend/internal/postgres/migrations/00014_guest_limits.sql

@@ -0,0 +1,36 @@
+-- Guest-limit foundation (E8): tag each game with its kind so the per-tier, per-kind active-game
+-- limits are enforceable, and add the single-row config that holds those limits (tuned in the admin,
+-- no release). It replaces the old hardcoded MaxActiveQuickGames=10 combined cap with a per-tier,
+-- per-kind config. game_kind: 0=unknown (pre-E8 games, never gated), 1=vs_ai, 2=random, 3=friends —
+-- set on creation. The limits are smallint with -1 = unlimited; a guest defaults to 1 vs_ai + 1
+-- random (friends 0, moot — the guest gate blocks friend games), a durable account to 10 per kind
+-- (the old cap, now per kind). Additive only — applies forward via goose with no data rewrite (no
+-- contour wipe); an image rollback ignores the column + table.
+-- +goose Up
+
+ALTER TABLE backend.games
+    ADD COLUMN game_kind smallint DEFAULT 0 NOT NULL;
+ALTER TABLE backend.games
+    ADD CONSTRAINT games_game_kind_chk CHECK (game_kind >= 0 AND game_kind <= 3);
+
+CREATE TABLE backend.config (
+    only_row boolean DEFAULT true NOT NULL,
+    guest_vs_ai_limit smallint DEFAULT 1 NOT NULL,
+    guest_random_limit smallint DEFAULT 1 NOT NULL,
+    guest_friends_limit smallint DEFAULT 0 NOT NULL,
+    durable_vs_ai_limit smallint DEFAULT 10 NOT NULL,
+    durable_random_limit smallint DEFAULT 10 NOT NULL,
+    durable_friends_limit smallint DEFAULT 10 NOT NULL,
+    CONSTRAINT config_pkey PRIMARY KEY (only_row),
+    CONSTRAINT config_single_row_chk CHECK (only_row),
+    CONSTRAINT config_limits_chk CHECK (
+        guest_vs_ai_limit >= -1 AND guest_random_limit >= -1 AND guest_friends_limit >= -1 AND
+        durable_vs_ai_limit >= -1 AND durable_random_limit >= -1 AND durable_friends_limit >= -1)
+);
+
+INSERT INTO backend.config (only_row) VALUES (true);
+
+-- +goose Down
+
+DROP TABLE backend.config;
+ALTER TABLE backend.games DROP COLUMN game_kind;

backend/internal/server/handlers.go

@@ -319,6 +319,8 @@ func statusForError(err error) (int, string) {
 		return http.StatusConflict, "request_declined"
 	case errors.Is(err, social.ErrFriendCodeInvalid):
 		return http.StatusUnprocessableEntity, "friend_code_invalid"
+	case errors.Is(err, social.ErrGuestForbidden), errors.Is(err, lobby.ErrGuestForbidden):
+		return http.StatusForbidden, "guest_forbidden"
 	case errors.Is(err, feedback.ErrGuestForbidden):
 		return http.StatusForbidden, "feedback_guest_forbidden"
 	case errors.Is(err, feedback.ErrBanned):

backend/internal/server/handlers_admin_console.go

@@ -70,6 +70,10 @@ func (s *Server) registerConsole(router *gin.Engine) {
 	gm.POST("/bans/unban", s.consoleUnban)
 	gm.GET("/games", s.consoleGames)
 	gm.GET("/games/:id", s.consoleGameDetail)
+	if s.gamelimits != nil {
+		gm.GET("/limits", s.consoleLimits)
+		gm.POST("/limits", s.consoleUpdateLimits)
+	}
 	gm.GET("/complaints", s.consoleComplaints)
 	gm.GET("/complaints/:id", s.consoleComplaintDetail)
 	gm.POST("/complaints/:id/resolve", s.consoleResolveComplaint)
@@ -1244,7 +1248,7 @@ func (s *Server) consoleUUID(c *gin.Context, back string) (uuid.UUID, bool) {
 
 // gameRow projects a game summary into its console row.
 func gameRow(g game.Game) adminconsole.GameRow {
-	return adminconsole.GameRow{ID: g.ID.String(), Variant: g.Variant.String(), Status: g.Status, Players: g.Players, UpdatedAt: fmtTime(g.UpdatedAt), VsAI: g.VsAI}
+	return adminconsole.GameRow{ID: g.ID.String(), Variant: g.Variant.String(), Status: g.Status, Players: g.Players, UpdatedAt: fmtTime(g.UpdatedAt), VsAI: g.VsAI, Kind: g.Kind.String()}
 }
 
 // trimForm returns the trimmed value of a posted form field.

backend/internal/server/handlers_admin_limits.go

@@ -0,0 +1,65 @@
+package server
+
+import (
+	"fmt"
+
+	"github.com/gin-gonic/gin"
+
+	"scrabble/backend/internal/adminconsole"
+	"scrabble/backend/internal/gamelimits"
+)
+
+// consoleLimits renders the per-tier, per-kind active-game limit form (backend.config), read from
+// the in-memory cache.
+func (s *Server) consoleLimits(c *gin.Context) {
+	cfg := s.gamelimits.Get()
+	s.renderConsole(c, "limits", "limits", "Game limits", adminconsole.GameLimitsView{
+		GuestVsAI:      cfg.Guest.VsAI,
+		GuestRandom:    cfg.Guest.Random,
+		GuestFriends:   cfg.Guest.Friends,
+		DurableVsAI:    cfg.Durable.VsAI,
+		DurableRandom:  cfg.Durable.Random,
+		DurableFriends: cfg.Durable.Friends,
+	})
+}
+
+// consoleUpdateLimits saves the active-game limits and refreshes the hot cache in place. Each
+// field is a per-kind cap: -1 is unlimited, 0 blocks the kind, a positive value caps concurrent games.
+func (s *Server) consoleUpdateLimits(c *gin.Context) {
+	cfg := gamelimits.Config{
+		Guest: gamelimits.Limits{
+			VsAI:    atoiForm(c, "guest_vs_ai"),
+			Random:  atoiForm(c, "guest_random"),
+			Friends: atoiForm(c, "guest_friends"),
+		},
+		Durable: gamelimits.Limits{
+			VsAI:    atoiForm(c, "durable_vs_ai"),
+			Random:  atoiForm(c, "durable_random"),
+			Friends: atoiForm(c, "durable_friends"),
+		},
+	}
+	if err := validateGameLimits(cfg); err != nil {
+		s.renderConsoleMessage(c, "Invalid", err.Error(), "/_gm/limits")
+		return
+	}
+	if err := s.gamelimits.Update(c.Request.Context(), cfg); err != nil {
+		s.consoleError(c, err)
+		return
+	}
+	s.renderConsoleMessage(c, "Saved", "game limits updated", "/_gm/limits")
+}
+
+// validateGameLimits rejects a limit below -1 (the unlimited sentinel); -1, 0 and any positive count
+// are valid. It mirrors the backend.config CHECK so a bad value is refused with a clean message
+// rather than a raw database error.
+func validateGameLimits(cfg gamelimits.Config) error {
+	for _, v := range []int{
+		cfg.Guest.VsAI, cfg.Guest.Random, cfg.Guest.Friends,
+		cfg.Durable.VsAI, cfg.Durable.Random, cfg.Durable.Friends,
+	} {
+		if v < gamelimits.Unlimited {
+			return fmt.Errorf("a limit must be -1 (unlimited), 0, or a positive count")
+		}
+	}
+	return nil
+}

backend/internal/server/handlers_game.go

@@ -10,6 +10,7 @@ import (
 
 	"scrabble/backend/internal/engine"
 	"scrabble/backend/internal/game"
+	"scrabble/backend/internal/gamelimits"
 )
 
 // The handlers below cover the game and chat operations the UI needs. They follow
@@ -46,10 +47,11 @@ type historyDTO struct {
 }
 
 // gameListDTO is the caller's games (active and finished) for the lobby. AtGameLimit
-// reports whether the caller has reached the simultaneous quick-game cap
-// (game.MaxActiveQuickGames); while it is true the lobby disables "New Game" and shows a
-// notice. It rides the lobby response — which the lobby re-fetches on every game event —
-// instead of a separate request.
+// reports whether the caller has reached its tier's active-game cap for the random
+// (quick auto-match) kind (the per-tier, per-kind limits in backend.config); while
+// it is true the lobby disables "New Game" and shows a notice. It rides the lobby
+// response — which the lobby re-fetches on every game event — instead of a separate
+// request.
 type gameListDTO struct {
 	Games       []gameDTO `json:"games"`
 	AtGameLimit bool      `json:"at_game_limit"`
@@ -395,23 +397,13 @@ func (s *Server) handleSaveDraft(c *gin.Context) {
 	c.JSON(http.StatusOK, okResponse{OK: true})
 }
 
-// atGameLimit reports whether uid already holds the maximum number of simultaneous
-// quick games (game.MaxActiveQuickGames). It backs both the lobby's at_game_limit flag
-// and the new-game gate; friend games created by invitation are not counted.
-func (s *Server) atGameLimit(ctx context.Context, uid uuid.UUID) (bool, error) {
-	n, err := s.games.CountActiveQuickGames(ctx, uid)
-	if err != nil {
-		return false, err
-	}
-	return n >= game.MaxActiveQuickGames, nil
-}
-
-// ensureUnderGameLimit aborts the request with 409 game_limit_reached when uid is at the
-// simultaneous quick-game cap, and reports whether the caller may proceed. It guards
-// every new-game entry point — quick auto-match/AI and invitation creation; accepting an
-// incoming invitation is deliberately exempt.
-func (s *Server) ensureUnderGameLimit(c *gin.Context, uid uuid.UUID) bool {
-	atLimit, err := s.atGameLimit(c.Request.Context(), uid)
+// ensureUnderGameLimit aborts the request with 409 game_limit_reached when uid has reached its
+// tier's active-game cap for kind (the per-tier, per-kind limits in backend.config), and reports
+// whether the caller may proceed. It guards the quick new-game entry points — auto-match (random)
+// and AI (vs_ai). Friend-invitation limits are enforced in the lobby's CreateInvitation, and
+// accepting an incoming invitation is deliberately exempt.
+func (s *Server) ensureUnderGameLimit(c *gin.Context, uid uuid.UUID, kind gamelimits.Kind) bool {
+	atLimit, err := s.games.AtGameLimit(c.Request.Context(), uid, kind)
 	if err != nil {
 		s.abortErr(c, err)
 		return false
@@ -437,7 +429,7 @@ func (s *Server) handleListGames(c *gin.Context) {
 		s.abortErr(c, err)
 		return
 	}
-	atLimit, err := s.atGameLimit(c.Request.Context(), uid)
+	atLimit, err := s.games.AtGameLimit(c.Request.Context(), uid, gamelimits.KindRandom)
 	if err != nil {
 		s.abortErr(c, err)
 		return

backend/internal/server/handlers_invitations.go

@@ -133,9 +133,6 @@ func (s *Server) handleCreateInvitation(c *gin.Context) {
 		}
 		inviteeIDs = append(inviteeIDs, id)
 	}
-	if !s.ensureUnderGameLimit(c, uid) {
-		return
-	}
 	inv, err := s.invitations.CreateInvitation(c.Request.Context(), uid, inviteeIDs, settings)
 	if err != nil {
 		s.abortErr(c, err)

backend/internal/server/handlers_user.go

@@ -8,6 +8,7 @@ import (
 	"github.com/google/uuid"
 
 	"scrabble/backend/internal/engine"
+	"scrabble/backend/internal/gamelimits"
 )
 
 // The /api/v1/user/* endpoints require X-User-ID (RequireUserID middleware). The
@@ -189,13 +190,15 @@ func (s *Server) handleEnqueue(c *gin.Context) {
 	if !s.ensureVariantAllowed(c, uid, variant.String()) {
 		return
 	}
-	if !s.ensureUnderGameLimit(c, uid) {
-		return
-	}
+	kind := gamelimits.KindRandom
 	enter := s.matchmaker.Enqueue
 	if req.VsAI {
+		kind = gamelimits.KindVsAI
 		enter = s.matchmaker.StartVsAI
 	}
+	if !s.ensureUnderGameLimit(c, uid, kind) {
+		return
+	}
 	res, err := enter(c.Request.Context(), uid, variant, req.MultipleWordsPerTurn)
 	if err != nil {
 		s.abortErr(c, err)

backend/internal/server/server.go

@@ -25,6 +25,7 @@ import (
 	"scrabble/backend/internal/engine"
 	"scrabble/backend/internal/feedback"
 	"scrabble/backend/internal/game"
+	"scrabble/backend/internal/gamelimits"
 	"scrabble/backend/internal/link"
 	"scrabble/backend/internal/lobby"
 	"scrabble/backend/internal/notify"
@@ -100,6 +101,10 @@ type Deps struct {
 	// console routes are registered when the wallet surface lands. A nil Payments
 	// omits them.
 	Payments *payments.Service
+	// GameLimits is the per-tier, per-kind active-game limit config, cached in memory. The
+	// game domain reads it through game.Service (SetGameLimits) for the new-game gate; the admin
+	// console reads and edits it here. A nil GameLimits omits the limits console section.
+	GameLimits *gamelimits.Service
 	// Notifier publishes live-event intents — here the banner-eligibility re-poll
 	// signal the banner/hint/role console actions emit. A nil Notifier discards
 	// them (notify.Nop).
@@ -140,6 +145,7 @@ type Server struct {
 	banview     *banview.View
 	ads         *ads.Service
 	payments    *payments.Service
+	gamelimits  *gamelimits.Service
 	robokassa   robokassa.Config
 	notifier    notify.Publisher
 	console     *adminconsole.Renderer
@@ -194,6 +200,7 @@ func New(addr string, deps Deps) *Server {
 		banview:       deps.BanView,
 		ads:           deps.Ads,
 		payments:      deps.Payments,
+		gamelimits:    deps.GameLimits,
 		robokassa:     deps.Robokassa,
 		notifier:      notifier,
 		renderer:      deps.Renderer,

backend/internal/social/friendcodes.go

@@ -65,6 +65,12 @@ func (svc *Service) IssueFriendCode(ctx context.Context, accountID uuid.UUID) (F
 // ErrRequestBlocked (a block stands between the pair). A redeem bypasses any prior
 // decline between the two: it clears the old row and writes a fresh friendship.
 func (svc *Service) RedeemFriendCode(ctx context.Context, redeemerID uuid.UUID, code string) (uuid.UUID, error) {
+	// A guest cannot use friends: a durable-account feature (the UI hides it).
+	if acc, err := svc.accounts.GetByID(ctx, redeemerID); err != nil {
+		return uuid.UUID{}, err
+	} else if acc.IsGuest {
+		return uuid.UUID{}, ErrGuestForbidden
+	}
 	issuerID, codeID, err := svc.store.liveFriendCodeByHash(ctx, hashFriendCode(code), svc.now())
 	if err != nil {
 		return uuid.UUID{}, err

backend/internal/social/friends.go

@@ -51,6 +51,13 @@ func (svc *Service) SendFriendRequest(ctx context.Context, requesterID, addresse
 	if requesterID == addresseeID {
 		return ErrSelfRelation
 	}
+	// A guest cannot use friends — friends are a durable-account feature; the UI hides the
+	// flow, this is the server source of truth.
+	if acc, err := svc.accounts.GetByID(ctx, requesterID); err != nil {
+		return err
+	} else if acc.IsGuest {
+		return ErrGuestForbidden
+	}
 	iBlockThem, err := svc.store.blockExists(ctx, requesterID, addresseeID)
 	if err != nil {
 		return err

backend/internal/social/robotfriends.go

@@ -42,6 +42,12 @@ func (svc *Service) RequestInGame(ctx context.Context, requesterID, addresseeID,
 	if requesterID == addresseeID {
 		return ErrSelfRelation
 	}
+	// A guest cannot use friends: a durable-account feature (the UI hides it).
+	if acc, err := svc.accounts.GetByID(ctx, requesterID); err != nil {
+		return err
+	} else if acc.IsGuest {
+		return ErrGuestForbidden
+	}
 	isRobot, err := svc.accounts.IsRobot(ctx, addresseeID)
 	if err != nil {
 		return err

backend/internal/social/social.go

@@ -59,6 +59,9 @@ var (
 	// ErrRequestBlocked is returned when the addressee does not accept friend
 	// requests (their global toggle) or a block stands between the two accounts.
 	ErrRequestBlocked = errors.New("social: the addressee is not accepting friend requests")
+	// ErrGuestForbidden is returned when a guest attempts a durable-only action (send a friend
+	// request, redeem a friend code); friends are a durable-account feature.
+	ErrGuestForbidden = errors.New("social: guests cannot use friends")
 	// ErrRequestNotFound is returned when no pending friend request matches.
 	ErrRequestNotFound = errors.New("social: no pending friend request")
 	// ErrNoSharedGame is returned when a friend request targets someone the