diff --git a/syncapi/storage/shared/syncserver.go b/syncapi/storage/shared/syncserver.go
index 320792914..e1312671b 100644
--- a/syncapi/storage/shared/syncserver.go
+++ b/syncapi/storage/shared/syncserver.go
@@ -281,16 +281,16 @@ func (d *Database) WriteEvent(
 			ctx, txn, ev, addStateEventIDs, removeStateEventIDs, transactionID, excludeFromSync,
 		)
 		if err != nil {
-			return err
+			return fmt.Errorf("d.OutputEvents.InsertEvent: %w", err)
 		}
 		pduPosition = pos
 
 		if err = d.Topology.InsertEventInTopology(ctx, txn, ev, pos); err != nil {
-			return err
+			return fmt.Errorf("d.Topology.InsertEventInTopology: %w", err)
 		}
 
 		if err = d.handleBackwardExtremities(ctx, txn, ev); err != nil {
-			return err
+			return fmt.Errorf("d.handleBackwardExtremities: %w", err)
 		}
 
 		if len(addStateEvents) == 0 && len(removeStateEventIDs) == 0 {
@@ -313,7 +313,7 @@ func (d *Database) updateRoomState(
 	// remove first, then add, as we do not ever delete state, but do replace state which is a remove followed by an add.
 	for _, eventID := range removedEventIDs {
 		if err := d.CurrentRoomState.DeleteRoomStateByEventID(ctx, txn, eventID); err != nil {
-			return err
+			return fmt.Errorf("d.CurrentRoomState.DeleteRoomStateByEventID: %w", err)
 		}
 	}
 
@@ -326,13 +326,13 @@ func (d *Database) updateRoomState(
 		if event.Type() == "m.room.member" {
 			value, err := event.Membership()
 			if err != nil {
-				return err
+				return fmt.Errorf("event.Membership: %w", err)
 			}
 			membership = &value
 		}
 
 		if err := d.CurrentRoomState.UpsertRoomState(ctx, txn, event, membership, pduPosition); err != nil {
-			return err
+			return fmt.Errorf("d.CurrentRoomState.UpsertRoomState: %w", err)
 		}
 	}
 
diff --git a/syncapi/storage/sqlite3/backwards_extremities_table.go b/syncapi/storage/sqlite3/backwards_extremities_table.go
index 25a3047f1..1aeb041f4 100644
--- a/syncapi/storage/sqlite3/backwards_extremities_table.go
+++ b/syncapi/storage/sqlite3/backwards_extremities_table.go
@@ -79,7 +79,7 @@ func NewSqliteBackwardsExtremitiesTable(db *sql.DB) (tables.BackwardsExtremities
 func (s *backwardExtremitiesStatements) InsertsBackwardExtremity(
 	ctx context.Context, txn *sql.Tx, roomID, eventID string, prevEventID string,
 ) (err error) {
-	return s.writer.Do(s.db, nil, func(txn *sql.Tx) error {
+	return s.writer.Do(s.db, txn, func(txn *sql.Tx) error {
 		_, err := txn.Stmt(s.insertBackwardExtremityStmt).ExecContext(ctx, roomID, eventID, prevEventID)
 		return err
 	})
@@ -110,7 +110,7 @@ func (s *backwardExtremitiesStatements) SelectBackwardExtremitiesForRoom(
 func (s *backwardExtremitiesStatements) DeleteBackwardExtremity(
 	ctx context.Context, txn *sql.Tx, roomID, knownEventID string,
 ) (err error) {
-	return s.writer.Do(s.db, nil, func(txn *sql.Tx) error {
+	return s.writer.Do(s.db, txn, func(txn *sql.Tx) error {
 		_, err := txn.Stmt(s.deleteBackwardExtremityStmt).ExecContext(ctx, roomID, knownEventID)
 		return err
 	})
diff --git a/syncapi/storage/sqlite3/current_room_state_table.go b/syncapi/storage/sqlite3/current_room_state_table.go
index 7e579df26..08b42f5b4 100644
--- a/syncapi/storage/sqlite3/current_room_state_table.go
+++ b/syncapi/storage/sqlite3/current_room_state_table.go
@@ -200,7 +200,7 @@ func (s *currentRoomStateStatements) SelectCurrentState(
 func (s *currentRoomStateStatements) DeleteRoomStateByEventID(
 	ctx context.Context, txn *sql.Tx, eventID string,
 ) error {
-	return s.writer.Do(s.db, nil, func(txn *sql.Tx) error {
+	return s.writer.Do(s.db, txn, func(txn *sql.Tx) error {
 		stmt := sqlutil.TxStmt(txn, s.deleteRoomStateByEventIDStmt)
 		_, err := stmt.ExecContext(ctx, eventID)
 		return err
@@ -225,7 +225,7 @@ func (s *currentRoomStateStatements) UpsertRoomState(
 	}
 
 	// upsert state event
-	return s.writer.Do(s.db, nil, func(txn *sql.Tx) error {
+	return s.writer.Do(s.db, txn, func(txn *sql.Tx) error {
 		stmt := sqlutil.TxStmt(txn, s.upsertRoomStateStmt)
 		_, err := stmt.ExecContext(
 			ctx,
diff --git a/syncapi/storage/sqlite3/invites_table.go b/syncapi/storage/sqlite3/invites_table.go
index 0ad038cf8..19e7a7c68 100644
--- a/syncapi/storage/sqlite3/invites_table.go
+++ b/syncapi/storage/sqlite3/invites_table.go
@@ -95,7 +95,7 @@ func NewSqliteInvitesTable(db *sql.DB, streamID *streamIDStatements) (tables.Inv
 func (s *inviteEventsStatements) InsertInviteEvent(
 	ctx context.Context, txn *sql.Tx, inviteEvent gomatrixserverlib.HeaderedEvent,
 ) (streamPos types.StreamPosition, err error) {
-	err = s.writer.Do(s.db, nil, func(txn *sql.Tx) error {
+	err = s.writer.Do(s.db, txn, func(txn *sql.Tx) error {
 		var err error
 		streamPos, err = s.streamIDStatements.nextStreamID(ctx, txn)
 		if err != nil {
diff --git a/syncapi/storage/sqlite3/output_room_events_table.go b/syncapi/storage/sqlite3/output_room_events_table.go
index 16d155834..12b4dbabe 100644
--- a/syncapi/storage/sqlite3/output_room_events_table.go
+++ b/syncapi/storage/sqlite3/output_room_events_table.go
@@ -295,11 +295,6 @@ func (s *outputRoomEventsStatements) InsertEvent(
 		return 0, err
 	}
 
-	streamPos, err := s.streamIDStatements.nextStreamID(ctx, txn)
-	if err != nil {
-		return 0, err
-	}
-
 	addStateJSON, err := json.Marshal(addState)
 	if err != nil {
 		return 0, err
@@ -309,7 +304,13 @@ func (s *outputRoomEventsStatements) InsertEvent(
 		return 0, err
 	}
 
-	err = s.writer.Do(s.db, nil, func(txn *sql.Tx) error {
+	var streamPos types.StreamPosition
+	err = s.writer.Do(s.db, txn, func(txn *sql.Tx) error {
+		streamPos, err = s.streamIDStatements.nextStreamID(ctx, txn)
+		if err != nil {
+			return err
+		}
+
 		insertStmt := sqlutil.TxStmt(txn, s.insertEventStmt)
 		_, ierr := insertStmt.ExecContext(
 			ctx,
diff --git a/syncapi/storage/sqlite3/output_room_events_topology_table.go b/syncapi/storage/sqlite3/output_room_events_topology_table.go
index eb3dcaca6..2e71e8f33 100644
--- a/syncapi/storage/sqlite3/output_room_events_topology_table.go
+++ b/syncapi/storage/sqlite3/output_room_events_topology_table.go
@@ -107,7 +107,7 @@ func NewSqliteTopologyTable(db *sql.DB) (tables.Topology, error) {
 func (s *outputRoomEventsTopologyStatements) InsertEventInTopology(
 	ctx context.Context, txn *sql.Tx, event *gomatrixserverlib.HeaderedEvent, pos types.StreamPosition,
 ) (err error) {
-	return s.writer.Do(s.db, nil, func(txn *sql.Tx) error {
+	return s.writer.Do(s.db, txn, func(txn *sql.Tx) error {
 		stmt := sqlutil.TxStmt(txn, s.insertEventInTopologyStmt)
 		_, err := stmt.ExecContext(
 			ctx, event.EventID(), event.Depth(), event.RoomID(), pos,
diff --git a/syncapi/storage/sqlite3/send_to_device_table.go b/syncapi/storage/sqlite3/send_to_device_table.go
index 317511db6..88b319fb3 100644
--- a/syncapi/storage/sqlite3/send_to_device_table.go
+++ b/syncapi/storage/sqlite3/send_to_device_table.go
@@ -103,7 +103,7 @@ func NewSqliteSendToDeviceTable(db *sql.DB) (tables.SendToDevice, error) {
 func (s *sendToDeviceStatements) InsertSendToDeviceMessage(
 	ctx context.Context, txn *sql.Tx, userID, deviceID, content string,
 ) (err error) {
-	return s.writer.Do(s.db, nil, func(txn *sql.Tx) error {
+	return s.writer.Do(s.db, txn, func(txn *sql.Tx) error {
 		_, err := sqlutil.TxStmt(txn, s.insertSendToDeviceMessageStmt).ExecContext(ctx, userID, deviceID, content)
 		return err
 	})
@@ -163,7 +163,7 @@ func (s *sendToDeviceStatements) UpdateSentSendToDeviceMessages(
 	for k, v := range nids {
 		params[k+1] = v
 	}
-	return s.writer.Do(s.db, nil, func(txn *sql.Tx) error {
+	return s.writer.Do(s.db, txn, func(txn *sql.Tx) error {
 		_, err := txn.ExecContext(ctx, query, params...)
 		return err
 	})
@@ -177,7 +177,7 @@ func (s *sendToDeviceStatements) DeleteSendToDeviceMessages(
 	for k, v := range nids {
 		params[k] = v
 	}
-	return s.writer.Do(s.db, nil, func(txn *sql.Tx) error {
+	return s.writer.Do(s.db, txn, func(txn *sql.Tx) error {
 		_, err := txn.ExecContext(ctx, query, params...)
 		return err
 	})
diff --git a/syncapi/storage/storage_test.go b/syncapi/storage/storage_test.go
index feacbc18c..474d3222b 100644
--- a/syncapi/storage/storage_test.go
+++ b/syncapi/storage/storage_test.go
@@ -5,6 +5,7 @@ import (
 	"crypto/ed25519"
 	"encoding/json"
 	"fmt"
+	"os"
 	"testing"
 	"time"
 
@@ -52,7 +53,13 @@ func MustCreateEvent(t *testing.T, roomID string, prevs []gomatrixserverlib.Head
 }
 
 func MustCreateDatabase(t *testing.T) storage.Database {
-	db, err := sqlite3.NewDatabase("file::memory:")
+	dbname := fmt.Sprintf("test_%s.db", t.Name())
+	if _, err := os.Stat(dbname); err == nil {
+		if err = os.Remove(dbname); err != nil {
+			t.Fatalf("tried to delete stale test database but failed: %s", err)
+		}
+	}
+	db, err := sqlite3.NewDatabase(fmt.Sprintf("file:%s", dbname))
 	if err != nil {
 		t.Fatalf("NewSyncServerDatasource returned %s", err)
 	}