diff --git a/filemanager/gcsmanager.go b/filemanager/gcsmanager.go
index 5c3db627..9b761742 100644
--- a/filemanager/gcsmanager.go
+++ b/filemanager/gcsmanager.go
@@ -8,6 +8,7 @@ import (
 	"os"
 	"path"
 	"strings"
+	"sync"
 	"time"
 
 	"google.golang.org/api/iterator"
@@ -30,7 +31,9 @@ type GCSConfig struct {
 }
 
 // NewGCSManager creates a new file manager for Google Cloud Storage
-func NewGCSManager(config map[string]interface{}, log logger.Logger, defaultTimeout func() time.Duration) (*gcsManager, error) {
+func NewGCSManager(
+	config map[string]interface{}, log logger.Logger, defaultTimeout func() time.Duration,
+) (*gcsManager, error) {
 	return &gcsManager{
 		baseManager: &baseManager{
 			logger:         log,
@@ -40,7 +43,7 @@ func NewGCSManager(config map[string]interface{}, log logger.Logger, defaultTime
 	}, nil
 }
 
-func (manager *gcsManager) ListFilesWithPrefix(ctx context.Context, startAfter, prefix string, maxItems int64) ListSession {
+func (m *gcsManager) ListFilesWithPrefix(ctx context.Context, startAfter, prefix string, maxItems int64) ListSession {
 	return &gcsListSession{
 		baseListSession: &baseListSession{
 			ctx:        ctx,
@@ -48,41 +51,41 @@ func (manager *gcsManager) ListFilesWithPrefix(ctx context.Context, startAfter,
 			prefix:     prefix,
 			maxItems:   maxItems,
 		},
-		manager: manager,
+		manager: m,
 	}
 }
 
-func (manager *gcsManager) Download(ctx context.Context, output *os.File, key string) error {
-	client, err := manager.getClient(ctx)
+func (m *gcsManager) Download(ctx context.Context, output *os.File, key string) error {
+	client, err := m.getClient(ctx)
 	if err != nil {
 		return err
 	}
 
-	ctx, cancel := context.WithTimeout(ctx, manager.getTimeout())
+	ctx, cancel := context.WithTimeout(ctx, m.getTimeout())
 	defer cancel()
 
-	rc, err := client.Bucket(manager.config.Bucket).Object(key).NewReader(ctx)
+	rc, err := client.Bucket(m.config.Bucket).Object(key).NewReader(ctx)
 	if err != nil {
 		return err
 	}
-	defer rc.Close()
+	defer func() { _ = rc.Close() }()
 
 	_, err = io.Copy(output, rc)
 	return err
 }
 
-func (manager *gcsManager) Upload(ctx context.Context, file *os.File, prefixes ...string) (UploadedFile, error) {
-	fileName := path.Join(manager.config.Prefix, path.Join(prefixes...), path.Base(file.Name()))
+func (m *gcsManager) Upload(ctx context.Context, file *os.File, prefixes ...string) (UploadedFile, error) {
+	fileName := path.Join(m.config.Prefix, path.Join(prefixes...), path.Base(file.Name()))
 
-	client, err := manager.getClient(ctx)
+	client, err := m.getClient(ctx)
 	if err != nil {
 		return UploadedFile{}, err
 	}
 
-	ctx, cancel := context.WithTimeout(ctx, manager.getTimeout())
+	ctx, cancel := context.WithTimeout(ctx, m.getTimeout())
 	defer cancel()
 
-	obj := client.Bucket(manager.config.Bucket).Object(fileName)
+	obj := client.Bucket(m.config.Bucket).Object(fileName)
 	w := obj.NewWriter(ctx)
 	if _, err := io.Copy(w, file); err != nil {
 		err = fmt.Errorf("copying file to GCS: %v", err)
@@ -98,82 +101,86 @@ func (manager *gcsManager) Upload(ctx context.Context, file *os.File, prefixes .
 	}
 	attrs := w.Attrs()
 
-	return UploadedFile{Location: manager.objectURL(attrs), ObjectName: fileName}, err
+	return UploadedFile{Location: m.objectURL(attrs), ObjectName: fileName}, err
 }
 
-func (manager *gcsManager) Delete(ctx context.Context, keys []string) (err error) {
-	client, err := manager.getClient(ctx)
+func (m *gcsManager) Delete(ctx context.Context, keys []string) (err error) {
+	client, err := m.getClient(ctx)
 	if err != nil {
 		return err
 	}
 
-	ctx, cancel := context.WithTimeout(ctx, manager.getTimeout())
+	ctx, cancel := context.WithTimeout(ctx, m.getTimeout())
 	defer cancel()
 
 	for _, key := range keys {
-		if err := client.Bucket(manager.config.Bucket).Object(key).Delete(ctx); err != nil && !errors.Is(err, storage.ErrObjectNotExist) {
+		if err := client.Bucket(m.config.Bucket).Object(key).Delete(ctx); err != nil && !errors.Is(err, storage.ErrObjectNotExist) {
 			return err
 		}
 	}
 	return
 }
 
-func (manager *gcsManager) Prefix() string {
-	return manager.config.Prefix
+func (m *gcsManager) Prefix() string {
+	return m.config.Prefix
 }
 
-func (manager *gcsManager) GetObjectNameFromLocation(location string) (string, error) {
-	splitStr := strings.Split(location, manager.config.Bucket)
+func (m *gcsManager) GetObjectNameFromLocation(location string) (string, error) {
+	splitStr := strings.Split(location, m.config.Bucket)
 	object := strings.TrimLeft(splitStr[len(splitStr)-1], "/")
 	return object, nil
 }
 
-func (manager *gcsManager) GetDownloadKeyFromFileLocation(location string) string {
-	splitStr := strings.Split(location, manager.config.Bucket)
+func (m *gcsManager) GetDownloadKeyFromFileLocation(location string) string {
+	splitStr := strings.Split(location, m.config.Bucket)
 	key := strings.TrimLeft(splitStr[len(splitStr)-1], "/")
 	return key
 }
 
-func (manager *gcsManager) objectURL(objAttrs *storage.ObjectAttrs) string {
-	if manager.config.EndPoint != nil && *manager.config.EndPoint != "" {
-		endpoint := strings.TrimSuffix(*manager.config.EndPoint, "/")
+func (m *gcsManager) objectURL(objAttrs *storage.ObjectAttrs) string {
+	if m.config.EndPoint != nil && *m.config.EndPoint != "" {
+		endpoint := strings.TrimSuffix(*m.config.EndPoint, "/")
 		return fmt.Sprintf("%s/%s/%s", endpoint, objAttrs.Bucket, objAttrs.Name)
 	}
 	return fmt.Sprintf("https://storage.googleapis.com/%s/%s", objAttrs.Bucket, objAttrs.Name)
 }
 
-func (manager *gcsManager) getClient(ctx context.Context) (*storage.Client, error) {
-	var err error
+func (m *gcsManager) getClient(ctx context.Context) (*storage.Client, error) {
+	m.clientMu.Lock()
+	defer m.clientMu.Unlock()
 
-	ctx, cancel := context.WithTimeout(ctx, manager.getTimeout())
-	defer cancel()
-	if manager.client != nil {
-		return manager.client, err
+	if m.client != nil {
+		return m.client, nil
 	}
-	options := []option.ClientOption{}
 
-	if manager.config.EndPoint != nil && *manager.config.EndPoint != "" {
-		options = append(options, option.WithEndpoint(*manager.config.EndPoint))
+	var options []option.ClientOption
+	if m.config.EndPoint != nil && *m.config.EndPoint != "" {
+		options = append(options, option.WithEndpoint(*m.config.EndPoint))
 	}
-	if !googleutil.ShouldSkipCredentialsInit(manager.config.Credentials) {
-		if err = googleutil.CompatibleGoogleCredentialsJSON([]byte(manager.config.Credentials)); err != nil {
-			return manager.client, err
+	if !googleutil.ShouldSkipCredentialsInit(m.config.Credentials) {
+		if err := googleutil.CompatibleGoogleCredentialsJSON([]byte(m.config.Credentials)); err != nil {
+			return m.client, err
 		}
-		options = append(options, option.WithCredentialsJSON([]byte(manager.config.Credentials)))
+		options = append(options, option.WithCredentialsJSON([]byte(m.config.Credentials)))
 	}
-	if manager.config.JSONReads {
+	if m.config.JSONReads {
 		options = append(options, storage.WithJSONReads())
 	}
 
-	manager.client, err = storage.NewClient(ctx, options...)
-	return manager.client, err
+	ctx, cancel := context.WithTimeout(ctx, m.getTimeout())
+	defer cancel()
+
+	var err error
+	m.client, err = storage.NewClient(ctx, options...)
+	return m.client, err
 }
 
 type gcsManager struct {
 	*baseManager
 	config *GCSConfig
 
-	client *storage.Client
+	client   *storage.Client
+	clientMu sync.Mutex
 }
 
 func gcsConfig(config map[string]interface{}) *GCSConfig {