diff --git a/common/l1tx.go b/common/l1tx.go
index 8351476..e4018cf 100644
--- a/common/l1tx.go
+++ b/common/l1tx.go
@@ -50,74 +50,88 @@ type L1Tx struct {
 
 // NewL1Tx returns the given L1Tx with the TxId & Type parameters calculated
 // from the L1Tx values
-func NewL1Tx(l1Tx *L1Tx) (*L1Tx, error) {
-	// calculate TxType
-	var txType TxType
-	if l1Tx.FromIdx == 0 {
-		if l1Tx.ToIdx == Idx(0) {
-			txType = TxTypeCreateAccountDeposit
-		} else if l1Tx.ToIdx >= IdxUserThreshold {
-			txType = TxTypeCreateAccountDepositTransfer
+func NewL1Tx(tx *L1Tx) (*L1Tx, error) {
+	txTypeOld := tx.Type
+	if err := tx.SetType(); err != nil {
+		return nil, err
+	}
+	// If original Type doesn't match the correct one, return error
+	if txTypeOld != "" && txTypeOld != tx.Type {
+		return nil, tracerr.Wrap(fmt.Errorf("L1Tx.Type: %s, should be: %s",
+			tx.Type, txTypeOld))
+	}
+
+	txIDOld := tx.TxID
+	if err := tx.SetID(); err != nil {
+		return nil, err
+	}
+	// If original TxID doesn't match the correct one, return error
+	if txIDOld != (TxID{}) && txIDOld != tx.TxID {
+		return tx, tracerr.Wrap(fmt.Errorf("L1Tx.TxID: %s, should be: %s",
+			tx.TxID.String(), txIDOld.String()))
+	}
+
+	return tx, nil
+}
+
+// SetType sets the type of the transaction
+func (tx *L1Tx) SetType() error {
+	if tx.FromIdx == 0 {
+		if tx.ToIdx == Idx(0) {
+			tx.Type = TxTypeCreateAccountDeposit
+		} else if tx.ToIdx >= IdxUserThreshold {
+			tx.Type = TxTypeCreateAccountDepositTransfer
 		} else {
-			return l1Tx, tracerr.Wrap(fmt.Errorf("Can not determine type of L1Tx, invalid ToIdx value: %d", l1Tx.ToIdx))
+			return tracerr.Wrap(fmt.Errorf(
+				"Can not determine type of L1Tx, invalid ToIdx value: %d", tx.ToIdx))
 		}
-	} else if l1Tx.FromIdx >= IdxUserThreshold {
-		if l1Tx.ToIdx == Idx(0) {
-			txType = TxTypeDeposit
-		} else if l1Tx.ToIdx == Idx(1) {
-			txType = TxTypeForceExit
-		} else if l1Tx.ToIdx >= IdxUserThreshold {
-			if l1Tx.DepositAmount.Int64() == int64(0) {
-				txType = TxTypeForceTransfer
+	} else if tx.FromIdx >= IdxUserThreshold {
+		if tx.ToIdx == Idx(0) {
+			tx.Type = TxTypeDeposit
+		} else if tx.ToIdx == Idx(1) {
+			tx.Type = TxTypeForceExit
+		} else if tx.ToIdx >= IdxUserThreshold {
+			if tx.DepositAmount.Int64() == int64(0) {
+				tx.Type = TxTypeForceTransfer
 			} else {
-				txType = TxTypeDepositTransfer
+				tx.Type = TxTypeDepositTransfer
 			}
 		} else {
-			return l1Tx, tracerr.Wrap(fmt.Errorf("Can not determine type of L1Tx, invalid ToIdx value: %d", l1Tx.ToIdx))
+			return tracerr.Wrap(fmt.Errorf(
+				"Can not determine type of L1Tx, invalid ToIdx value: %d", tx.ToIdx))
 		}
 	} else {
-		return l1Tx, tracerr.Wrap(fmt.Errorf("Can not determine type of L1Tx, invalid FromIdx value: %d", l1Tx.FromIdx))
-	}
-
-	if l1Tx.Type != "" && l1Tx.Type != txType {
-		return l1Tx, tracerr.Wrap(fmt.Errorf("L1Tx.Type: %s, should be: %s", l1Tx.Type, txType))
-	}
-	l1Tx.Type = txType
-
-	txID, err := l1Tx.CalcTxID()
-	if err != nil {
-		return nil, tracerr.Wrap(err)
+		return tracerr.Wrap(fmt.Errorf(
+			"Can not determine type of L1Tx, invalid FromIdx value: %d", tx.FromIdx))
 	}
-	l1Tx.TxID = *txID
-
-	return l1Tx, nil
+	return nil
 }
 
-// CalcTxID calculates the TxId of the L1Tx
-func (tx *L1Tx) CalcTxID() (*TxID, error) {
-	var txID TxID
+// SetID sets the ID of the transaction.  For L1UserTx uses (ToForgeL1TxsNum,
+// Position), for L1CoordinatorTx uses (BatchNum, Position).
+func (tx *L1Tx) SetID() error {
 	if tx.UserOrigin {
 		if tx.ToForgeL1TxsNum == nil {
-			return nil, tracerr.Wrap(fmt.Errorf("L1Tx.UserOrigin == true && L1Tx.ToForgeL1TxsNum == nil"))
+			return tracerr.Wrap(fmt.Errorf("L1Tx.UserOrigin == true && L1Tx.ToForgeL1TxsNum == nil"))
 		}
-		txID[0] = TxIDPrefixL1UserTx
+		tx.TxID[0] = TxIDPrefixL1UserTx
 		var toForgeL1TxsNumBytes [8]byte
 		binary.BigEndian.PutUint64(toForgeL1TxsNumBytes[:], uint64(*tx.ToForgeL1TxsNum))
-		copy(txID[1:9], toForgeL1TxsNumBytes[:])
+		copy(tx.TxID[1:9], toForgeL1TxsNumBytes[:])
 	} else {
 		if tx.BatchNum == nil {
-			return nil, tracerr.Wrap(fmt.Errorf("L1Tx.UserOrigin == false && L1Tx.BatchNum == nil"))
+			return tracerr.Wrap(fmt.Errorf("L1Tx.UserOrigin == false && L1Tx.BatchNum == nil"))
 		}
-		txID[0] = TxIDPrefixL1CoordTx
+		tx.TxID[0] = TxIDPrefixL1CoordTx
 		var batchNumBytes [8]byte
 		binary.BigEndian.PutUint64(batchNumBytes[:], uint64(*tx.BatchNum))
-		copy(txID[1:9], batchNumBytes[:])
+		copy(tx.TxID[1:9], batchNumBytes[:])
 	}
 	var positionBytes [2]byte
 	binary.BigEndian.PutUint16(positionBytes[:], uint16(tx.Position))
-	copy(txID[9:11], positionBytes[:])
+	copy(tx.TxID[9:11], positionBytes[:])
 
-	return &txID, nil
+	return nil
 }
 
 // Tx returns a *Tx from the L1Tx
diff --git a/common/l2tx.go b/common/l2tx.go
index da78bd0..8a197ad 100644
--- a/common/l2tx.go
+++ b/common/l2tx.go
@@ -24,38 +24,57 @@ type L2Tx struct {
 
 // NewL2Tx returns the given L2Tx with the TxId & Type parameters calculated
 // from the L2Tx values
-func NewL2Tx(l2Tx *L2Tx) (*L2Tx, error) {
-	// calculate TxType
-	var txType TxType
-	if l2Tx.ToIdx == Idx(1) {
-		txType = TxTypeExit
-	} else if l2Tx.ToIdx >= IdxUserThreshold {
-		txType = TxTypeTransfer
-	} else {
-		return l2Tx, tracerr.Wrap(fmt.Errorf("Can not determine type of L2Tx, invalid ToIdx value: %d", l2Tx.ToIdx))
+func NewL2Tx(tx *L2Tx) (*L2Tx, error) {
+	txTypeOld := tx.Type
+	if err := tx.SetType(); err != nil {
+		return nil, err
+	}
+	// If original Type doesn't match the correct one, return error
+	if txTypeOld != "" && txTypeOld != tx.Type {
+		return nil, tracerr.Wrap(fmt.Errorf("L2Tx.Type: %s, should be: %s",
+			tx.Type, txTypeOld))
+	}
+
+	txIDOld := tx.TxID
+	if err := tx.SetID(); err != nil {
+		return nil, err
+	}
+	// If original TxID doesn't match the correct one, return error
+	if txIDOld != (TxID{}) && txIDOld != tx.TxID {
+		return tx, tracerr.Wrap(fmt.Errorf("L2Tx.TxID: %s, should be: %s",
+			tx.TxID.String(), txIDOld.String()))
 	}
 
-	// if TxType!=l2Tx.TxType return error
-	if l2Tx.Type != "" && l2Tx.Type != txType {
-		return l2Tx, tracerr.Wrap(fmt.Errorf("L2Tx.Type: %s, should be: %s", l2Tx.Type, txType))
+	return tx, nil
+}
+
+// SetType sets the type of the transaction.  Uses (FromIdx, Nonce).
+func (tx *L2Tx) SetType() error {
+	if tx.ToIdx == Idx(1) {
+		tx.Type = TxTypeExit
+	} else if tx.ToIdx >= IdxUserThreshold {
+		tx.Type = TxTypeTransfer
+	} else {
+		return tracerr.Wrap(fmt.Errorf(
+			"cannot determine type of L2Tx, invalid ToIdx value: %d", tx.ToIdx))
 	}
-	l2Tx.Type = txType
+	return nil
+}
 
-	var txid [TxIDLen]byte
-	txid[0] = TxIDPrefixL2Tx
-	fromIdxBytes, err := l2Tx.FromIdx.Bytes()
+// SetID sets the ID of the transaction
+func (tx *L2Tx) SetID() error {
+	tx.TxID[0] = TxIDPrefixL2Tx
+	fromIdxBytes, err := tx.FromIdx.Bytes()
 	if err != nil {
-		return l2Tx, tracerr.Wrap(err)
+		return tracerr.Wrap(err)
 	}
-	copy(txid[1:7], fromIdxBytes[:])
-	nonceBytes, err := l2Tx.Nonce.Bytes()
+	copy(tx.TxID[1:7], fromIdxBytes[:])
+	nonceBytes, err := tx.Nonce.Bytes()
 	if err != nil {
-		return l2Tx, tracerr.Wrap(err)
+		return tracerr.Wrap(err)
 	}
-	copy(txid[7:12], nonceBytes[:])
-	l2Tx.TxID = TxID(txid)
-
-	return l2Tx, nil
+	copy(tx.TxID[7:12], nonceBytes[:])
+	return nil
 }
 
 // Tx returns a *Tx from the L2Tx
diff --git a/common/pooll2tx.go b/common/pooll2tx.go
index d52c85e..b256768 100644
--- a/common/pooll2tx.go
+++ b/common/pooll2tx.go
@@ -50,49 +50,62 @@ type PoolL2Tx struct {
 
 // NewPoolL2Tx returns the given L2Tx with the TxId & Type parameters calculated
 // from the L2Tx values
-func NewPoolL2Tx(poolL2Tx *PoolL2Tx) (*PoolL2Tx, error) {
-	// calculate TxType
-	var txType TxType
-	if poolL2Tx.ToIdx >= IdxUserThreshold {
-		txType = TxTypeTransfer
-	} else if poolL2Tx.ToIdx == 1 {
-		txType = TxTypeExit
-	} else if poolL2Tx.ToIdx == 0 {
-		if poolL2Tx.ToBJJ != nil && poolL2Tx.ToEthAddr == FFAddr {
-			txType = TxTypeTransferToBJJ
-		} else if poolL2Tx.ToEthAddr != FFAddr && poolL2Tx.ToEthAddr != EmptyAddr {
-			txType = TxTypeTransferToEthAddr
-		}
-	} else {
-		return nil, tracerr.Wrap(errors.New("malformed transaction"))
+func NewPoolL2Tx(tx *PoolL2Tx) (*PoolL2Tx, error) {
+	txTypeOld := tx.Type
+	if err := tx.SetType(); err != nil {
+		return nil, err
+	}
+	// If original Type doesn't match the correct one, return error
+	if txTypeOld != "" && txTypeOld != tx.Type {
+		return nil, tracerr.Wrap(fmt.Errorf("L2Tx.Type: %s, should be: %s",
+			tx.Type, txTypeOld))
 	}
 
-	// if TxType!=poolL2Tx.TxType return error
-	if poolL2Tx.Type != "" && poolL2Tx.Type != txType {
-		return poolL2Tx, tracerr.Wrap(fmt.Errorf("type: %s, should be: %s", poolL2Tx.Type, txType))
+	txIDOld := tx.TxID
+	if err := tx.SetID(); err != nil {
+		return nil, err
+	}
+	// If original TxID doesn't match the correct one, return error
+	if txIDOld != (TxID{}) && txIDOld != tx.TxID {
+		return tx, tracerr.Wrap(fmt.Errorf("PoolL2Tx.TxID: %s, should be: %s",
+			tx.TxID.String(), txIDOld.String()))
 	}
-	poolL2Tx.Type = txType
 
-	var txid [TxIDLen]byte
-	txid[0] = TxIDPrefixL2Tx
-	fromIdxBytes, err := poolL2Tx.FromIdx.Bytes()
-	if err != nil {
-		return poolL2Tx, tracerr.Wrap(err)
+	return tx, nil
+}
+
+// SetType sets the type of the transaction
+func (tx *PoolL2Tx) SetType() error {
+	if tx.ToIdx >= IdxUserThreshold {
+		tx.Type = TxTypeTransfer
+	} else if tx.ToIdx == 1 {
+		tx.Type = TxTypeExit
+	} else if tx.ToIdx == 0 {
+		if tx.ToBJJ != nil && tx.ToEthAddr == FFAddr {
+			tx.Type = TxTypeTransferToBJJ
+		} else if tx.ToEthAddr != FFAddr && tx.ToEthAddr != EmptyAddr {
+			tx.Type = TxTypeTransferToEthAddr
+		}
+	} else {
+		return tracerr.Wrap(errors.New("malformed transaction"))
 	}
-	copy(txid[1:7], fromIdxBytes[:])
-	nonceBytes, err := poolL2Tx.Nonce.Bytes()
+	return nil
+}
+
+// SetID sets the ID of the transaction.  Uses (FromIdx, Nonce).
+func (tx *PoolL2Tx) SetID() error {
+	tx.TxID[0] = TxIDPrefixL2Tx
+	fromIdxBytes, err := tx.FromIdx.Bytes()
 	if err != nil {
-		return poolL2Tx, tracerr.Wrap(err)
+		return tracerr.Wrap(err)
 	}
-	copy(txid[7:12], nonceBytes[:])
-	txID := TxID(txid)
-
-	// if TxID!=poolL2Tx.TxID return error
-	if poolL2Tx.TxID != (TxID{}) && poolL2Tx.TxID != txID {
-		return poolL2Tx, tracerr.Wrap(fmt.Errorf("id: %s, should be: %s", poolL2Tx.TxID.String(), txID.String()))
+	copy(tx.TxID[1:7], fromIdxBytes[:])
+	nonceBytes, err := tx.Nonce.Bytes()
+	if err != nil {
+		return tracerr.Wrap(err)
 	}
-	poolL2Tx.TxID = txID
-	return poolL2Tx, nil
+	copy(tx.TxID[7:12], nonceBytes[:])
+	return nil
 }
 
 // TxCompressedData spec:
@@ -305,11 +318,11 @@ func (tx PoolL2Tx) Tx() Tx {
 
 // PoolL2TxsToL2Txs returns an array of []L2Tx from an array of []PoolL2Tx
 func PoolL2TxsToL2Txs(txs []PoolL2Tx) ([]L2Tx, error) {
-	var r []L2Tx
-	for _, poolTx := range txs {
-		r = append(r, poolTx.L2Tx())
+	l2Txs := make([]L2Tx, len(txs))
+	for i, poolTx := range txs {
+		l2Txs[i] = poolTx.L2Tx()
 	}
-	return r, nil
+	return l2Txs, nil
 }
 
 // PoolL2TxState is a struct that represents the status of a L2 transaction
diff --git a/db/historydb/historydb_test.go b/db/historydb/historydb_test.go
index e0d1552..0546f43 100644
--- a/db/historydb/historydb_test.go
+++ b/db/historydb/historydb_test.go
@@ -144,9 +144,9 @@ func TestBatches(t *testing.T) {
 		CoordUser:     "A",
 	}
 	blocks, err := tc.GenerateBlocks(set)
-	require.Nil(t, err)
+	require.NoError(t, err)
 	err = tc.FillBlocksExtra(blocks, &tilCfgExtra)
-	assert.Nil(t, err)
+	require.NoError(t, err)
 	// Insert to DB
 	batches := []common.Batch{}
 	tokensValue := make(map[common.TokenID]float64)
@@ -365,9 +365,9 @@ func TestTxs(t *testing.T) {
 		CoordUser:     "A",
 	}
 	blocks, err := tc.GenerateBlocks(set)
-	require.Nil(t, err)
+	require.NoError(t, err)
 	err = tc.FillBlocksExtra(blocks, &tilCfgExtra)
-	assert.Nil(t, err)
+	require.NoError(t, err)
 
 	// Sanity check
 	require.Equal(t, 7, len(blocks))
@@ -617,7 +617,7 @@ func TestGetUnforgedL1UserTxs(t *testing.T) {
 	`
 	tc := til.NewContext(128)
 	blocks, err := tc.GenerateBlocks(set)
-	require.Nil(t, err)
+	require.NoError(t, err)
 	// Sanity check
 	require.Equal(t, 1, len(blocks))
 	require.Equal(t, 5, len(blocks[0].Rollup.L1UserTxs))
@@ -626,17 +626,17 @@ func TestGetUnforgedL1UserTxs(t *testing.T) {
 
 	for i := range blocks {
 		err = historyDB.AddBlockSCData(&blocks[i])
-		require.Nil(t, err)
+		require.NoError(t, err)
 	}
 
 	l1UserTxs, err := historyDB.GetUnforgedL1UserTxs(toForgeL1TxsNum)
-	require.Nil(t, err)
+	require.NoError(t, err)
 	assert.Equal(t, 5, len(l1UserTxs))
 	assert.Equal(t, blocks[0].Rollup.L1UserTxs, l1UserTxs)
 
 	// No l1UserTxs for this toForgeL1TxsNum
 	l1UserTxs, err = historyDB.GetUnforgedL1UserTxs(2)
-	require.Nil(t, err)
+	require.NoError(t, err)
 	assert.Equal(t, 0, len(l1UserTxs))
 }
 
@@ -685,9 +685,9 @@ func TestSetInitialSCVars(t *testing.T) {
 	assert.Equal(t, sql.ErrNoRows, tracerr.Unwrap(err))
 	rollup, auction, wDelayer := exampleInitSCVars()
 	err = historyDB.SetInitialSCVars(rollup, auction, wDelayer)
-	require.Nil(t, err)
+	require.NoError(t, err)
 	dbRollup, dbAuction, dbWDelayer, err := historyDB.GetSCVars()
-	assert.Nil(t, err)
+	require.NoError(t, err)
 	require.Equal(t, rollup, dbRollup)
 	require.Equal(t, auction, dbAuction)
 	require.Equal(t, wDelayer, dbWDelayer)
@@ -718,16 +718,16 @@ func TestSetL1UserTxEffectiveAmounts(t *testing.T) {
 		CoordUser:     "A",
 	}
 	blocks, err := tc.GenerateBlocks(set)
-	require.Nil(t, err)
+	require.NoError(t, err)
 	err = tc.FillBlocksExtra(blocks, &tilCfgExtra)
-	assert.Nil(t, err)
+	require.NoError(t, err)
 	err = tc.FillBlocksForgedL1UserTxs(blocks)
-	require.Nil(t, err)
+	require.NoError(t, err)
 
 	// Add only first block so that the L1UserTxs are not marked as forged
 	for i := range blocks[:1] {
 		err = historyDB.AddBlockSCData(&blocks[i])
-		require.Nil(t, err)
+		require.NoError(t, err)
 	}
 	// Add second batch to trigger the update of the batch_num,
 	// while avoiding the implicit call of setL1UserTxEffectiveAmounts
@@ -735,7 +735,7 @@ func TestSetL1UserTxEffectiveAmounts(t *testing.T) {
 	assert.NoError(t, err)
 	err = historyDB.addBatch(historyDB.db, &blocks[1].Rollup.Batches[0].Batch)
 	assert.NoError(t, err)
-	require.Nil(t, err)
+	require.NoError(t, err)
 
 	// Set the Effective{Amount,DepositAmount} of the L1UserTxs that are forged in the second block
 	l1Txs := blocks[1].Rollup.Batches[0].L1UserTxs
@@ -805,14 +805,14 @@ func TestUpdateExitTree(t *testing.T) {
 		CoordUser:     "A",
 	}
 	blocks, err := tc.GenerateBlocks(set)
-	require.Nil(t, err)
+	require.NoError(t, err)
 	err = tc.FillBlocksExtra(blocks, &tilCfgExtra)
-	assert.Nil(t, err)
+	require.NoError(t, err)
 
 	// Add all blocks except for the last two
 	for i := range blocks[:len(blocks)-2] {
 		err = historyDB.AddBlockSCData(&blocks[i])
-		require.Nil(t, err)
+		require.NoError(t, err)
 	}
 
 	// Add withdraws to the second-to-last block, and insert block into the DB
@@ -832,15 +832,15 @@ func TestUpdateExitTree(t *testing.T) {
 			Owner: tc.UsersByIdx[259].Addr, Token: tokenAddr},
 	)
 	err = historyDB.addBlock(historyDB.db, &block.Block)
-	require.Nil(t, err)
+	require.NoError(t, err)
 
 	err = historyDB.updateExitTree(historyDB.db, block.Block.Num,
 		block.Rollup.Withdrawals, block.WDelayer.Withdrawals)
-	require.Nil(t, err)
+	require.NoError(t, err)
 
 	// Check that exits in DB match with the expected values
 	dbExits, err := historyDB.GetAllExits()
-	require.Nil(t, err)
+	require.NoError(t, err)
 	assert.Equal(t, 4, len(dbExits))
 	dbExitsByIdx := make(map[common.Idx]common.ExitInfo)
 	for _, dbExit := range dbExits {
@@ -865,15 +865,15 @@ func TestUpdateExitTree(t *testing.T) {
 			Amount: big.NewInt(80),
 		})
 	err = historyDB.addBlock(historyDB.db, &block.Block)
-	require.Nil(t, err)
+	require.NoError(t, err)
 
 	err = historyDB.updateExitTree(historyDB.db, block.Block.Num,
 		block.Rollup.Withdrawals, block.WDelayer.Withdrawals)
-	require.Nil(t, err)
+	require.NoError(t, err)
 
 	// Check that delayed withdrawn has been set
 	dbExits, err = historyDB.GetAllExits()
-	require.Nil(t, err)
+	require.NoError(t, err)
 	for _, dbExit := range dbExits {
 		dbExitsByIdx[dbExit.AccountIdx] = dbExit
 	}
@@ -885,16 +885,16 @@ func TestGetBestBidCoordinator(t *testing.T) {
 
 	rollup, auction, wDelayer := exampleInitSCVars()
 	err := historyDB.SetInitialSCVars(rollup, auction, wDelayer)
-	require.Nil(t, err)
+	require.NoError(t, err)
 
 	tc := til.NewContext(common.RollupConstMaxL1UserTx)
 	blocks, err := tc.GenerateBlocks(`
 		Type: Blockchain
 		> block // blockNum=2
 	`)
-	require.Nil(t, err)
+	require.NoError(t, err)
 	err = historyDB.AddBlockSCData(&blocks[0])
-	require.Nil(t, err)
+	require.NoError(t, err)
 
 	coords := []common.Coordinator{
 		{
@@ -911,7 +911,7 @@ func TestGetBestBidCoordinator(t *testing.T) {
 		},
 	}
 	err = historyDB.addCoordinators(historyDB.db, coords)
-	require.Nil(t, err)
+	require.NoError(t, err)
 	err = historyDB.addBids(historyDB.db, []common.Bid{
 		{
 			SlotNum:     10,
@@ -926,10 +926,10 @@ func TestGetBestBidCoordinator(t *testing.T) {
 			Bidder:      coords[1].Bidder,
 		},
 	})
-	require.Nil(t, err)
+	require.NoError(t, err)
 
 	forger10, err := historyDB.GetBestBidCoordinator(10)
-	require.Nil(t, err)
+	require.NoError(t, err)
 	require.Equal(t, coords[1].Forger, forger10.Forger)
 	require.Equal(t, coords[1].Bidder, forger10.Bidder)
 	require.Equal(t, coords[1].URL, forger10.URL)
diff --git a/synchronizer/synchronizer.go b/synchronizer/synchronizer.go
index 1f4d707..ae77941 100644
--- a/synchronizer/synchronizer.go
+++ b/synchronizer/synchronizer.go
@@ -753,13 +753,11 @@ func (s *Synchronizer) rollupSync(ethBlock *common.Block) (*common.RollupData, e
 		// L1CoordinatorTxs, PoolL2Txs) into stateDB so that they are
 		// processed.
 
-		// Add TxID, TxType, Position, BlockNum and BatchNum to L2 txs
+		// Set TxType to the forged L2Txs
 		for i := range forgeBatchArgs.L2TxsData {
-			nTx, err := common.NewL2Tx(&forgeBatchArgs.L2TxsData[i])
-			if err != nil {
+			if err := forgeBatchArgs.L2TxsData[i].SetType(); err != nil {
 				return nil, tracerr.Wrap(err)
 			}
-			forgeBatchArgs.L2TxsData[i] = *nTx
 		}
 
 		// Transform L2 txs to PoolL2Txs
@@ -780,19 +778,22 @@ func (s *Synchronizer) rollupSync(ethBlock *common.Block) (*common.RollupData, e
 		}
 
 		// Transform processed PoolL2 txs to L2 and store in BatchData
-		if poolL2Txs != nil {
-			l2Txs, err := common.PoolL2TxsToL2Txs(poolL2Txs) // NOTE: This is a big uggly, find a better way
-			if err != nil {
-				return nil, tracerr.Wrap(err)
-			}
-			for i := range l2Txs {
-				l2Txs[i].Position = position
-				l2Txs[i].EthBlockNum = blockNum
-				l2Txs[i].BatchNum = batchNum
-				position++
+		l2Txs, err := common.PoolL2TxsToL2Txs(poolL2Txs) // NOTE: This is a big uggly, find a better way
+		if err != nil {
+			return nil, tracerr.Wrap(err)
+		}
+
+		// Set TxID, BlockNum, BatchNum and Position to the forged L2Txs
+		for i := range l2Txs {
+			if err := l2Txs[i].SetID(); err != nil {
+				return nil, err
 			}
-			batchData.L2Txs = l2Txs
+			l2Txs[i].EthBlockNum = blockNum
+			l2Txs[i].BatchNum = batchNum
+			l2Txs[i].Position = position
+			position++
 		}
+		batchData.L2Txs = l2Txs
 
 		// Set the BatchNum in the forged L1UserTxs
 		for i := range l1UserTxs {
diff --git a/test/til/txs.go b/test/til/txs.go
index b8ae1ec..889e5f6 100644
--- a/test/til/txs.go
+++ b/test/til/txs.go
@@ -882,6 +882,9 @@ func (tc *Context) FillBlocksExtra(blocks []common.BlockData, cfg *ConfigExtra)
 				position++
 				tc.extra.nonces[tx.FromIdx]++
 				tx.Nonce = tc.extra.nonces[tx.FromIdx]
+				if err := tx.SetID(); err != nil {
+					return err
+				}
 				nTx, err := common.NewL2Tx(tx)
 				if err != nil {
 					return tracerr.Wrap(err)