refactor: remove persister abstraction layer

Inline persistence logic directly into game stores and handlers:
- game/persist.go: DB mapping methods on GameStore and GameInstance
- snake/persist.go: DB mapping methods on SnakeStore and SnakeGameInstance
- Chat persistence inlined into c4game handlers
- Delete db/persister.go (GamePersister, SnakePersister, ChatPersister)
- Stores now take *repository.Queries directly instead of Persister interface

db/persister.go

@@ -1,326 +0,0 @@
-package db
-
-import (
-	"context"
-	"database/sql"
-	"slices"
-
-	"github.com/ryanhamamura/c4/db/repository"
-	"github.com/ryanhamamura/c4/game"
-	"github.com/ryanhamamura/c4/snake"
-)
-
-type GamePersister struct {
-	queries *repository.Queries
-}
-
-func NewGamePersister(q *repository.Queries) *GamePersister {
-	return &GamePersister{queries: q}
-}
-
-func (p *GamePersister) SaveGame(g *game.Game) error {
-	ctx := context.Background()
-
-	_, err := p.queries.GetGame(ctx, g.ID)
-	if err == sql.ErrNoRows {
-		_, err = p.queries.CreateGame(ctx, repository.CreateGameParams{
-			ID:          g.ID,
-			Board:       g.BoardToJSON(),
-			CurrentTurn: int64(g.CurrentTurn),
-			Status:      int64(g.Status),
-		})
-		return err
-	}
-	if err != nil {
-		return err
-	}
-
-	var winnerUserID sql.NullString
-	if g.Winner != nil && g.Winner.UserID != nil {
-		winnerUserID = sql.NullString{String: *g.Winner.UserID, Valid: true}
-	}
-
-	winningCells := sql.NullString{}
-	if wc := g.WinningCellsToJSON(); wc != "" {
-		winningCells = sql.NullString{String: wc, Valid: true}
-	}
-
-	rematchGameID := sql.NullString{}
-	if g.RematchGameID != nil {
-		rematchGameID = sql.NullString{String: *g.RematchGameID, Valid: true}
-	}
-
-	return p.queries.UpdateGame(ctx, repository.UpdateGameParams{
-		Board:         g.BoardToJSON(),
-		CurrentTurn:   int64(g.CurrentTurn),
-		Status:        int64(g.Status),
-		WinnerUserID:  winnerUserID,
-		WinningCells:  winningCells,
-		RematchGameID: rematchGameID,
-		ID:            g.ID,
-	})
-}
-
-func (p *GamePersister) LoadGame(id string) (*game.Game, error) {
-	ctx := context.Background()
-	row, err := p.queries.GetGame(ctx, id)
-	if err != nil {
-		return nil, err
-	}
-
-	g := &game.Game{
-		ID:          row.ID,
-		CurrentTurn: int(row.CurrentTurn),
-		Status:      game.GameStatus(row.Status),
-	}
-
-	if err := g.BoardFromJSON(row.Board); err != nil {
-		return nil, err
-	}
-
-	if row.WinningCells.Valid {
-		g.WinningCellsFromJSON(row.WinningCells.String)
-	}
-
-	if row.RematchGameID.Valid {
-		g.RematchGameID = &row.RematchGameID.String
-	}
-
-	return g, nil
-}
-
-func (p *GamePersister) SaveGamePlayer(gameID string, player *game.Player, slot int) error {
-	ctx := context.Background()
-
-	var userID, guestPlayerID sql.NullString
-	if player.UserID != nil {
-		userID = sql.NullString{String: *player.UserID, Valid: true}
-	} else {
-		guestPlayerID = sql.NullString{String: string(player.ID), Valid: true}
-	}
-
-	return p.queries.CreateGamePlayer(ctx, repository.CreateGamePlayerParams{
-		GameID:        gameID,
-		UserID:        userID,
-		GuestPlayerID: guestPlayerID,
-		Nickname:      player.Nickname,
-		Color:         int64(player.Color),
-		Slot:          int64(slot),
-	})
-}
-
-func (p *GamePersister) LoadGamePlayers(gameID string) ([]*game.Player, error) {
-	ctx := context.Background()
-	rows, err := p.queries.GetGamePlayers(ctx, gameID)
-	if err != nil {
-		return nil, err
-	}
-
-	players := make([]*game.Player, 0, len(rows))
-	for _, row := range rows {
-		player := &game.Player{
-			Nickname: row.Nickname,
-			Color:    int(row.Color),
-		}
-
-		if row.UserID.Valid {
-			player.UserID = &row.UserID.String
-			player.ID = game.PlayerID(row.UserID.String)
-		} else if row.GuestPlayerID.Valid {
-			player.ID = game.PlayerID(row.GuestPlayerID.String)
-		}
-
-		players = append(players, player)
-	}
-
-	return players, nil
-}
-
-func (p *GamePersister) DeleteGame(id string) error {
-	ctx := context.Background()
-	return p.queries.DeleteGame(ctx, id)
-}
-
-// SnakePersister implements snake.Persister
-type SnakePersister struct {
-	queries *repository.Queries
-}
-
-func NewSnakePersister(q *repository.Queries) *SnakePersister {
-	return &SnakePersister{queries: q}
-}
-
-func (p *SnakePersister) SaveSnakeGame(sg *snake.SnakeGame) error {
-	ctx := context.Background()
-
-	boardJSON := "{}"
-	if sg.State != nil {
-		boardJSON = sg.State.ToJSON()
-	}
-
-	var gridWidth, gridHeight sql.NullInt64
-	if sg.State != nil {
-		gridWidth = sql.NullInt64{Int64: int64(sg.State.Width), Valid: true}
-		gridHeight = sql.NullInt64{Int64: int64(sg.State.Height), Valid: true}
-	}
-
-	_, err := p.queries.GetSnakeGame(ctx, sg.ID)
-	if err == sql.ErrNoRows {
-		_, err = p.queries.CreateSnakeGame(ctx, repository.CreateSnakeGameParams{
-			ID:         sg.ID,
-			Board:      boardJSON,
-			Status:     int64(sg.Status),
-			GridWidth:  gridWidth,
-			GridHeight: gridHeight,
-			GameMode:   int64(sg.Mode),
-			SnakeSpeed: int64(sg.Speed),
-		})
-		return err
-	}
-	if err != nil {
-		return err
-	}
-
-	var winnerUserID sql.NullString
-	if sg.Winner != nil && sg.Winner.UserID != nil {
-		winnerUserID = sql.NullString{String: *sg.Winner.UserID, Valid: true}
-	}
-
-	rematchGameID := sql.NullString{}
-	if sg.RematchGameID != nil {
-		rematchGameID = sql.NullString{String: *sg.RematchGameID, Valid: true}
-	}
-
-	return p.queries.UpdateSnakeGame(ctx, repository.UpdateSnakeGameParams{
-		Board:         boardJSON,
-		Status:        int64(sg.Status),
-		WinnerUserID:  winnerUserID,
-		RematchGameID: rematchGameID,
-		Score:         int64(sg.Score),
-		ID:            sg.ID,
-	})
-}
-
-func (p *SnakePersister) LoadSnakeGame(id string) (*snake.SnakeGame, error) {
-	ctx := context.Background()
-	row, err := p.queries.GetSnakeGame(ctx, id)
-	if err != nil {
-		return nil, err
-	}
-
-	state, err := snake.GameStateFromJSON(row.Board)
-	if err != nil {
-		state = &snake.GameState{}
-	}
-	if row.GridWidth.Valid {
-		state.Width = int(row.GridWidth.Int64)
-	}
-	if row.GridHeight.Valid {
-		state.Height = int(row.GridHeight.Int64)
-	}
-
-	sg := &snake.SnakeGame{
-		ID:      row.ID,
-		State:   state,
-		Players: make([]*snake.Player, 8),
-		Status:  snake.Status(row.Status),
-		Mode:    snake.GameMode(row.GameMode),
-		Score:   int(row.Score),
-		Speed:   int(row.SnakeSpeed),
-	}
-
-	if row.RematchGameID.Valid {
-		sg.RematchGameID = &row.RematchGameID.String
-	}
-
-	return sg, nil
-}
-
-func (p *SnakePersister) SaveSnakePlayer(gameID string, player *snake.Player) error {
-	ctx := context.Background()
-
-	var userID, guestPlayerID sql.NullString
-	if player.UserID != nil {
-		userID = sql.NullString{String: *player.UserID, Valid: true}
-	} else {
-		guestPlayerID = sql.NullString{String: string(player.ID), Valid: true}
-	}
-
-	return p.queries.CreateSnakePlayer(ctx, repository.CreateSnakePlayerParams{
-		GameID:        gameID,
-		UserID:        userID,
-		GuestPlayerID: guestPlayerID,
-		Nickname:      player.Nickname,
-		Color:         int64(player.Slot + 1),
-		Slot:          int64(player.Slot),
-	})
-}
-
-func (p *SnakePersister) LoadSnakePlayers(gameID string) ([]*snake.Player, error) {
-	ctx := context.Background()
-	rows, err := p.queries.GetSnakePlayers(ctx, gameID)
-	if err != nil {
-		return nil, err
-	}
-
-	players := make([]*snake.Player, 0, len(rows))
-	for _, row := range rows {
-		player := &snake.Player{
-			Nickname: row.Nickname,
-			Slot:     int(row.Slot),
-		}
-
-		if row.UserID.Valid {
-			player.UserID = &row.UserID.String
-			player.ID = snake.PlayerID(row.UserID.String)
-		} else if row.GuestPlayerID.Valid {
-			player.ID = snake.PlayerID(row.GuestPlayerID.String)
-		}
-
-		players = append(players, player)
-	}
-
-	return players, nil
-}
-
-func (p *SnakePersister) DeleteSnakeGame(id string) error {
-	ctx := context.Background()
-	return p.queries.DeleteSnakeGame(ctx, id)
-}
-
-type ChatPersister struct {
-	queries *repository.Queries
-}
-
-func NewChatPersister(q *repository.Queries) *ChatPersister {
-	return &ChatPersister{queries: q}
-}
-
-func (p *ChatPersister) SaveChatMessage(gameID string, msg game.ChatMessage) error {
-	return p.queries.CreateChatMessage(context.Background(), repository.CreateChatMessageParams{
-		GameID:    gameID,
-		Nickname:  msg.Nickname,
-		Color:     int64(msg.Color),
-		Message:   msg.Message,
-		CreatedAt: msg.Time,
-	})
-}
-
-func (p *ChatPersister) LoadChatMessages(gameID string) ([]game.ChatMessage, error) {
-	rows, err := p.queries.GetChatMessages(context.Background(), gameID)
-	if err != nil {
-		return nil, err
-	}
-	msgs := make([]game.ChatMessage, len(rows))
-	for i, r := range rows {
-		msgs[i] = game.ChatMessage{
-			Nickname: r.Nickname,
-			Color:    int(r.Color),
-			Message:  r.Message,
-			Time:     r.CreatedAt,
-		}
-	}
-	// Query returns newest-first; reverse to oldest-first for display
-	slices.Reverse(msgs)
-	return msgs, nil
-}

features/c4game/handlers.go

@@ -1,8 +1,10 @@
 package c4game
 
 import (
+	"context"
 	"encoding/json"
 	"net/http"
+	"slices"
 	"strconv"
 	"sync"
 	"time"
@@ -10,14 +12,14 @@ import (
 	"github.com/alexedwards/scs/v2"
 	"github.com/go-chi/chi/v5"
 	"github.com/nats-io/nats.go"
-	"github.com/ryanhamamura/c4/db"
+	"github.com/ryanhamamura/c4/db/repository"
 	"github.com/ryanhamamura/c4/features/c4game/components"
 	"github.com/ryanhamamura/c4/features/c4game/pages"
 	"github.com/ryanhamamura/c4/game"
 	"github.com/starfederation/datastar-go/datastar"
 )
 
-func HandleGamePage(store *game.GameStore, sessions *scs.SessionManager, chatPersister *db.ChatPersister) http.HandlerFunc {
+func HandleGamePage(store *game.GameStore, sessions *scs.SessionManager, queries *repository.Queries) http.HandlerFunc {
 	return func(w http.ResponseWriter, r *http.Request) {
 		gameID := chi.URLParam(r, "game_id")
 
@@ -73,8 +75,8 @@ func HandleGamePage(store *game.GameStore, sessions *scs.SessionManager, chatPer
 
 		// Player is in the game — render full game page
 		g := gi.GetGame()
-		uiMsgs, _ := chatPersister.LoadChatMessages(gameID)
+		chatMsgs := loadChatMessages(queries, gameID)
-		msgs := uiChatToComponents(uiMsgs)
+		msgs := chatToComponents(chatMsgs)
 
 		if err := pages.GamePage(g, myColor, msgs).Render(r.Context(), w); err != nil {
 			http.Error(w, http.StatusText(http.StatusInternalServerError), http.StatusInternalServerError)
@@ -82,7 +84,7 @@ func HandleGamePage(store *game.GameStore, sessions *scs.SessionManager, chatPer
 	}
 }
 
-func HandleGameEvents(store *game.GameStore, nc *nats.Conn, sessions *scs.SessionManager, chatPersister *db.ChatPersister) http.HandlerFunc {
+func HandleGameEvents(store *game.GameStore, nc *nats.Conn, sessions *scs.SessionManager, queries *repository.Queries) http.HandlerFunc {
 	return func(w http.ResponseWriter, r *http.Request) {
 		gameID := chi.URLParam(r, "game_id")
 
@@ -103,9 +105,9 @@ func HandleGameEvents(store *game.GameStore, nc *nats.Conn, sessions *scs.Sessio
 		sse := datastar.NewSSE(w, r)
 
 		// Load initial chat messages
-		uiMsgs, _ := chatPersister.LoadChatMessages(gameID)
+		chatMsgs := loadChatMessages(queries, gameID)
 		var chatMu sync.Mutex
-		chatMessages := uiChatToComponents(uiMsgs)
+		chatMessages := chatToComponents(chatMsgs)
 
 		// Send initial render of all components
 		sendGameComponents(sse, gi, myColor, chatMessages, &chatMu, gameID)
@@ -203,7 +205,7 @@ func HandleDropPiece(store *game.GameStore, sessions *scs.SessionManager) http.H
 	}
 }
 
-func HandleSendChat(store *game.GameStore, nc *nats.Conn, sessions *scs.SessionManager, chatPersister *db.ChatPersister) http.HandlerFunc {
+func HandleSendChat(store *game.GameStore, nc *nats.Conn, sessions *scs.SessionManager, queries *repository.Queries) http.HandlerFunc {
 	return func(w http.ResponseWriter, r *http.Request) {
 		gameID := chi.URLParam(r, "game_id")
 
@@ -254,7 +256,7 @@ func HandleSendChat(store *game.GameStore, nc *nats.Conn, sessions *scs.SessionM
 			Message:  signals.ChatMsg,
 			Time:     time.Now().UnixMilli(),
 		}
-		chatPersister.SaveChatMessage(gameID, cm)
+		saveChatMessage(queries, gameID, cm)
 
 		data, err := json.Marshal(cm)
 		if err != nil {
@@ -353,10 +355,40 @@ func sendGameComponents(sse *datastar.ServerSentEventGenerator, gi *game.GameIns
 	sse.PatchElementTempl(components.Chat(msgs, gameID), datastar.WithSelectorID("c4-chat")) //nolint:errcheck
 }
 
-// uiChatToComponents converts ui.C4ChatMessage slice to components.ChatMessage slice.
+// Chat persistence helpers — inlined from the former ChatPersister.
-func uiChatToComponents(uiMsgs []game.ChatMessage) []components.ChatMessage {
+
-	msgs := make([]components.ChatMessage, len(uiMsgs))
+func saveChatMessage(queries *repository.Queries, gameID string, msg game.ChatMessage) {
-	for i, m := range uiMsgs {
+	queries.CreateChatMessage(context.Background(), repository.CreateChatMessageParams{ //nolint:errcheck
+		GameID:    gameID,
+		Nickname:  msg.Nickname,
+		Color:     int64(msg.Color),
+		Message:   msg.Message,
+		CreatedAt: msg.Time,
+	})
+}
+
+func loadChatMessages(queries *repository.Queries, gameID string) []game.ChatMessage {
+	rows, err := queries.GetChatMessages(context.Background(), gameID)
+	if err != nil {
+		return nil
+	}
+	msgs := make([]game.ChatMessage, len(rows))
+	for i, r := range rows {
+		msgs[i] = game.ChatMessage{
+			Nickname: r.Nickname,
+			Color:    int(r.Color),
+			Message:  r.Message,
+			Time:     r.CreatedAt,
+		}
+	}
+	// DB returns newest-first; reverse for display
+	slices.Reverse(msgs)
+	return msgs
+}
+
+func chatToComponents(chatMsgs []game.ChatMessage) []components.ChatMessage {
+	msgs := make([]components.ChatMessage, len(chatMsgs))
+	for i, m := range chatMsgs {
 		msgs[i] = components.ChatMessage{
 			Nickname: m.Nickname,
 			Color:    m.Color,

features/c4game/routes.go

@@ -4,7 +4,7 @@ import (
 	"github.com/alexedwards/scs/v2"
 	"github.com/go-chi/chi/v5"
 	"github.com/nats-io/nats.go"
-	"github.com/ryanhamamura/c4/db"
+	"github.com/ryanhamamura/c4/db/repository"
 	"github.com/ryanhamamura/c4/game"
 )
 
@@ -13,14 +13,14 @@ func SetupRoutes(
 	store *game.GameStore,
 	nc *nats.Conn,
 	sessions *scs.SessionManager,
-	chatPersister *db.ChatPersister,
+	queries *repository.Queries,
 ) error {
-	router.Get("/game/{game_id}", HandleGamePage(store, sessions, chatPersister))
+	router.Get("/game/{game_id}", HandleGamePage(store, sessions, queries))
-	router.Get("/game/{game_id}/events", HandleGameEvents(store, nc, sessions, chatPersister))
+	router.Get("/game/{game_id}/events", HandleGameEvents(store, nc, sessions, queries))
 
 	router.Route("/api/game/{game_id}", func(r chi.Router) {
 		r.Post("/drop", HandleDropPiece(store, sessions))
-		r.Post("/chat", HandleSendChat(store, nc, sessions, chatPersister))
+		r.Post("/chat", HandleSendChat(store, nc, sessions, queries))
 		r.Post("/join", HandleSetNickname(store, sessions))
 		r.Post("/rematch", HandleRematch(store, sessions))
 	})

game/persist.go

@@ -0,0 +1,157 @@
+package game
+
+import (
+	"context"
+	"database/sql"
+
+	"github.com/ryanhamamura/c4/db/repository"
+)
+
+// Persistence methods on GameStore (used during Get to hydrate from DB).
+
+func (gs *GameStore) saveGame(g *Game) error {
+	ctx := context.Background()
+
+	_, err := gs.queries.GetGame(ctx, g.ID)
+	if err == sql.ErrNoRows {
+		_, err = gs.queries.CreateGame(ctx, repository.CreateGameParams{
+			ID:          g.ID,
+			Board:       g.BoardToJSON(),
+			CurrentTurn: int64(g.CurrentTurn),
+			Status:      int64(g.Status),
+		})
+		return err
+	}
+	if err != nil {
+		return err
+	}
+
+	return gs.queries.UpdateGame(ctx, updateGameParams(g))
+}
+
+func (gs *GameStore) loadGame(id string) (*Game, error) {
+	row, err := gs.queries.GetGame(context.Background(), id)
+	if err != nil {
+		return nil, err
+	}
+	return gameFromRow(row)
+}
+
+func (gs *GameStore) loadGamePlayers(id string) ([]*Player, error) {
+	rows, err := gs.queries.GetGamePlayers(context.Background(), id)
+	if err != nil {
+		return nil, err
+	}
+	return playersFromRows(rows), nil
+}
+
+// Persistence methods on GameInstance (used during gameplay mutations).
+
+func (gi *GameInstance) saveGame(g *Game) error {
+	ctx := context.Background()
+
+	_, err := gi.queries.GetGame(ctx, g.ID)
+	if err == sql.ErrNoRows {
+		_, err = gi.queries.CreateGame(ctx, repository.CreateGameParams{
+			ID:          g.ID,
+			Board:       g.BoardToJSON(),
+			CurrentTurn: int64(g.CurrentTurn),
+			Status:      int64(g.Status),
+		})
+		return err
+	}
+	if err != nil {
+		return err
+	}
+
+	return gi.queries.UpdateGame(ctx, updateGameParams(g))
+}
+
+func (gi *GameInstance) saveGamePlayer(gameID string, player *Player, slot int) error {
+	var userID, guestPlayerID sql.NullString
+	if player.UserID != nil {
+		userID = sql.NullString{String: *player.UserID, Valid: true}
+	} else {
+		guestPlayerID = sql.NullString{String: string(player.ID), Valid: true}
+	}
+
+	return gi.queries.CreateGamePlayer(context.Background(), repository.CreateGamePlayerParams{
+		GameID:        gameID,
+		UserID:        userID,
+		GuestPlayerID: guestPlayerID,
+		Nickname:      player.Nickname,
+		Color:         int64(player.Color),
+		Slot:          int64(slot),
+	})
+}
+
+// Shared helpers for domain ↔ DB mapping.
+
+func updateGameParams(g *Game) repository.UpdateGameParams {
+	var winnerUserID sql.NullString
+	if g.Winner != nil && g.Winner.UserID != nil {
+		winnerUserID = sql.NullString{String: *g.Winner.UserID, Valid: true}
+	}
+
+	var winningCells sql.NullString
+	if wc := g.WinningCellsToJSON(); wc != "" {
+		winningCells = sql.NullString{String: wc, Valid: true}
+	}
+
+	var rematchGameID sql.NullString
+	if g.RematchGameID != nil {
+		rematchGameID = sql.NullString{String: *g.RematchGameID, Valid: true}
+	}
+
+	return repository.UpdateGameParams{
+		Board:         g.BoardToJSON(),
+		CurrentTurn:   int64(g.CurrentTurn),
+		Status:        int64(g.Status),
+		WinnerUserID:  winnerUserID,
+		WinningCells:  winningCells,
+		RematchGameID: rematchGameID,
+		ID:            g.ID,
+	}
+}
+
+func gameFromRow(row repository.Game) (*Game, error) {
+	g := &Game{
+		ID:          row.ID,
+		CurrentTurn: int(row.CurrentTurn),
+		Status:      GameStatus(row.Status),
+	}
+
+	if err := g.BoardFromJSON(row.Board); err != nil {
+		return nil, err
+	}
+
+	if row.WinningCells.Valid {
+		g.WinningCellsFromJSON(row.WinningCells.String)
+	}
+
+	if row.RematchGameID.Valid {
+		g.RematchGameID = &row.RematchGameID.String
+	}
+
+	return g, nil
+}
+
+func playersFromRows(rows []repository.GamePlayer) []*Player {
+	players := make([]*Player, 0, len(rows))
+	for _, row := range rows {
+		player := &Player{
+			Nickname: row.Nickname,
+			Color:    int(row.Color),
+		}
+
+		if row.UserID.Valid {
+			player.UserID = &row.UserID.String
+			player.ID = PlayerID(row.UserID.String)
+		} else if row.GuestPlayerID.Valid {
+			player.ID = PlayerID(row.GuestPlayerID.String)
+		}
+
+		players = append(players, player)
+	}
+	return players
+}

game/store.go

@@ -1,40 +1,32 @@
 package game
 
 import (
+	"context"
 	"crypto/rand"
 	"encoding/hex"
 	"sync"
+
+	"github.com/ryanhamamura/c4/db/repository"
 )
 
 type PlayerSession struct {
 	Player *Player
 }
 
-type Persister interface {
-	SaveGame(g *Game) error
-	LoadGame(id string) (*Game, error)
-	SaveGamePlayer(gameID string, player *Player, slot int) error
-	LoadGamePlayers(gameID string) ([]*Player, error)
-	DeleteGame(id string) error
-}
-
 type GameStore struct {
 	games      map[string]*GameInstance
 	gamesMu    sync.RWMutex
-	persister  Persister
+	queries    *repository.Queries
 	notifyFunc func(gameID string)
 }
 
-func NewGameStore() *GameStore {
+func NewGameStore(queries *repository.Queries) *GameStore {
 	return &GameStore{
 		games:   make(map[string]*GameInstance),
+		queries: queries,
 	}
 }
 
-func (gs *GameStore) SetPersister(p Persister) {
-	gs.persister = p
-}
-
 func (gs *GameStore) SetNotifyFunc(f func(gameID string)) {
 	gs.notifyFunc = f
 }
@@ -50,14 +42,14 @@ func (gs *GameStore) makeNotify(gameID string) func() {
 func (gs *GameStore) Create() *GameInstance {
 	id := GenerateID(4)
 	gi := NewGameInstance(id)
-	gi.persister = gs.persister
+	gi.queries = gs.queries
 	gi.notify = gs.makeNotify(id)
 	gs.gamesMu.Lock()
 	gs.games[id] = gi
 	gs.gamesMu.Unlock()
 
-	if gs.persister != nil {
+	if gs.queries != nil {
-		gs.persister.SaveGame(gi.game)
+		gs.saveGame(gi.game)
 	}
 
 	return gi
@@ -72,27 +64,27 @@ func (gs *GameStore) Get(id string) (*GameInstance, bool) {
 		return gi, true
 	}
 
-	if gs.persister == nil {
+	if gs.queries == nil {
 		return nil, false
 	}
 
-	game, err := gs.persister.LoadGame(id)
+	g, err := gs.loadGame(id)
-	if err != nil || game == nil {
+	if err != nil || g == nil {
 		return nil, false
 	}
 
-	players, _ := gs.persister.LoadGamePlayers(id)
+	players, _ := gs.loadGamePlayers(id)
 	for _, p := range players {
 		if p.Color == 1 {
-			game.Players[0] = p
+			g.Players[0] = p
 		} else if p.Color == 2 {
-			game.Players[1] = p
+			g.Players[1] = p
 		}
 	}
 
 	gi = &GameInstance{
-		game:      game,
+		game:    g,
-		persister: gs.persister,
+		queries: gs.queries,
 		notify:  gs.makeNotify(id),
 	}
 
@@ -108,8 +100,8 @@ func (gs *GameStore) Delete(id string) error {
 	delete(gs.games, id)
 	gs.gamesMu.Unlock()
 
-	if gs.persister != nil {
+	if gs.queries != nil {
-		return gs.persister.DeleteGame(id)
+		return gs.queries.DeleteGame(context.Background(), id)
 	}
 	return nil
 }
@@ -124,7 +116,7 @@ type GameInstance struct {
 	game    *Game
 	gameMu  sync.RWMutex
 	notify  func()
-	persister Persister
+	queries *repository.Queries
 }
 
 func NewGameInstance(id string) *GameInstance {
@@ -158,9 +150,9 @@ func (gi *GameInstance) Join(ps *PlayerSession) bool {
 		return false
 	}
 
-	if gi.persister != nil {
+	if gi.queries != nil {
-		gi.persister.SaveGamePlayer(gi.game.ID, ps.Player, slot)
+		gi.saveGamePlayer(gi.game.ID, ps.Player, slot)
-		gi.persister.SaveGame(gi.game)
+		gi.saveGame(gi.game)
 	}
 
 	gi.notify()
@@ -196,8 +188,8 @@ func (gi *GameInstance) CreateRematch(gs *GameStore) *GameInstance {
 	newID := newGI.ID()
 	gi.game.RematchGameID = &newID
 
-	if gi.persister != nil {
+	if gi.queries != nil {
-		if err := gi.persister.SaveGame(gi.game); err != nil {
+		if err := gi.saveGame(gi.game); err != nil {
 			gs.Delete(newID)
 			gi.game.RematchGameID = nil
 			return nil
@@ -230,8 +222,8 @@ func (gi *GameInstance) DropPiece(col int, playerColor int) bool {
 		gi.game.SwitchTurn()
 	}
 
-	if gi.persister != nil {
+	if gi.queries != nil {
-		gi.persister.SaveGame(gi.game)
+		gi.saveGame(gi.game)
 	}
 
 	gi.notify()

main.go

@@ -71,20 +71,16 @@ func run(ctx context.Context) error {
 	defer cleanupNATS()
 
 	// Game stores
-	store := game.NewGameStore()
+	store := game.NewGameStore(queries)
-	store.SetPersister(db.NewGamePersister(queries))
 	store.SetNotifyFunc(func(gameID string) {
 		nc.Publish("game."+gameID, nil) //nolint:errcheck // best-effort notification
 	})
 
-	snakeStore := snake.NewSnakeStore()
+	snakeStore := snake.NewSnakeStore(queries)
-	snakeStore.SetPersister(db.NewSnakePersister(queries))
 	snakeStore.SetNotifyFunc(func(gameID string) {
 		nc.Publish("snake."+gameID, nil) //nolint:errcheck // best-effort notification
 	})
 
-	chatPersister := db.NewChatPersister(queries)
-
 	// Router
 	logger := log.Logger
 	r := chi.NewMux()
@@ -94,7 +90,7 @@ func run(ctx context.Context) error {
 		sessionManager.LoadAndSave,
 	)
 
-	if err := router.SetupRoutes(r, queries, sessionManager, nc, store, snakeStore, chatPersister, assets); err != nil {
+	if err := router.SetupRoutes(r, queries, sessionManager, nc, store, snakeStore, assets); err != nil {
 		return fmt.Errorf("setting up routes: %w", err)
 	}
 

router/router.go

@@ -8,7 +8,6 @@ import (
 	"sync"
 
 	"github.com/ryanhamamura/c4/config"
-	"github.com/ryanhamamura/c4/db"
 	"github.com/ryanhamamura/c4/db/repository"
 	"github.com/ryanhamamura/c4/features/auth"
 	"github.com/ryanhamamura/c4/features/c4game"
@@ -30,7 +29,6 @@ func SetupRoutes(
 	nc *nats.Conn,
 	store *game.GameStore,
 	snakeStore *snake.SnakeStore,
-	chatPersister *db.ChatPersister,
 	assets embed.FS,
 ) error {
 	// Static assets
@@ -44,7 +42,7 @@ func SetupRoutes(
 
 	auth.SetupRoutes(router, queries, sessions)
 	lobby.SetupRoutes(router, queries, sessions, store, snakeStore)
-	c4game.SetupRoutes(router, store, nc, sessions, chatPersister)
+	c4game.SetupRoutes(router, store, nc, sessions, queries)
 	snakegame.SetupRoutes(router, snakeStore, nc, sessions)
 
 	return nil

snake/loop.go

@@ -61,16 +61,16 @@ func (si *SnakeGameInstance) countdownPhase() {
 				si.initGame()
 				si.game.Status = StatusInProgress
 
-				if si.persister != nil {
+				if si.queries != nil {
-					si.persister.SaveSnakeGame(si.game)
+					si.saveSnakeGame(si.game)
 				}
 				si.gameMu.Unlock()
 				si.notify()
 				return
 			}
 
-			if si.persister != nil {
+			if si.queries != nil {
-				si.persister.SaveSnakeGame(si.game)
+				si.saveSnakeGame(si.game)
 			}
 			si.gameMu.Unlock()
 			si.notify()
@@ -123,8 +123,8 @@ func (si *SnakeGameInstance) gamePhase() {
 			// Inactivity timeout
 			if time.Since(lastInput) > inactivityLimit {
 				si.game.Status = StatusFinished
-				if si.persister != nil {
+				if si.queries != nil {
-					si.persister.SaveSnakeGame(si.game)
+					si.saveSnakeGame(si.game)
 				}
 				si.gameMu.Unlock()
 				si.notify()
@@ -195,8 +195,8 @@ func (si *SnakeGameInstance) gamePhase() {
 				si.game.Status = StatusFinished
 			}
 
-			if si.persister != nil {
+			if si.queries != nil {
-				si.persister.SaveSnakeGame(si.game)
+				si.saveSnakeGame(si.game)
 			}
 
 			si.gameMu.Unlock()

snake/persist.go

@@ -0,0 +1,186 @@
+package snake
+
+import (
+	"context"
+	"database/sql"
+
+	"github.com/ryanhamamura/c4/db/repository"
+)
+
+// Persistence methods on SnakeStore (used during Get to hydrate from DB).
+
+func (ss *SnakeStore) saveSnakeGame(sg *SnakeGame) error {
+	ctx := context.Background()
+
+	boardJSON := "{}"
+	if sg.State != nil {
+		boardJSON = sg.State.ToJSON()
+	}
+
+	var gridWidth, gridHeight sql.NullInt64
+	if sg.State != nil {
+		gridWidth = sql.NullInt64{Int64: int64(sg.State.Width), Valid: true}
+		gridHeight = sql.NullInt64{Int64: int64(sg.State.Height), Valid: true}
+	}
+
+	_, err := ss.queries.GetSnakeGame(ctx, sg.ID)
+	if err == sql.ErrNoRows {
+		_, err = ss.queries.CreateSnakeGame(ctx, repository.CreateSnakeGameParams{
+			ID:         sg.ID,
+			Board:      boardJSON,
+			Status:     int64(sg.Status),
+			GridWidth:  gridWidth,
+			GridHeight: gridHeight,
+			GameMode:   int64(sg.Mode),
+			SnakeSpeed: int64(sg.Speed),
+		})
+		return err
+	}
+	if err != nil {
+		return err
+	}
+
+	return ss.queries.UpdateSnakeGame(ctx, updateSnakeGameParams(sg, boardJSON))
+}
+
+func (ss *SnakeStore) loadSnakeGame(id string) (*SnakeGame, error) {
+	row, err := ss.queries.GetSnakeGame(context.Background(), id)
+	if err != nil {
+		return nil, err
+	}
+	return snakeGameFromRow(row)
+}
+
+func (ss *SnakeStore) loadSnakePlayers(id string) ([]*Player, error) {
+	rows, err := ss.queries.GetSnakePlayers(context.Background(), id)
+	if err != nil {
+		return nil, err
+	}
+	return snakePlayersFromRows(rows), nil
+}
+
+// Persistence methods on SnakeGameInstance (used during gameplay mutations).
+
+func (si *SnakeGameInstance) saveSnakeGame(sg *SnakeGame) error {
+	ctx := context.Background()
+
+	boardJSON := "{}"
+	if sg.State != nil {
+		boardJSON = sg.State.ToJSON()
+	}
+
+	var gridWidth, gridHeight sql.NullInt64
+	if sg.State != nil {
+		gridWidth = sql.NullInt64{Int64: int64(sg.State.Width), Valid: true}
+		gridHeight = sql.NullInt64{Int64: int64(sg.State.Height), Valid: true}
+	}
+
+	_, err := si.queries.GetSnakeGame(ctx, sg.ID)
+	if err == sql.ErrNoRows {
+		_, err = si.queries.CreateSnakeGame(ctx, repository.CreateSnakeGameParams{
+			ID:         sg.ID,
+			Board:      boardJSON,
+			Status:     int64(sg.Status),
+			GridWidth:  gridWidth,
+			GridHeight: gridHeight,
+			GameMode:   int64(sg.Mode),
+			SnakeSpeed: int64(sg.Speed),
+		})
+		return err
+	}
+	if err != nil {
+		return err
+	}
+
+	return si.queries.UpdateSnakeGame(ctx, updateSnakeGameParams(sg, boardJSON))
+}
+
+func (si *SnakeGameInstance) saveSnakePlayer(gameID string, player *Player) error {
+	var userID, guestPlayerID sql.NullString
+	if player.UserID != nil {
+		userID = sql.NullString{String: *player.UserID, Valid: true}
+	} else {
+		guestPlayerID = sql.NullString{String: string(player.ID), Valid: true}
+	}
+
+	return si.queries.CreateSnakePlayer(context.Background(), repository.CreateSnakePlayerParams{
+		GameID:        gameID,
+		UserID:        userID,
+		GuestPlayerID: guestPlayerID,
+		Nickname:      player.Nickname,
+		Color:         int64(player.Slot + 1),
+		Slot:          int64(player.Slot),
+	})
+}
+
+// Shared helpers for domain ↔ DB mapping.
+
+func updateSnakeGameParams(sg *SnakeGame, boardJSON string) repository.UpdateSnakeGameParams {
+	var winnerUserID sql.NullString
+	if sg.Winner != nil && sg.Winner.UserID != nil {
+		winnerUserID = sql.NullString{String: *sg.Winner.UserID, Valid: true}
+	}
+
+	var rematchGameID sql.NullString
+	if sg.RematchGameID != nil {
+		rematchGameID = sql.NullString{String: *sg.RematchGameID, Valid: true}
+	}
+
+	return repository.UpdateSnakeGameParams{
+		Board:         boardJSON,
+		Status:        int64(sg.Status),
+		WinnerUserID:  winnerUserID,
+		RematchGameID: rematchGameID,
+		Score:         int64(sg.Score),
+		ID:            sg.ID,
+	}
+}
+
+func snakeGameFromRow(row repository.Game) (*SnakeGame, error) {
+	state, err := GameStateFromJSON(row.Board)
+	if err != nil {
+		state = &GameState{}
+	}
+	if row.GridWidth.Valid {
+		state.Width = int(row.GridWidth.Int64)
+	}
+	if row.GridHeight.Valid {
+		state.Height = int(row.GridHeight.Int64)
+	}
+
+	sg := &SnakeGame{
+		ID:      row.ID,
+		State:   state,
+		Players: make([]*Player, 8),
+		Status:  Status(row.Status),
+		Mode:    GameMode(row.GameMode),
+		Score:   int(row.Score),
+		Speed:   int(row.SnakeSpeed),
+	}
+
+	if row.RematchGameID.Valid {
+		sg.RematchGameID = &row.RematchGameID.String
+	}
+
+	return sg, nil
+}
+
+func snakePlayersFromRows(rows []repository.GamePlayer) []*Player {
+	players := make([]*Player, 0, len(rows))
+	for _, row := range rows {
+		player := &Player{
+			Nickname: row.Nickname,
+			Slot:     int(row.Slot),
+		}
+
+		if row.UserID.Valid {
+			player.UserID = &row.UserID.String
+			player.ID = PlayerID(row.UserID.String)
+		} else if row.GuestPlayerID.Valid {
+			player.ID = PlayerID(row.GuestPlayerID.String)
+		}
+
+		players = append(players, player)
+	}
+	return players
+}

snake/store.go

@@ -1,36 +1,28 @@
 package snake
 
 import (
+	"context"
 	"crypto/rand"
 	"encoding/hex"
 	"sync"
-)
 
-type Persister interface {
+	"github.com/ryanhamamura/c4/db/repository"
-	SaveSnakeGame(sg *SnakeGame) error
+)
-	LoadSnakeGame(id string) (*SnakeGame, error)
-	SaveSnakePlayer(gameID string, player *Player) error
-	LoadSnakePlayers(gameID string) ([]*Player, error)
-	DeleteSnakeGame(id string) error
-}
 
 type SnakeStore struct {
 	games      map[string]*SnakeGameInstance
 	gamesMu    sync.RWMutex
-	persister  Persister
+	queries    *repository.Queries
 	notifyFunc func(gameID string)
 }
 
-func NewSnakeStore() *SnakeStore {
+func NewSnakeStore(queries *repository.Queries) *SnakeStore {
 	return &SnakeStore{
 		games:   make(map[string]*SnakeGameInstance),
+		queries: queries,
 	}
 }
 
-func (ss *SnakeStore) SetPersister(p Persister) {
-	ss.persister = p
-}
-
 func (ss *SnakeStore) SetNotifyFunc(f func(gameID string)) {
 	ss.notifyFunc = f
 }
@@ -62,7 +54,7 @@ func (ss *SnakeStore) Create(width, height int, mode GameMode, speed int) *Snake
 	si := &SnakeGameInstance{
 		game:    sg,
 		notify:  ss.makeNotify(id),
-		persister: ss.persister,
+		queries: ss.queries,
 		store:   ss,
 	}
 
@@ -70,8 +62,8 @@ func (ss *SnakeStore) Create(width, height int, mode GameMode, speed int) *Snake
 	ss.games[id] = si
 	ss.gamesMu.Unlock()
 
-	if ss.persister != nil {
+	if ss.queries != nil {
-		ss.persister.SaveSnakeGame(sg)
+		ss.saveSnakeGame(sg)
 	}
 
 	return si
@@ -86,16 +78,16 @@ func (ss *SnakeStore) Get(id string) (*SnakeGameInstance, bool) {
 		return si, true
 	}
 
-	if ss.persister == nil {
+	if ss.queries == nil {
 		return nil, false
 	}
 
-	sg, err := ss.persister.LoadSnakeGame(id)
+	sg, err := ss.loadSnakeGame(id)
 	if err != nil || sg == nil {
 		return nil, false
 	}
 
-	players, _ := ss.persister.LoadSnakePlayers(id)
+	players, _ := ss.loadSnakePlayers(id)
 	if sg.Players == nil {
 		sg.Players = make([]*Player, 8)
 	}
@@ -108,7 +100,7 @@ func (ss *SnakeStore) Get(id string) (*SnakeGameInstance, bool) {
 	si = &SnakeGameInstance{
 		game:    sg,
 		notify:  ss.makeNotify(id),
-		persister: ss.persister,
+		queries: ss.queries,
 		store:   ss,
 	}
 
@@ -129,8 +121,8 @@ func (ss *SnakeStore) Delete(id string) error {
 		si.Stop()
 	}
 
-	if ss.persister != nil {
+	if ss.queries != nil {
-		return ss.persister.DeleteSnakeGame(id)
+		return ss.queries.DeleteSnakeGame(context.Background(), id)
 	}
 	return nil
 }
@@ -162,7 +154,7 @@ type SnakeGameInstance struct {
 	gameMu          sync.RWMutex
 	pendingDirQueue [8][]Direction // queued directions per slot (max 3)
 	notify          func()
-	persister      Persister
+	queries         *repository.Queries
 	store           *SnakeStore
 	stopCh          chan struct{}
 	loopOnce        sync.Once
@@ -214,9 +206,9 @@ func (si *SnakeGameInstance) Join(player *Player) bool {
 	player.Slot = slot
 	si.game.Players[slot] = player
 
-	if si.persister != nil {
+	if si.queries != nil {
-		si.persister.SaveSnakePlayer(si.game.ID, player)
+		si.saveSnakePlayer(si.game.ID, player)
-		si.persister.SaveSnakeGame(si.game)
+		si.saveSnakeGame(si.game)
 	}
 
 	si.notify()
@@ -301,8 +293,8 @@ func (si *SnakeGameInstance) CreateRematch() *SnakeGameInstance {
 	}
 	si.game.RematchGameID = &newID
 
-	if si.persister != nil {
+	if si.queries != nil {
-		si.persister.SaveSnakeGame(si.game)
+		si.saveSnakeGame(si.game)
 	}
 	si.gameMu.Unlock()