@@ -96,7 +96,7 @@ dir, err := ioutil.TempDir("", "tmpdb")
 	if err != nil {
 		panic(err)
 	}
-	sdb, err := statedb.NewStateDB(dir, false, 0)
+	sdb, err := statedb.NewStateDB(dir, statedb.TypeTxSelector, 0)
 	if err != nil {
 		panic(err)
 	}

@@ -28,7 +28,7 @@
 // NewBatchBuilder constructs a new BatchBuilder, and executes the bb.Reset
 // method
 func NewBatchBuilder(dbpath string, synchronizerStateDB *statedb.StateDB, configCircuits []ConfigCircuit, batchNum common.BatchNum, nLevels uint64) (*BatchBuilder, error) {
-	localStateDB, err := statedb.NewLocalStateDB(dbpath, synchronizerStateDB, true, int(nLevels))
+	localStateDB, err := statedb.NewLocalStateDB(dbpath, synchronizerStateDB, statedb.TypeBatchBuilder, int(nLevels))
 	if err != nil {
 		return nil, err
 	}
@@ -52,7 +52,7 @@ }
 
 // BuildBatch takes the transactions and returns the common.ZKInputs of the next batch
 func (bb *BatchBuilder) BuildBatch(configBatch *ConfigBatch, l1usertxs, l1coordinatortxs []*common.L1Tx, pooll2txs []*common.PoolL2Tx, tokenIDs []common.TokenID) (*common.ZKInputs, error) {
-	zkInputs, _, err := bb.localStateDB.ProcessTxs(false, true, l1usertxs, l1coordinatortxs, pooll2txs)
+	zkInputs, _, err := bb.localStateDB.ProcessTxs(l1usertxs, l1coordinatortxs, pooll2txs)
 	if err != nil {
 		return nil, err
 	}

@@ -13,7 +13,7 @@ func TestBatchBuilder(t *testing.T) {
 	dir, err := ioutil.TempDir("", "tmpdb")
 	require.Nil(t, err)
 
-	synchDB, err := statedb.NewStateDB(dir, false, 0)
+	synchDB, err := statedb.NewStateDB(dir, statedb.TypeBatchBuilder, 0)
 	assert.Nil(t, err)
 
 	bbDir, err := ioutil.TempDir("", "tmpBatchBuilderDB")

@@ -21,11 +21,20 @@
 func newTestModules(t *testing.T) (*txselector.TxSelector, *batchbuilder.BatchBuilder) { // FUTURE once Synchronizer is ready, should return it also
 	nLevels := 32
 
-	synchDB, err := ioutil.TempDir("", "tmpSynchDB")
+	synchDBPath, err := ioutil.TempDir("", "tmpSynchDB")
 	require.Nil(t, err)
-	sdb, err := statedb.NewStateDB(synchDB, true, nLevels)
+	synchSdb, err := statedb.NewStateDB(synchDBPath, statedb.TypeSynchronizer, nLevels)
 	assert.Nil(t, err)
 
+	// txselDBPath, err := ioutil.TempDir("", "tmpTxSelDB")
+	// require.Nil(t, err)
+	// bbDBPath, err := ioutil.TempDir("", "tmpBBDB")
+	// require.Nil(t, err)
+	// txselSdb, err := statedb.NewLocalStateDB(txselDBPath, synchSdb, statedb.TypeTxSelector, nLevels)
+	// assert.Nil(t, err)
+	// bbSdb, err := statedb.NewLocalStateDB(bbDBPath, synchSdb, statedb.TypeBatchBuilder, nLevels)
+	// assert.Nil(t, err)
+
 	pass := os.Getenv("POSTGRES_PASS")
 	db, err := dbUtils.InitSQLDB(5432, "localhost", "hermez", pass, "hermez")
 	require.Nil(t, err)
@@ -33,12 +42,12 @@ l2DB := l2db.NewL2DB(db, 10, 100, 24*time.Hour)
 
 	txselDir, err := ioutil.TempDir("", "tmpTxSelDB")
 	require.Nil(t, err)
-	txsel, err := txselector.NewTxSelector(txselDir, sdb, l2DB, 10, 10, 10)
+	txsel, err := txselector.NewTxSelector(txselDir, synchSdb, l2DB, 10, 10, 10)
 	assert.Nil(t, err)
 
 	bbDir, err := ioutil.TempDir("", "tmpBatchBuilderDB")
 	require.Nil(t, err)
-	bb, err := batchbuilder.NewBatchBuilder(bbDir, sdb, nil, 0, uint64(nLevels))
+	bb, err := batchbuilder.NewBatchBuilder(bbDir, synchSdb, nil, 0, uint64(nLevels))
 	assert.Nil(t, err)
 
 	// l1Txs, coordinatorL1Txs, poolL2Txs := test.GenerateTestTxsFromSet(t, test.SetTest0)

@@ -15,31 +15,45 @@ )
 
 // TODO(Edu): Document here how StateDB is kept consistent
 
-// ErrStateDBWithoutMT is used when a method that requires a MerkleTree is
-// called in a StateDB that does not have a MerkleTree defined
-var ErrStateDBWithoutMT = errors.New("Can not call method to use MerkleTree in a StateDB without MerkleTree")
+var (
+	// ErrStateDBWithoutMT is used when a method that requires a MerkleTree
+	// is called in a StateDB that does not have a MerkleTree defined
+	ErrStateDBWithoutMT = errors.New("Can not call method to use MerkleTree in a StateDB without MerkleTree")
 
-// ErrAccountAlreadyExists is used when CreateAccount is called and the Account
-// already exists
-var ErrAccountAlreadyExists = errors.New("Can not CreateAccount because Account already exists")
+	// ErrAccountAlreadyExists is used when CreateAccount is called and the
+	// Account already exists
+	ErrAccountAlreadyExists = errors.New("Can not CreateAccount because Account already exists")
 
-// ErrToIdxNotFound is used when trying to get the ToIdx from ToEthAddr or
-// ToEthAddr&ToBJJ
-var ErrToIdxNotFound = errors.New("ToIdx can not be found")
+	// ErrToIdxNotFound is used when trying to get the ToIdx from ToEthAddr
+	// or ToEthAddr&ToBJJ
+	ErrToIdxNotFound = errors.New("ToIdx can not be found")
 
-// KeyCurrentBatch is used as key in the db to store the current BatchNum
-var KeyCurrentBatch = []byte("currentbatch")
+	// KeyCurrentBatch is used as key in the db to store the current BatchNum
+	KeyCurrentBatch = []byte("currentbatch")
+)
 
-// PathStateDB defines the subpath of the StateDB
-const PathStateDB = "/statedb"
+const (
+	// PathStateDB defines the subpath of the StateDB
+	PathStateDB = "/statedb"
+	// PathBatchNum defines the subpath of the Batch Checkpoint in the
+	// subpath of the StateDB
+	PathBatchNum = "/BatchNum"
+	// PathCurrent defines the subpath of the current Batch in the subpath
+	// of the StateDB
+	PathCurrent = "/current"
+	// TypeSynchronizer defines a StateDB used by the Synchronizer, that
+	// generates the ExitTree when processing the txs
+	TypeSynchronizer = "synchronizer"
+	// TypeTxSelector defines a StateDB used by the TxSelector, without
+	// computing ExitTree neither the ZKInputs
+	TypeTxSelector = "txselector"
+	// TypeBatchBuilder defines a StateDB used by the BatchBuilder, that
+	// generates the ExitTree and the ZKInput when processing the txs
+	TypeBatchBuilder = "batchbuilder"
+)
 
-// PathBatchNum defines the subpath of the Batch Checkpoint in the subpath of
-// the StateDB
-const PathBatchNum = "/BatchNum"
-
-// PathCurrent defines the subpath of the current Batch in the subpath of the
-// StateDB
-const PathCurrent = "/current"
+// TypeStateDB determines the type of StateDB
+type TypeStateDB string
 
 // StateDB represents the StateDB object
 type StateDB struct {
@@ -47,6 +61,7 @@ path         string
 	currentBatch common.BatchNum
 	db           *pebble.PebbleStorage
 	mt           *merkletree.MerkleTree
+	typ          TypeStateDB
 	// idx holds the current Idx that the BatchBuilder is using
 	idx common.Idx
 	zki *common.ZKInputs
@@ -55,7 +70,7 @@ }
 
 // NewStateDB creates a new StateDB, allowing to use an in-memory or in-disk
 // storage
-func NewStateDB(path string, withMT bool, nLevels int) (*StateDB, error) {
+func NewStateDB(path string, typ TypeStateDB, nLevels int) (*StateDB, error) {
 	var sto *pebble.PebbleStorage
 	var err error
 	sto, err = pebble.NewPebbleStorage(path+PathStateDB+PathCurrent, false)
@@ -64,17 +79,21 @@ return nil, err
 	}
 
 	var mt *merkletree.MerkleTree = nil
-	if withMT {
+	if typ == TypeSynchronizer || typ == TypeBatchBuilder {
 		mt, err = merkletree.NewMerkleTree(sto, nLevels)
 		if err != nil {
 			return nil, err
 		}
 	}
+	if typ == TypeTxSelector && nLevels != 0 {
+		return nil, fmt.Errorf("invalid StateDB parameters: StateDB type==TypeStateDB can not have nLevels!=0")
+	}
 
 	sdb := &StateDB{
 		path: path + PathStateDB,
 		db:   sto,
 		mt:   mt,
+		typ:  typ,
 	}
 
 	// load currentBatch
@@ -382,8 +401,8 @@ }
 
 // NewLocalStateDB returns a new LocalStateDB connected to the given
 // synchronizerDB
-func NewLocalStateDB(path string, synchronizerDB *StateDB, withMT bool, nLevels int) (*LocalStateDB, error) {
-	s, err := NewStateDB(path, withMT, nLevels)
+func NewLocalStateDB(path string, synchronizerDB *StateDB, typ TypeStateDB, nLevels int) (*LocalStateDB, error) {
+	s, err := NewStateDB(path, typ, nLevels)
 	if err != nil {
 		return nil, err
 	}

@@ -38,7 +38,7 @@ func TestNewStateDBIntermediateState(t *testing.T) {
 	dir, err := ioutil.TempDir("", "tmpdb")
 	require.Nil(t, err)
 
-	sdb, err := NewStateDB(dir, false, 0)
+	sdb, err := NewStateDB(dir, TypeTxSelector, 0)
 	assert.Nil(t, err)
 
 	// test values
@@ -60,7 +60,7 @@ assert.Equal(t, v0, v)
 
 	// call NewStateDB which should get the db at the last checkpoint state
 	// executing a Reset (discarding the last 'testkey0'&'testvalue0' data)
-	sdb, err = NewStateDB(dir, false, 0)
+	sdb, err = NewStateDB(dir, TypeTxSelector, 0)
 	assert.Nil(t, err)
 	v, err = sdb.db.Get(k0)
 	assert.NotNil(t, err)
@@ -102,7 +102,7 @@ assert.Equal(t, v1, v)
 
 	// call NewStateDB which should get the db at the last checkpoint state
 	// executing a Reset (discarding the last 'testkey1'&'testvalue1' data)
-	sdb, err = NewStateDB(dir, false, 0)
+	sdb, err = NewStateDB(dir, TypeTxSelector, 0)
 	assert.Nil(t, err)
 
 	v, err = sdb.db.Get(k0)
@@ -119,7 +119,7 @@ func TestStateDBWithoutMT(t *testing.T) {
 	dir, err := ioutil.TempDir("", "tmpdb")
 	require.Nil(t, err)
 
-	sdb, err := NewStateDB(dir, false, 0)
+	sdb, err := NewStateDB(dir, TypeTxSelector, 0)
 	assert.Nil(t, err)
 
 	// create test accounts
@@ -168,7 +168,7 @@ func TestStateDBWithMT(t *testing.T) {
 	dir, err := ioutil.TempDir("", "tmpdb")
 	require.Nil(t, err)
 
-	sdb, err := NewStateDB(dir, true, 32)
+	sdb, err := NewStateDB(dir, TypeSynchronizer, 32)
 	assert.Nil(t, err)
 
 	// create test accounts
@@ -219,7 +219,7 @@ func TestCheckpoints(t *testing.T) {
 	dir, err := ioutil.TempDir("", "sdb")
 	require.Nil(t, err)
 
-	sdb, err := NewStateDB(dir, true, 32)
+	sdb, err := NewStateDB(dir, TypeSynchronizer, 32)
 	assert.Nil(t, err)
 
 	// create test accounts
@@ -285,7 +285,7 @@
 	// Create a LocalStateDB from the initial StateDB
 	dirLocal, err := ioutil.TempDir("", "ldb")
 	require.Nil(t, err)
-	ldb, err := NewLocalStateDB(dirLocal, sdb, true, 32)
+	ldb, err := NewLocalStateDB(dirLocal, sdb, TypeBatchBuilder, 32)
 	assert.Nil(t, err)
 
 	// get checkpoint 4 from sdb (StateDB) to ldb (LocalStateDB)
@@ -305,7 +305,7 @@
 	// Create a 2nd LocalStateDB from the initial StateDB
 	dirLocal2, err := ioutil.TempDir("", "ldb2")
 	require.Nil(t, err)
-	ldb2, err := NewLocalStateDB(dirLocal2, sdb, true, 32)
+	ldb2, err := NewLocalStateDB(dirLocal2, sdb, TypeBatchBuilder, 32)
 	assert.Nil(t, err)
 
 	// get checkpoint 4 from sdb (StateDB) to ldb (LocalStateDB)

@@ -30,11 +30,13 @@ acc     common.Account
 }
 
 // ProcessTxs process the given L1Txs & L2Txs applying the needed updates to
-// the StateDB depending on the transaction Type. Returns the common.ZKInputs
-// to generate the SnarkProof later used by the BatchBuilder, and if
-// cmpExitTree is set to true, returns common.ExitTreeLeaf that is later used
-// by the Synchronizer to update the HistoryDB.
-func (s *StateDB) ProcessTxs(cmpExitTree, cmpZKInputs bool, l1usertxs, l1coordinatortxs []*common.L1Tx, l2txs []*common.PoolL2Tx) (*common.ZKInputs, []*common.ExitInfo, error) {
+// the StateDB depending on the transaction Type.  If StateDB
+// type==TypeBatchBuilder, returns the common.ZKInputs to generate the
+// SnarkProof later used by the BatchBuilder.  If StateDB
+// type==TypeSynchronizer, assumes that the call is done from the Synchronizer,
+// returns common.ExitTreeLeaf that is later used by the Synchronizer to update
+// the HistoryDB, and adds Nonce & TokenID to the L2Txs.
+func (s *StateDB) ProcessTxs(l1usertxs, l1coordinatortxs []*common.L1Tx, l2txs []*common.PoolL2Tx) (*common.ZKInputs, []common.ExitInfo, error) {
 	var err error
 	var exitTree *merkletree.MerkleTree
 
@@ -50,7 +52,7 @@ return nil, nil, nil
 	}
 	exits := make([]processedExit, nTx)
 
-	if cmpZKInputs {
+	if s.typ == TypeBatchBuilder {
 		s.zki = common.NewZKInputs(nTx, 24, 32) // TODO this values will be parameters of the function, taken from config file/coordinator call
 		s.zki.OldLastIdx = (s.idx - 1).BigInt()
 		s.zki.OldStateRoot = s.mt.Root().BigInt()
@@ -58,7 +60,7 @@ }
 
 	// TBD if ExitTree is only in memory or stored in disk, for the moment
 	// only needed in memory
-	if cmpExitTree {
+	if s.typ == TypeSynchronizer || s.typ == TypeBatchBuilder {
 		exitTree, err = merkletree.NewMerkleTree(memory.NewMemoryStorage(), s.mt.MaxLevels())
 		if err != nil {
 			return nil, nil, err
@@ -71,15 +73,15 @@ exitIdx, exitAccount, newExit, err := s.processL1Tx(exitTree, tx)
 		if err != nil {
 			return nil, nil, err
 		}
-		if exitIdx != nil && cmpExitTree {
-			exits[s.i] = processedExit{
-				exit:    true,
-				newExit: newExit,
-				idx:     *exitIdx,
-				acc:     *exitAccount,
+		if s.typ == TypeSynchronizer || s.typ == TypeBatchBuilder {
+			if exitIdx != nil && exitTree != nil {
+				exits[s.i] = processedExit{
+					exit:    true,
+					newExit: newExit,
+					idx:     *exitIdx,
+					acc:     *exitAccount,
+				}
 			}
-		}
-		if s.zki != nil {
 			s.i++
 		}
 	}
@@ -91,15 +93,15 @@ }
 		if exitIdx != nil {
 			log.Error("Unexpected Exit in L1CoordinatorTx")
 		}
-		if exitIdx != nil && cmpExitTree {
-			exits[s.i] = processedExit{
-				exit:    true,
-				newExit: newExit,
-				idx:     *exitIdx,
-				acc:     *exitAccount,
+		if s.typ == TypeSynchronizer || s.typ == TypeBatchBuilder {
+			if exitIdx != nil && exitTree != nil {
+				exits[s.i] = processedExit{
+					exit:    true,
+					newExit: newExit,
+					idx:     *exitIdx,
+					acc:     *exitAccount,
+				}
 			}
-		}
-		if s.zki != nil {
 			s.i++
 		}
 	}
@@ -108,26 +110,26 @@ exitIdx, exitAccount, newExit, err := s.processL2Tx(exitTree, tx)
 		if err != nil {
 			return nil, nil, err
 		}
-		if exitIdx != nil && cmpExitTree {
-			exits[s.i] = processedExit{
-				exit:    true,
-				newExit: newExit,
-				idx:     *exitIdx,
-				acc:     *exitAccount,
+		if s.typ == TypeSynchronizer || s.typ == TypeBatchBuilder {
+			if exitIdx != nil && exitTree != nil {
+				exits[s.i] = processedExit{
+					exit:    true,
+					newExit: newExit,
+					idx:     *exitIdx,
+					acc:     *exitAccount,
+				}
 			}
-		}
-		if s.zki != nil {
 			s.i++
 		}
 	}
 
-	if !cmpExitTree && !cmpZKInputs {
+	if s.typ == TypeTxSelector {
 		return nil, nil, nil
 	}
 
 	// once all txs processed (exitTree root frozen), for each Exit,
 	// generate common.ExitInfo data
-	var exitInfos []*common.ExitInfo
+	var exitInfos []common.ExitInfo
 	for i := 0; i < nTx; i++ {
 		if !exits[i].exit {
 			continue
@@ -141,7 +143,7 @@ if err != nil {
 			return nil, nil, err
 		}
 		// 1. generate common.ExitInfo
-		ei := &common.ExitInfo{
+		ei := common.ExitInfo{
 			AccountIdx:  exitIdx,
 			MerkleProof: p,
 			Balance:     exitAccount.Balance,
@@ -168,7 +170,7 @@ s.zki.OldKey2[i] = p.OldKey.BigInt()
 			s.zki.OldValue2[i] = p.OldValue.BigInt()
 		}
 	}
-	if !cmpZKInputs {
+	if s.typ == TypeSynchronizer {
 		return nil, exitInfos, nil
 	}
 
@@ -343,6 +345,17 @@ // s.zki.RqToBJJAy[s.i] = tx.ToBJJ.Y // TODO
 		s.zki.S[s.i] = tx.Signature.S
 		s.zki.R8x[s.i] = tx.Signature.R8.X
 		s.zki.R8y[s.i] = tx.Signature.R8.Y
+	}
+
+	// if StateDB type==TypeSynchronizer, will need to add Nonce and
+	// TokenID to the transaction
+	if s.typ == TypeSynchronizer {
+		acc, err := s.GetAccount(tx.ToIdx)
+		if err != nil {
+			return nil, nil, false, err
+		}
+		tx.Nonce = acc.Nonce
+		tx.TokenID = acc.TokenID
 	}
 
 	switch tx.Type {

@@ -19,7 +19,7 @@ func TestProcessTxs(t *testing.T) {
 	dir, err := ioutil.TempDir("", "tmpdb")
 	require.Nil(t, err)
 
-	sdb, err := NewStateDB(dir, true, 32)
+	sdb, err := NewStateDB(dir, TypeBatchBuilder, 32)
 	assert.Nil(t, err)
 
 	// generate test transactions from test.SetTest0 code
@@ -36,7 +36,7 @@ // iterate for each batch
 	for i := 0; i < len(l1Txs); i++ {
 		// l2Txs := common.PoolL2TxsToL2Txs(poolL2Txs[i])
 
-		_, _, err := sdb.ProcessTxs(true, true, l1Txs[i], coordinatorL1Txs[i], poolL2Txs[i])
+		_, _, err := sdb.ProcessTxs(l1Txs[i], coordinatorL1Txs[i], poolL2Txs[i])
 		require.Nil(t, err)
 	}
 
@@ -45,11 +45,68 @@ assert.Nil(t, err)
 	assert.Equal(t, "23", acc.Balance.String())
 }
 
-func TestProcessTxsBatchByBatch(t *testing.T) {
+func TestProcessTxsSynchronizer(t *testing.T) {
+	// TODO once TTGL is updated, use the blockchain L2Tx (not PoolL2Tx) for
+	// the Synchronizer tests
+
+	dir, err := ioutil.TempDir("", "tmpdb")
+	require.Nil(t, err)
+
+	sdb, err := NewStateDB(dir, TypeSynchronizer, 32)
+	assert.Nil(t, err)
+
+	// generate test transactions from test.SetTest0 code
+	parser := test.NewParser(strings.NewReader(test.SetTest0))
+	instructions, err := parser.Parse()
+	assert.Nil(t, err)
+
+	l1Txs, coordinatorL1Txs, poolL2Txs, _ := test.GenerateTestTxs(t, instructions)
+	assert.Equal(t, 29, len(l1Txs[0]))
+	assert.Equal(t, 0, len(coordinatorL1Txs[0]))
+	assert.Equal(t, 21, len(poolL2Txs[0]))
+	assert.Equal(t, 5, len(l1Txs[1]))
+	assert.Equal(t, 1, len(coordinatorL1Txs[1]))
+	assert.Equal(t, 55, len(poolL2Txs[1]))
+	assert.Equal(t, 10, len(l1Txs[2]))
+	assert.Equal(t, 0, len(coordinatorL1Txs[2]))
+	assert.Equal(t, 7, len(poolL2Txs[2]))
+
+	// use first batch
+	// l2txs := common.PoolL2TxsToL2Txs(poolL2Txs[0])
+	_, exitInfos, err := sdb.ProcessTxs(l1Txs[0], coordinatorL1Txs[0], poolL2Txs[0])
+	require.Nil(t, err)
+	// TODO once TTGL is updated, add a check that a input poolL2Tx with
+	// Nonce & TokenID =0, after ProcessTxs call has the expected value
+
+	assert.Equal(t, 0, len(exitInfos))
+	acc, err := sdb.GetAccount(common.Idx(256))
+	assert.Nil(t, err)
+	assert.Equal(t, "28", acc.Balance.String())
+
+	// use second batch
+	// l2txs = common.PoolL2TxsToL2Txs(poolL2Txs[1])
+	_, exitInfos, err = sdb.ProcessTxs(l1Txs[1], coordinatorL1Txs[1], poolL2Txs[1])
+	require.Nil(t, err)
+	assert.Equal(t, 5, len(exitInfos))
+	acc, err = sdb.GetAccount(common.Idx(256))
+	require.Nil(t, err)
+	assert.Equal(t, "48", acc.Balance.String())
+
+	// use third batch
+	// l2txs = common.PoolL2TxsToL2Txs(poolL2Txs[2])
+	_, exitInfos, err = sdb.ProcessTxs(l1Txs[2], coordinatorL1Txs[2], poolL2Txs[2])
+	require.Nil(t, err)
+	assert.Equal(t, 1, len(exitInfos))
+	acc, err = sdb.GetAccount(common.Idx(256))
+	assert.Nil(t, err)
+	assert.Equal(t, "23", acc.Balance.String())
+}
+
+func TestProcessTxsBatchBuilder(t *testing.T) {
 	dir, err := ioutil.TempDir("", "tmpdb")
 	require.Nil(t, err)
 
-	sdb, err := NewStateDB(dir, true, 32)
+	sdb, err := NewStateDB(dir, TypeBatchBuilder, 32)
 	assert.Nil(t, err)
 
 	// generate test transactions from test.SetTest0 code
@@ -70,7 +127,7 @@ assert.Equal(t, 7, len(poolL2Txs[2]))
 
 	// use first batch
 	// l2txs := common.PoolL2TxsToL2Txs(poolL2Txs[0])
-	_, exitInfos, err := sdb.ProcessTxs(true, true, l1Txs[0], coordinatorL1Txs[0], poolL2Txs[0])
+	_, exitInfos, err := sdb.ProcessTxs(l1Txs[0], coordinatorL1Txs[0], poolL2Txs[0])
 	require.Nil(t, err)
 	assert.Equal(t, 0, len(exitInfos))
 	acc, err := sdb.GetAccount(common.Idx(256))
@@ -79,7 +136,7 @@ assert.Equal(t, "28", acc.Balance.String())
 
 	// use second batch
 	// l2txs = common.PoolL2TxsToL2Txs(poolL2Txs[1])
-	_, exitInfos, err = sdb.ProcessTxs(true, true, l1Txs[1], coordinatorL1Txs[1], poolL2Txs[1])
+	_, exitInfos, err = sdb.ProcessTxs(l1Txs[1], coordinatorL1Txs[1], poolL2Txs[1])
 	require.Nil(t, err)
 	assert.Equal(t, 5, len(exitInfos))
 	acc, err = sdb.GetAccount(common.Idx(256))
@@ -88,7 +145,7 @@ assert.Equal(t, "48", acc.Balance.String())
 
 	// use third batch
 	// l2txs = common.PoolL2TxsToL2Txs(poolL2Txs[2])
-	_, exitInfos, err = sdb.ProcessTxs(true, true, l1Txs[2], coordinatorL1Txs[2], poolL2Txs[2])
+	_, exitInfos, err = sdb.ProcessTxs(l1Txs[2], coordinatorL1Txs[2], poolL2Txs[2])
 	require.Nil(t, err)
 	assert.Equal(t, 1, len(exitInfos))
 	acc, err = sdb.GetAccount(common.Idx(256))
@@ -100,7 +157,7 @@ func TestZKInputsGeneration(t *testing.T) {
 	dir, err := ioutil.TempDir("", "tmpdb")
 	require.Nil(t, err)
 
-	sdb, err := NewStateDB(dir, true, 32)
+	sdb, err := NewStateDB(dir, TypeBatchBuilder, 32)
 	assert.Nil(t, err)
 
 	// generate test transactions from test.SetTest0 code
@@ -113,7 +170,7 @@ assert.Equal(t, 29, len(l1Txs[0]))
 	assert.Equal(t, 0, len(coordinatorL1Txs[0]))
 	assert.Equal(t, 21, len(poolL2Txs[0]))
 
-	zki, _, err := sdb.ProcessTxs(false, true, l1Txs[0], coordinatorL1Txs[0], poolL2Txs[0])
+	zki, _, err := sdb.ProcessTxs(l1Txs[0], coordinatorL1Txs[0], poolL2Txs[0])
 	require.Nil(t, err)
 
 	s, err := json.Marshal(zki)

@@ -16,7 +16,7 @@ func TestGetIdx(t *testing.T) {
 	dir, err := ioutil.TempDir("", "tmpdb")
 	require.Nil(t, err)
 
-	sdb, err := NewStateDB(dir, false, 0)
+	sdb, err := NewStateDB(dir, TypeTxSelector, 0)
 	assert.Nil(t, err)
 
 	var sk babyjub.PrivateKey

@@ -72,7 +72,7 @@ }
 
 	historyDB := historydb.NewHistoryDB(db)
 
-	stateDB, err := statedb.NewStateDB(cfg.StateDB.Path, true, 32)
+	stateDB, err := statedb.NewStateDB(cfg.StateDB.Path, statedb.TypeSynchronizer, 32)
 	if err != nil {
 		return nil, err
 	}

@@ -58,7 +58,7 @@ l1UserTxs        []*common.L1Tx
 	l1CoordinatorTxs []*common.L1Tx
 	l2Txs            []*common.L2Tx
 	createdAccounts  []*common.Account
-	exitTree         []*common.ExitInfo
+	exitTree         []common.ExitInfo
 	batch            *common.Batch
 }
 
@@ -69,7 +69,7 @@ l1UserTxs:        make([]*common.L1Tx, 0),
 		l1CoordinatorTxs: make([]*common.L1Tx, 0),
 		l2Txs:            make([]*common.L2Tx, 0),
 		createdAccounts:  make([]*common.Account, 0),
-		exitTree:         make([]*common.ExitInfo, 0),
+		exitTree:         make([]common.ExitInfo, 0),
 	}
 }
 
@@ -435,7 +435,7 @@ // Get exitTree
 		// TODO: Get createdAccounts from ProcessTxs()
 		// TODO: Get CollectedFees from ProcessTxs()
 		// TODO: Pass forgeBatchArgs.FeeIdxCoordinator to ProcessTxs()
-		_, exitInfo, err := s.stateDB.ProcessTxs(true, false, batchData.l1UserTxs, batchData.l1CoordinatorTxs, poolL2Txs)
+		_, exitInfo, err := s.stateDB.ProcessTxs(batchData.l1UserTxs, batchData.l1CoordinatorTxs, poolL2Txs)
 		if err != nil {
 			return nil, err
 		}

@@ -19,7 +19,7 @@ // Int State DB
 	dir, err := ioutil.TempDir("", "tmpdb")
 	require.Nil(t, err)
 
-	sdb, err := statedb.NewStateDB(dir, true, 32)
+	sdb, err := statedb.NewStateDB(dir, statedb.TypeSynchronizer, 32)
 	assert.Nil(t, err)
 
 	// Init History DB

@@ -43,7 +43,7 @@ }
 
 // NewTxSelector returns a *TxSelector
 func NewTxSelector(dbpath string, synchronizerStateDB *statedb.StateDB, l2 *l2db.L2DB, maxL1UserTxs, maxL1OperatorTxs, maxTxs uint64) (*TxSelector, error) {
-	localAccountsDB, err := statedb.NewLocalStateDB(dbpath, synchronizerStateDB, false, 0) // without merkletree
+	localAccountsDB, err := statedb.NewLocalStateDB(dbpath, synchronizerStateDB, statedb.TypeTxSelector, 0) // without merkletree
 	if err != nil {
 		return nil, err
 	}
@@ -89,7 +89,7 @@ // get most profitable L2-tx
 	txs := txsel.getL2Profitable(validTxs, txsel.MaxTxs)
 
 	// process the txs in the local AccountsDB
-	_, _, err = txsel.localAccountsDB.ProcessTxs(false, false, nil, nil, txs)
+	_, _, err = txsel.localAccountsDB.ProcessTxs(nil, nil, txs)
 	if err != nil {
 		return nil, err
 	}
@@ -238,7 +238,7 @@ maxL2Txs := txsel.MaxTxs - uint64(len(l1CoordinatorTxs)) // - len(l1UserTxs)
 	l2Txs := txsel.getL2Profitable(validTxs, maxL2Txs)
 
 	// process the txs in the local AccountsDB
-	_, _, err = txsel.localAccountsDB.ProcessTxs(false, false, l1Txs, l1CoordinatorTxs, l2Txs)
+	_, _, err = txsel.localAccountsDB.ProcessTxs(l1Txs, l1CoordinatorTxs, l2Txs)
 	if err != nil {
 		return nil, nil, nil, err
 	}

@@ -25,7 +25,7 @@ l2DB := l2db.NewL2DB(db, 10, 100, 24*time.Hour)
 
 	dir, err := ioutil.TempDir("", "tmpdb")
 	require.Nil(t, err)
-	sdb, err := statedb.NewStateDB(dir, false, 0)
+	sdb, err := statedb.NewStateDB(dir, statedb.TypeTxSelector, 0)
 	require.Nil(t, err)
 
 	txselDir, err := ioutil.TempDir("", "tmpTxSelDB")