diff --git a/cmd/buyandhold/main.go b/cmd/buyandhold/main.go
new file mode 100644
index 000000000..07f9ace1b
--- /dev/null
+++ b/cmd/buyandhold/main.go
@@ -0,0 +1,84 @@
+package buyandhold
+
+import (
+	"context"
+	"fmt"
+	"syscall"
+
+	"github.com/jmoiron/sqlx"
+	log "github.com/sirupsen/logrus"
+	"github.com/spf13/cobra"
+	"github.com/spf13/viper"
+
+	"github.com/c9s/bbgo/cmd/cmdutil"
+	"github.com/c9s/bbgo/pkg/bbgo"
+	"github.com/c9s/bbgo/pkg/strategy/buyandhold"
+	"github.com/c9s/bbgo/pkg/types"
+)
+
+func init() {
+	rootCmd.Flags().String("exchange", "", "target exchange")
+	rootCmd.Flags().String("symbol", "", "trading symbol")
+}
+
+func connectMysql() (*sqlx.DB, error) {
+	mysqlURL := viper.GetString("mysql-url")
+	mysqlURL = fmt.Sprintf("%s?parseTime=true", mysqlURL)
+	return sqlx.Connect("mysql", mysqlURL)
+}
+
+var rootCmd = &cobra.Command{
+	Use:   "buyandhold",
+	Short: "buy and hold",
+	Long:  "hold trader",
+
+	// SilenceUsage is an option to silence usage when an error occurs.
+	SilenceUsage: true,
+
+	RunE: func(cmd *cobra.Command, args []string) error {
+		ctx, cancel := context.WithCancel(context.Background())
+		defer cancel()
+
+		exchangeNameStr, err := cmd.Flags().GetString("exchange")
+		if err != nil {
+			return err
+		}
+
+		exchangeName, err := types.ValidExchangeName(exchangeNameStr)
+		if err != nil {
+			return err
+		}
+
+		symbol, err := cmd.Flags().GetString("symbol")
+		if err != nil {
+			return err
+		}
+
+		exchange, err := cmdutil.NewExchange(exchangeName)
+		if err != nil {
+			return err
+		}
+
+		db, err := cmdutil.ConnectMySQL()
+		if err != nil {
+			return err
+		}
+
+		sessionID := "main"
+		environ := bbgo.NewEnvironment(db)
+		environ.AddExchange(sessionID, exchange).Subscribe(types.KLineChannel, symbol, types.SubscribeOptions{})
+
+		trader := bbgo.NewTrader(environ)
+		trader.AttachStrategy(sessionID, buyandhold.New(symbol))
+		trader.Run(ctx)
+
+		cmdutil.WaitForSignal(ctx, syscall.SIGINT, syscall.SIGTERM)
+		return nil
+	},
+}
+
+func main() {
+	if err := rootCmd.Execute(); err != nil {
+		log.WithError(err).Fatalf("cannot execute command")
+	}
+}
diff --git a/cmd/cmdutil/db.go b/cmd/cmdutil/db.go
new file mode 100644
index 000000000..f50c3f7f2
--- /dev/null
+++ b/cmd/cmdutil/db.go
@@ -0,0 +1,14 @@
+package cmdutil
+
+import (
+	"fmt"
+
+	"github.com/jmoiron/sqlx"
+	"github.com/spf13/viper"
+)
+
+func ConnectMySQL() (*sqlx.DB, error) {
+	mysqlURL := viper.GetString("mysql-url")
+	mysqlURL = fmt.Sprintf("%s?parseTime=true", mysqlURL)
+	return sqlx.Connect("mysql", mysqlURL)
+}
diff --git a/cmd/cmdutil/exchange.go b/cmd/cmdutil/exchange.go
new file mode 100644
index 000000000..926690406
--- /dev/null
+++ b/cmd/cmdutil/exchange.go
@@ -0,0 +1,36 @@
+package cmdutil
+
+import (
+	"github.com/pkg/errors"
+	"github.com/spf13/viper"
+
+	"github.com/c9s/bbgo/pkg/exchange/binance"
+	"github.com/c9s/bbgo/pkg/exchange/max"
+	"github.com/c9s/bbgo/pkg/types"
+)
+
+func NewExchange(n types.ExchangeName) (types.Exchange, error) {
+	switch n {
+
+	case types.ExchangeBinance:
+		key := viper.GetString("binance-api-key")
+		secret := viper.GetString("binance-api-secret")
+		if len(key) == 0 || len(secret) == 0 {
+			return nil, errors.New("empty key or secret")
+		}
+
+		return binance.New(key, secret), nil
+
+	case types.ExchangeMax:
+		key := viper.GetString("max-api-key")
+		secret := viper.GetString("max-api-secret")
+		if len(key) == 0 || len(secret) == 0 {
+			return nil, errors.New("empty key or secret")
+		}
+
+		return max.New(key, secret), nil
+
+	}
+
+	return nil, nil
+}
diff --git a/cmd/pnl.go b/cmd/pnl.go
index ae7e120fd..e2759f4e7 100644
--- a/cmd/pnl.go
+++ b/cmd/pnl.go
@@ -2,19 +2,15 @@ package cmd
 
 import (
 	"context"
-	"fmt"
 	"strings"
 	"time"
 
-	"github.com/jmoiron/sqlx"
 	log "github.com/sirupsen/logrus"
 	"github.com/spf13/cobra"
-	"github.com/spf13/viper"
 
+	"github.com/c9s/bbgo/cmd/cmdutil"
 	"github.com/c9s/bbgo/pkg/accounting"
 	"github.com/c9s/bbgo/pkg/bbgo"
-	"github.com/c9s/bbgo/pkg/exchange/binance"
-	"github.com/c9s/bbgo/pkg/exchange/max"
 	"github.com/c9s/bbgo/pkg/service"
 	"github.com/c9s/bbgo/pkg/types"
 )
@@ -26,30 +22,6 @@ func init() {
 	RootCmd.AddCommand(pnlCmd)
 }
 
-func connectMysql() (*sqlx.DB, error) {
-	mysqlURL := viper.GetString("mysql-url")
-	mysqlURL = fmt.Sprintf("%s?parseTime=true", mysqlURL)
-	return sqlx.Connect("mysql", mysqlURL)
-}
-
-func newExchange(n types.ExchangeName) types.Exchange {
-	switch n {
-
-	case types.ExchangeBinance:
-		key := viper.GetString("binance-api-key")
-		secret := viper.GetString("binance-api-secret")
-		return binance.New(key, secret)
-
-	case types.ExchangeMax:
-		key := viper.GetString("max-api-key")
-		secret := viper.GetString("max-api-secret")
-		return max.New(key, secret)
-
-	}
-
-	return nil
-}
-
 var pnlCmd = &cobra.Command{
 	Use:          "pnl",
 	Short:        "pnl calculator",
@@ -72,9 +44,12 @@ var pnlCmd = &cobra.Command{
 			return err
 		}
 
-		exchange := newExchange(exchangeName)
+		exchange, err := cmdutil.NewExchange(exchangeName)
+		if err != nil {
+			return err
+		}
 
-		db, err := connectMysql()
+		db, err := cmdutil.ConnectMySQL()
 		if err != nil {
 			return err
 		}
diff --git a/cmd/transfers.go b/cmd/transfers.go
index 088b0daa5..8c13723d4 100644
--- a/cmd/transfers.go
+++ b/cmd/transfers.go
@@ -8,6 +8,7 @@ import (
 	log "github.com/sirupsen/logrus"
 	"github.com/spf13/cobra"
 
+	"github.com/c9s/bbgo/cmd/cmdutil"
 	"github.com/c9s/bbgo/pkg/types"
 )
 
@@ -83,7 +84,7 @@ var transferHistoryCmd = &cobra.Command{
 			}
 		}
 
-		exchange := newExchange(exchangeName)
+		exchange, _ := cmdutil.NewExchange(exchangeName)
 
 		var records timeSlice
 
diff --git a/pkg/bbgo/account.go b/pkg/bbgo/account.go
index c19ef1459..5e0464adf 100644
--- a/pkg/bbgo/account.go
+++ b/pkg/bbgo/account.go
@@ -11,11 +11,12 @@ import (
 )
 
 type Account struct {
-	mu sync.Mutex
+	sync.Mutex
 
 	Balances map[string]types.Balance
 }
 
+// TODO: rewrite this as NewAccount(map balances)
 func LoadAccount(ctx context.Context, exchange types.Exchange) (*Account, error) {
 	balances, err := exchange.QueryAccountBalances(ctx)
 	return &Account{
@@ -23,19 +24,24 @@ func LoadAccount(ctx context.Context, exchange types.Exchange) (*Account, error)
 	}, err
 }
 
-func (a *Account) BindPrivateStream(stream types.Stream) {
-	stream.OnBalanceSnapshot(func(snapshot map[string]types.Balance) {
-		a.mu.Lock()
-		defer a.mu.Unlock()
+func (a *Account) handleBalanceUpdates(balances map[string]types.Balance) {
+	a.Lock()
+	defer a.Unlock()
 
-		for _, balance := range snapshot {
-			a.Balances[balance.Currency] = balance
-		}
-	})
+	for _, balance := range balances {
+		a.Balances[balance.Currency] = balance
+	}
+}
 
+func (a *Account) BindStream(stream types.Stream) {
+	stream.OnBalanceUpdate(a.handleBalanceUpdates)
+	stream.OnBalanceSnapshot(a.handleBalanceUpdates)
 }
 
 func (a *Account) Print() {
+	a.Lock()
+	defer a.Unlock()
+
 	for _, balance := range a.Balances {
 		if util.NotZero(balance.Available) {
 			log.Infof("[trader] balance %s %f", balance.Currency, balance.Available)
diff --git a/pkg/bbgo/kline_regression.go b/pkg/bbgo/kline_regression.go
index 5dc556a6e..9b5960885 100644
--- a/pkg/bbgo/kline_regression.go
+++ b/pkg/bbgo/kline_regression.go
@@ -37,7 +37,7 @@ func (trader *BackTestTrader) SubmitOrder(cxt context.Context, order *types.Subm
 	trader.pendingOrders = append(trader.pendingOrders, order)
 }
 
-func (trader *BackTestTrader) RunStrategy(ctx context.Context, strategy MarketStrategy) (chan struct{}, error) {
+func (trader *BackTestTrader) RunStrategy(ctx context.Context, strategy SingleExchangeStrategy) (chan struct{}, error) {
 	logrus.Infof("[regression] number of kline data: %d", len(trader.SourceKLines))
 
 	done := make(chan struct{})
diff --git a/pkg/bbgo/order_processor.go b/pkg/bbgo/order_processor.go
index e44b34ac6..0cdd906ad 100644
--- a/pkg/bbgo/order_processor.go
+++ b/pkg/bbgo/order_processor.go
@@ -2,13 +2,10 @@ package bbgo
 
 import (
 	"context"
-	"fmt"
-	"math"
 
 	"github.com/pkg/errors"
 
 	"github.com/c9s/bbgo/pkg/types"
-	"github.com/c9s/bbgo/pkg/util"
 )
 
 var (
@@ -41,6 +38,7 @@ type OrderProcessor struct {
 }
 
 func (p *OrderProcessor) Submit(ctx context.Context, order *types.SubmitOrder) error {
+	/*
 	tradingCtx := p.Trader.Context
 	currentPrice := tradingCtx.CurrentPrice
 	market := order.Market
@@ -126,6 +124,8 @@ func (p *OrderProcessor) Submit(ctx context.Context, order *types.SubmitOrder) e
 
 	order.Quantity = quantity
 	order.QuantityString = market.FormatVolume(quantity)
+	 */
+
 	return p.Exchange.SubmitOrder(ctx, order)
 }
 
diff --git a/pkg/bbgo/store.go b/pkg/bbgo/store.go
index 9f79c8ca5..3aba663e8 100644
--- a/pkg/bbgo/store.go
+++ b/pkg/bbgo/store.go
@@ -28,7 +28,7 @@ func NewMarketDataStore() *MarketDataStore {
 	}
 }
 
-func (store *MarketDataStore) BindPrivateStream(stream types.Stream) {
+func (store *MarketDataStore) BindStream(stream types.Stream) {
 	stream.OnKLineClosed(store.handleKLineClosed)
 }
 
diff --git a/pkg/bbgo/strategy_test.go b/pkg/bbgo/strategy_test.go
index c94977043..113b5a85e 100644
--- a/pkg/bbgo/strategy_test.go
+++ b/pkg/bbgo/strategy_test.go
@@ -5,7 +5,7 @@ import (
 	"fmt"
 	"os"
 	"testing"
-	time "time"
+	"time"
 
 	"github.com/DATA-DOG/go-sqlmock"
 	"github.com/jmoiron/sqlx"
@@ -14,7 +14,6 @@ import (
 	"github.com/c9s/bbgo/pkg/exchange/binance"
 	"github.com/c9s/bbgo/pkg/service"
 	"github.com/c9s/bbgo/pkg/types"
-
 )
 
 func TestTradeService(t *testing.T) {
@@ -59,10 +58,11 @@ func TestEnvironment_Connect(t *testing.T) {
 
 	environment := NewEnvironment(xdb)
 	environment.AddExchange("binance", exchange).
-		Subscribe(types.KLineChannel,"BTCUSDT", types.SubscribeOptions{ })
+		Subscribe(types.KLineChannel,"BTCUSDT", types.SubscribeOptions{})
 
 	err = environment.Connect(ctx)
 	assert.NoError(t, err)
 
 	time.Sleep(5 * time.Second)
 }
+
diff --git a/pkg/bbgo/trader.go b/pkg/bbgo/trader.go
index 6a606f303..342cb943d 100644
--- a/pkg/bbgo/trader.go
+++ b/pkg/bbgo/trader.go
@@ -2,31 +2,33 @@ package bbgo
 
 import (
 	"context"
-	"fmt"
 	"strings"
 	"time"
 
-	"github.com/fsnotify/fsnotify"
 	"github.com/jmoiron/sqlx"
 	"github.com/pkg/errors"
 	log "github.com/sirupsen/logrus"
 
 	"github.com/c9s/bbgo/pkg/accounting"
-	"github.com/c9s/bbgo/pkg/bbgo/config"
 	"github.com/c9s/bbgo/pkg/service"
 	"github.com/c9s/bbgo/pkg/types"
 
 	_ "github.com/go-sql-driver/mysql"
 )
 
-// MarketStrategy represents the single Exchange strategy
-type MarketStrategy interface {
-	OnLoad(tradingContext *Context, trader types.Trader) error
-	OnNewStream(stream types.Stream) error
+// SingleExchangeStrategy represents the single Exchange strategy
+type SingleExchangeStrategy interface {
+	Run(trader types.Trader, session *ExchangeSession) error
 }
 
+type CrossExchangeStrategy interface {
+	Run(trader types.Trader, sessions map[string]*ExchangeSession) error
+}
+
+// ExchangeSession presents the exchange connection session
+// It also maintains and collects the data returned from the stream.
 type ExchangeSession struct {
-	// Session name
+	// Exchange session name
 	Name string
 
 	// The exchange account states
@@ -39,14 +41,16 @@ type ExchangeSession struct {
 
 	Exchange types.Exchange
 
-	loadedSymbols map[string]struct{}
-
 	// Markets defines market configuration of a symbol
 	Markets map[string]types.Market
 
+	LastPrices map[string]float64
+
 	// Trades collects the executed trades from the exchange
 	// map: symbol -> []trade
 	Trades map[string][]types.Trade
+
+	MarketDataStore *MarketDataStore
 }
 
 func (session *ExchangeSession) Subscribe(channel types.Channel, symbol string, options types.SubscribeOptions) *ExchangeSession {
@@ -64,7 +68,7 @@ type Environment struct {
 	TradeService *service.TradeService
 	TradeSync    *service.TradeSync
 
-	ExchangeSessions map[string]*ExchangeSession
+	sessions map[string]*ExchangeSession
 }
 
 func NewEnvironment(db *sqlx.DB) *Environment {
@@ -74,26 +78,27 @@ func NewEnvironment(db *sqlx.DB) *Environment {
 		TradeSync: &service.TradeSync{
 			Service: tradeService,
 		},
-		ExchangeSessions: make(map[string]*ExchangeSession),
+		sessions: make(map[string]*ExchangeSession),
 	}
 }
 
 func (environ *Environment) AddExchange(name string, exchange types.Exchange) (session *ExchangeSession) {
 	session = &ExchangeSession{
-		Name:     name,
-		Exchange: exchange,
-		Markets:  make(map[string]types.Market),
-		Trades:   make(map[string][]types.Trade),
+		Name:       name,
+		Exchange:   exchange,
+		Markets:    make(map[string]types.Market),
+		Trades:     make(map[string][]types.Trade),
+		LastPrices: make(map[string]float64),
 	}
 
-	environ.ExchangeSessions[name] = session
+	environ.sessions[name] = session
 	return session
 }
 
-func (environ *Environment) Connect(ctx context.Context) (err error) {
+func (environ *Environment) Init(ctx context.Context) (err error) {
 	startTime := time.Now().AddDate(0, 0, -7) // sync from 7 days ago
 
-	for _, session := range environ.ExchangeSessions {
+	for _, session := range environ.sessions {
 		loadedSymbols := make(map[string]struct{})
 		for _, sub := range session.Subscriptions {
 			loadedSymbols[sub.Symbol] = struct{}{}
@@ -119,6 +124,13 @@ func (environ *Environment) Connect(ctx context.Context) (err error) {
 
 			log.Infof("symbol %s: %d trades loaded", symbol, len(trades))
 			session.Trades[symbol] = trades
+
+			currentPrice, err := session.Exchange.QueryAveragePrice(ctx, symbol)
+			if err != nil {
+				return err
+			}
+
+			session.LastPrices[symbol] = currentPrice
 		}
 
 		session.Account, err = LoadAccount(ctx, session.Exchange)
@@ -127,6 +139,18 @@ func (environ *Environment) Connect(ctx context.Context) (err error) {
 		}
 
 		session.Stream = session.Exchange.NewStream()
+
+		session.Account.BindStream(session.Stream)
+
+		marketDataStore := NewMarketDataStore()
+		marketDataStore.BindStream(session.Stream)
+
+
+		// update last prices
+		session.Stream.OnKLineClosed(func(kline types.KLine) {
+			session.LastPrices[kline.Symbol] = kline.Close
+		})
+
 		session.Stream.OnTrade(func(trade *types.Trade) {
 			// append trades
 			session.Trades[trade.Symbol] = append(session.Trades[trade.Symbol], *trade)
@@ -135,197 +159,130 @@ func (environ *Environment) Connect(ctx context.Context) (err error) {
 				log.WithError(err).Errorf("trade insert error: %+v", *trade)
 			}
 		})
+	}
 
+	return nil
+}
+
+func (environ *Environment) Connect(ctx context.Context) error {
+	for _, session := range environ.sessions {
 		if err := session.Stream.Connect(ctx); err != nil {
 			return err
 		}
 	}
 
-	return err
+	return nil
 }
 
 type Trader struct {
-	Symbol       string
-	TradeService *service.TradeService
-	TradeSync    *service.TradeSync
-
-	// Context is trading Context
-	Context *Context
-
-	Exchange types.Exchange
-
-	reportTimer *time.Timer
-
+	reportTimer             *time.Timer
 	ProfitAndLossCalculator *accounting.ProfitAndLossCalculator
 
-	Account *Account
+	notifiers   []Notifier
+	environment *Environment
 
-	Notifiers []Notifier
-
-	ExchangeSessions map[string]*ExchangeSession
+	crossExchangeStrategies []CrossExchangeStrategy
+	exchangeStrategies      map[string][]SingleExchangeStrategy
 }
 
-func NewTrader(db *sqlx.DB, exchange types.Exchange, symbol string) *Trader {
-	tradeService := &service.TradeService{DB: db}
+func NewTrader(environ *Environment) *Trader {
 	return &Trader{
-		Symbol:       symbol,
-		Exchange:     exchange,
-		TradeService: tradeService,
-		TradeSync: &service.TradeSync{
-			Service: tradeService,
-		},
+		environment:        environ,
+		exchangeStrategies: make(map[string][]SingleExchangeStrategy),
 	}
 }
 
 func (trader *Trader) AddNotifier(notifier Notifier) {
-	trader.Notifiers = append(trader.Notifiers, notifier)
+	trader.notifiers = append(trader.notifiers, notifier)
 }
 
-func (trader *Trader) Connect(ctx context.Context) (err error) {
-	log.Info("syncing trades from exchange...")
-	startTime := time.Now().AddDate(0, 0, -7) // sync from 7 days ago
+// AttachStrategy attaches the single exchange strategy on an exchange session.
+// Single exchange strategy is the default behavior.
+func (trader *Trader) AttachStrategy(session string, strategy SingleExchangeStrategy) error {
+	if _, ok := trader.environment.sessions[session]; !ok {
+		return errors.New("session not defined")
+	}
 
-	for _, session := range trader.ExchangeSessions {
-		for symbol := range session.loadedSymbols {
-			market, ok := types.FindMarket(symbol)
-			if !ok {
-				return errors.Errorf("market %s is not defined", symbol)
-			}
+	trader.exchangeStrategies[session] = append(trader.exchangeStrategies[session], strategy)
+	return nil
+}
 
-			session.Markets[symbol] = market
+// AttachCrossExchangeStrategy attaches the cross exchange strategy
+func (trader *Trader) AttachCrossExchangeStrategy(strategy CrossExchangeStrategy) error {
+	trader.crossExchangeStrategies = append(trader.crossExchangeStrategies, strategy)
+	return nil
+}
 
+func (trader *Trader) Run(ctx context.Context) error {
+	if err := trader.environment.Init(ctx); err != nil {
+		return err
+	}
 
-			if err := trader.TradeSync.Sync(ctx, session.Exchange, symbol, startTime); err != nil {
-				return err
-			}
-
-			var trades []types.Trade
-
-			tradingFeeCurrency := session.Exchange.PlatformFeeCurrency()
-			if strings.HasPrefix(symbol, tradingFeeCurrency) {
-				trades, err = trader.TradeService.QueryForTradingFeeCurrency(symbol, tradingFeeCurrency)
-			} else {
-				trades, err = trader.TradeService.Query(symbol)
-			}
-
+	// load and run session strategies
+	for session, strategies := range trader.exchangeStrategies {
+		for _, strategy := range strategies {
+			err := strategy.Run(trader, trader.environment.sessions[session])
 			if err != nil {
 				return err
 			}
-
-			log.Infof("symbol %s: %d trades loaded", symbol, len(trades))
-			session.Trades[symbol] = trades
-
-			stockManager := &StockDistribution{
-				Symbol:             symbol,
-				TradingFeeCurrency: tradingFeeCurrency,
-			}
-
-			checkpoints, err := stockManager.AddTrades(trades)
-			if err != nil {
-				return err
-			}
-
-			log.Infof("symbol %s: found stock checkpoints: %+v", symbol, checkpoints)
 		}
+	}
 
-		session.Account, err = LoadAccount(ctx, session.Exchange)
-		if err != nil {
-			return err
-		}
-
-		session.Stream = session.Exchange.NewStream()
-		if err != nil {
-			return err
-		}
-
-		if err := session.Stream.Connect(ctx); err != nil {
+	for _, strategy := range trader.crossExchangeStrategies {
+		if err := strategy.Run(trader, trader.environment.sessions) ; err != nil {
 			return err
 		}
 	}
 
-	return nil
+
+	return trader.environment.Connect(ctx)
+	/*
+		stockManager := &StockDistribution{
+			Symbol:             symbol,
+			TradingFeeCurrency: tradingFeeCurrency,
+		}
+
+		checkpoints, err := stockManager.AddTrades(trades)
+		if err != nil {
+			return err
+		}
+
+		log.Infof("symbol %s: found stock checkpoints: %+v", symbol, checkpoints)
+	*/
 }
 
 func (trader *Trader) Initialize(ctx context.Context, startTime time.Time) error {
-	// query all trades from database so that we can get the correct pnl
-	var err error
-	var trades []types.Trade
-	tradingFeeCurrency := trader.Exchange.PlatformFeeCurrency()
-	if strings.HasPrefix(trader.Symbol, tradingFeeCurrency) {
-		trades, err = trader.TradeService.QueryForTradingFeeCurrency(trader.Symbol, tradingFeeCurrency)
-	} else {
-		trades, err = trader.TradeService.Query(trader.Symbol)
-	}
-
-	if err != nil {
-		return err
-	}
-
-	log.Infof("%d trades loaded", len(trades))
-
-	stockManager := &StockDistribution{
-		Symbol:             trader.Symbol,
-		TradingFeeCurrency: tradingFeeCurrency,
-	}
-
-	checkpoints, err := stockManager.AddTrades(trades)
-	if err != nil {
-		return err
-	}
-
-	log.Infof("found checkpoints: %+v", checkpoints)
-
-	market, ok := types.FindMarket(trader.Symbol)
-	if !ok {
-		return fmt.Errorf("%s market not found", trader.Symbol)
-	}
-
-	currentPrice, err := trader.Exchange.QueryAveragePrice(ctx, trader.Symbol)
-	if err != nil {
-		return err
-	}
-
-	trader.Context = &Context{
-		CurrentPrice: currentPrice,
-		Symbol:       trader.Symbol,
-		Market:       market,
-		StockManager: stockManager,
-	}
-
 	/*
-		if len(checkpoints) > 0 {
-			// get the last checkpoint
-			idx := checkpoints[len(checkpoints)-1]
-			if idx < len(trades)-1 {
-				trades = trades[idx:]
-				firstTrade := trades[0]
-				pnlStartTime = firstTrade.Time
-				notifier.Notify("%s Found the latest trade checkpoint %s", firstTrade.Symbol, firstTrade.Time, firstTrade)
-			}
+		currentPrice, err := trader.Exchange.QueryAveragePrice(ctx, trader.Symbol)
+		if err != nil {
+			return err
+		}
+
+		trader.Context = &Context{
+			CurrentPrice: currentPrice,
+			Symbol:       trader.Symbol,
+			Market:       market,
+			StockManager: stockManager,
 		}
 	*/
 
-	trader.ProfitAndLossCalculator = &accounting.ProfitAndLossCalculator{
-		TradingFeeCurrency: tradingFeeCurrency,
-		Symbol:             trader.Symbol,
-		StartTime:          startTime,
-		CurrentPrice:       currentPrice,
-		Trades:             trades,
-	}
-
-	account, err := LoadAccount(ctx, trader.Exchange)
-	if err != nil {
-		return err
-	}
-
-	trader.Account = account
-	trader.Context.Balances = account.Balances
-	account.Print()
+	/*
+		trader.ProfitAndLossCalculator = &accounting.ProfitAndLossCalculator{
+			TradingFeeCurrency: tradingFeeCurrency,
+			Symbol:             trader.Symbol,
+			StartTime:          startTime,
+			CurrentPrice:       currentPrice,
+			Trades:             trades,
+		}
+	*/
 
+	// trader.Context.Balances = account.Balances
+	// account.Print()
 	return nil
 }
 
-func (trader *Trader) RunStrategyWithHotReload(ctx context.Context, strategy MarketStrategy, configFile string) (chan struct{}, error) {
+/*
+func (trader *Trader) RunStrategyWithHotReload(ctx context.Context, strategy SingleExchangeStrategy, configFile string) (chan struct{}, error) {
 	var done = make(chan struct{})
 	var configWatcherDone = make(chan struct{})
 
@@ -400,8 +357,10 @@ func (trader *Trader) RunStrategyWithHotReload(ctx context.Context, strategy Mar
 
 	return done, nil
 }
+*/
 
-func (trader *Trader) RunStrategy(ctx context.Context, strategy MarketStrategy) (chan struct{}, error) {
+/*
+func (trader *Trader) RunStrategy(ctx context.Context, strategy SingleExchangeStrategy) (chan struct{}, error) {
 	if err := strategy.OnLoad(trader.Context, trader); err != nil {
 		return nil, err
 	}
@@ -410,9 +369,9 @@ func (trader *Trader) RunStrategy(ctx context.Context, strategy MarketStrategy)
 
 	// bind kline store to the stream
 	klineStore := NewMarketDataStore()
-	klineStore.BindPrivateStream(stream)
+	klineStore.BindStream(stream)
 
-	trader.Account.BindPrivateStream(stream)
+	trader.Account.BindStream(stream)
 
 	if err := strategy.OnNewStream(stream); err != nil {
 		return nil, err
@@ -423,14 +382,6 @@ func (trader *Trader) RunStrategy(ctx context.Context, strategy MarketStrategy)
 	})
 
 	stream.OnTrade(func(trade *types.Trade) {
-		if trade.Symbol != trader.Symbol {
-			return
-		}
-
-		if err := trader.TradeService.Insert(*trade); err != nil {
-			log.WithError(err).Error("trade insert error")
-		}
-
 		trader.NotifyTrade(trade)
 		trader.ProfitAndLossCalculator.AddTrade(*trade)
 		_, err := trader.Context.StockManager.AddTrades([]types.Trade{*trade})
@@ -472,6 +423,7 @@ func (trader *Trader) RunStrategy(ctx context.Context, strategy MarketStrategy)
 
 	return done, nil
 }
+*/
 
 func (trader *Trader) reportPnL() {
 	report := trader.ProfitAndLossCalculator.Calculate()
@@ -480,19 +432,19 @@ func (trader *Trader) reportPnL() {
 }
 
 func (trader *Trader) NotifyPnL(report *accounting.ProfitAndLossReport) {
-	for _, n := range trader.Notifiers {
+	for _, n := range trader.notifiers {
 		n.NotifyPnL(report)
 	}
 }
 
 func (trader *Trader) NotifyTrade(trade *types.Trade) {
-	for _, n := range trader.Notifiers {
+	for _, n := range trader.notifiers {
 		n.NotifyTrade(trade)
 	}
 }
 
 func (trader *Trader) Notify(msg string, args ...interface{}) {
-	for _, n := range trader.Notifiers {
+	for _, n := range trader.notifiers {
 		n.Notify(msg, args...)
 	}
 }
@@ -506,8 +458,9 @@ func (trader *Trader) SubmitOrder(ctx context.Context, order *types.SubmitOrder)
 		MinAssetBalance: 0,
 		MinProfitSpread: 0,
 		MaxOrderAmount:  0,
-		Exchange:        trader.Exchange,
-		Trader:          trader,
+		// FIXME:
+		// Exchange:        trader.Exchange,
+		Trader: trader,
 	}
 
 	err := orderProcessor.Submit(ctx, order)
diff --git a/pkg/strategy/buyandhold/main.go b/pkg/strategy/buyandhold/main.go
new file mode 100644
index 000000000..582646568
--- /dev/null
+++ b/pkg/strategy/buyandhold/main.go
@@ -0,0 +1,30 @@
+package buyandhold
+
+import (
+	"github.com/c9s/bbgo/pkg/bbgo"
+	"github.com/c9s/bbgo/pkg/types"
+)
+
+type Strategy struct {
+	symbol string
+}
+
+func New(symbol string) *Strategy {
+	return &Strategy{
+		symbol: symbol,
+	}
+}
+
+func (s *Strategy) Run(trader types.Trader, session *bbgo.ExchangeSession) error {
+	session.Subscribe(types.KLineChannel, s.symbol, types.SubscribeOptions{})
+	session.Stream.OnKLineClosed(func(kline types.KLine) {
+		// trader.SubmitOrder(ctx, ....)
+	})
+
+	return nil
+}
+
+
+
+
+