diff --git a/database/controller.go b/database/controller.go
index 918112b..a9f9d48 100644
--- a/database/controller.go
+++ b/database/controller.go
@@ -138,25 +138,29 @@ func (c *Controller) Put(r record.Record) (err error) {
 }
 
 // PutMany stores many records in the database.
-func (c *Controller) PutMany() (batch chan record.Record, err chan error) {
+func (c *Controller) PutMany() (chan<- record.Record, <-chan error) {
 	c.writeLock.RLock()
 	defer c.writeLock.RUnlock()
 
 	if shuttingDown.IsSet() {
-		batch = make(chan record.Record)
-		err = make(chan error, 1)
-		err <- ErrShuttingDown
-		return
+		errs := make(chan error, 1)
+		errs <- ErrShuttingDown
+		return make(chan record.Record), errs
 	}
 
 	if c.ReadOnly() {
-		batch = make(chan record.Record)
-		err = make(chan error, 1)
-		err <- ErrReadOnly
-		return
+		errs := make(chan error, 1)
+		errs <- ErrReadOnly
+		return make(chan record.Record), errs
 	}
 
-	return c.storage.PutMany()
+	if batcher, ok := c.storage.(storage.Batcher); ok {
+		return batcher.PutMany()
+	}
+
+	errs := make(chan error, 1)
+	errs <- ErrNotImplemented
+	return make(chan record.Record), errs
 }
 
 // Query executes the given query on the database.
diff --git a/database/errors.go b/database/errors.go
index cae280d..9d22b53 100644
--- a/database/errors.go
+++ b/database/errors.go
@@ -10,4 +10,5 @@ var (
 	ErrPermissionDenied = errors.New("access to database record denied")
 	ErrReadOnly         = errors.New("database is read only")
 	ErrShuttingDown     = errors.New("database system is shutting down")
+	ErrNotImplemented   = errors.New("not implemented by this storage")
 )
diff --git a/database/interface.go b/database/interface.go
index 87beccd..a939960 100644
--- a/database/interface.go
+++ b/database/interface.go
@@ -5,6 +5,8 @@ import (
 	"fmt"
 	"time"
 
+	"github.com/tevino/abool"
+
 	"github.com/bluele/gcache"
 
 	"github.com/safing/portbase/database/accessor"
@@ -245,16 +247,18 @@ func (i *Interface) PutMany(dbName string) (put func(record.Record) error) {
 	}
 
 	// start database access
-	dbBatch, errCh := db.PutMany()
+	dbBatch, errs := db.PutMany()
+	finished := abool.New()
+	var internalErr error
 
 	// interface options proxy
 	go func() {
+		defer close(dbBatch) // signify that we are finished
 		for {
 			select {
 			case r := <-interfaceBatch:
 				// finished?
 				if r == nil {
-					close(dbBatch) // signify that we are finished
 					return
 				}
 				// apply options
@@ -263,27 +267,47 @@ func (i *Interface) PutMany(dbName string) (put func(record.Record) error) {
 				dbBatch <- r
 			case <-time.After(1 * time.Second):
 				// bail out
-				errCh <- errors.New("timeout: putmany unused for too long")
-				close(dbBatch) // signify that we are finished
+				internalErr = errors.New("timeout: putmany unused for too long")
+				finished.Set()
 				return
 			}
 		}
 	}()
 
 	return func(r record.Record) error {
-		if r == nil {
-			interfaceBatch <- nil // signify that we are finished
-			// do not close, as this fn could be called again with nil.
-			return <-errCh
+		// finished?
+		if finished.IsSet() {
+			// check for internal error
+			if internalErr != nil {
+				return internalErr
+			}
+			// check for previous error
+			select {
+			case err := <-errs:
+				return err
+			default:
+				return errors.New("batch is closed")
+			}
 		}
 
+		// finish?
+		if r == nil {
+			finished.Set()
+			interfaceBatch <- nil // signify that we are finished
+			// do not close, as this fn could be called again with nil.
+			return <-errs
+		}
+
+		// check record scope
 		if r.DatabaseName() != dbName {
 			return errors.New("record out of database scope")
 		}
+
+		// submit
 		select {
 		case interfaceBatch <- r:
 			return nil
-		case err := <-errCh:
+		case err := <-errs:
 			return err
 		}
 	}
diff --git a/database/storage/badger/badger.go b/database/storage/badger/badger.go
index 8f2c9f3..8f473cd 100644
--- a/database/storage/badger/badger.go
+++ b/database/storage/badger/badger.go
@@ -94,15 +94,6 @@ func (b *Badger) Put(r record.Record) error {
 	return err
 }
 
-// PutMany stores many records in the database.
-func (b *Badger) PutMany() (batch chan record.Record, err chan error) {
-	// TODO: implement PutMany
-	batch = make(chan record.Record)
-	err = make(chan error, 1)
-	err <- errors.New("not implemented")
-	return
-}
-
 // Delete deletes a record from the database.
 func (b *Badger) Delete(key string) error {
 	return b.db.Update(func(txn *badger.Txn) error {
diff --git a/database/storage/bbolt/bbolt.go b/database/storage/bbolt/bbolt.go
index 832c157..bb049a9 100644
--- a/database/storage/bbolt/bbolt.go
+++ b/database/storage/bbolt/bbolt.go
@@ -106,20 +106,14 @@ func (b *BBolt) Put(r record.Record) error {
 }
 
 // PutMany stores many records in the database.
-func (b *BBolt) PutMany() (batch chan record.Record, errCh chan error) {
-	batch = make(chan record.Record, 100)
-	errCh = make(chan error, 1)
+func (b *BBolt) PutMany() (chan<- record.Record, <-chan error) {
+	batch := make(chan record.Record, 100)
+	errs := make(chan error, 1)
 
 	go func() {
 		err := b.db.Batch(func(tx *bbolt.Tx) error {
 			bucket := tx.Bucket(bucketName)
-			for {
-				r := <-batch
-				// finished?
-				if r == nil {
-					return nil
-				}
-
+			for r := range batch {
 				// marshal
 				data, txErr := r.MarshalRecord(r)
 				if txErr != nil {
@@ -132,11 +126,12 @@ func (b *BBolt) PutMany() (batch chan record.Record, errCh chan error) {
 					return txErr
 				}
 			}
+			return nil
 		})
-		errCh <- err
+		errs <- err
 	}()
 
-	return batch, errCh
+	return batch, errs
 }
 
 // Delete deletes a record from the database.
diff --git a/database/storage/fstree/fstree.go b/database/storage/fstree/fstree.go
index 654695f..fa160de 100644
--- a/database/storage/fstree/fstree.go
+++ b/database/storage/fstree/fstree.go
@@ -131,15 +131,6 @@ func (fst *FSTree) Put(r record.Record) error {
 	return nil
 }
 
-// PutMany stores many records in the database.
-func (fst *FSTree) PutMany() (batch chan record.Record, err chan error) {
-	// TODO: implement PutMany
-	batch = make(chan record.Record)
-	err = make(chan error, 1)
-	err <- errors.New("not implemented")
-	return
-}
-
 // Delete deletes a record from the database.
 func (fst *FSTree) Delete(key string) error {
 	dstPath, err := fst.buildFilePath(key, true)
diff --git a/database/storage/hashmap/map.go b/database/storage/hashmap/map.go
index 8e1103a..d9fa3df 100644
--- a/database/storage/hashmap/map.go
+++ b/database/storage/hashmap/map.go
@@ -53,30 +53,24 @@ func (hm *HashMap) Put(r record.Record) error {
 }
 
 // PutMany stores many records in the database.
-func (hm *HashMap) PutMany() (batch chan record.Record, err chan error) {
+func (hm *HashMap) PutMany() (chan<- record.Record, <-chan error) {
 	hm.dbLock.Lock()
 	defer hm.dbLock.Unlock()
 	// we could lock for every record, but we want to have the same behaviour
 	// as the other storage backends, especially for testing.
 
-	batch = make(chan record.Record, 100)
-	err = make(chan error, 1)
+	batch := make(chan record.Record, 100)
+	errs := make(chan error, 1)
 
 	// start handler
 	go func() {
-		for {
-			r := <-batch
-			// finished?
-			if r == nil {
-				err <- nil
-				return
-			}
-			// put
+		for r := range batch {
 			hm.db[r.DatabaseKey()] = r
 		}
+		errs <- nil
 	}()
 
-	return
+	return batch, errs
 }
 
 // Delete deletes a record from the database.
diff --git a/database/storage/interface.go b/database/storage/interface.go
index 3f0642a..484f852 100644
--- a/database/storage/interface.go
+++ b/database/storage/interface.go
@@ -10,7 +10,6 @@ import (
 type Interface interface {
 	Get(key string) (record.Record, error)
 	Put(m record.Record) error
-	PutMany() (batch chan record.Record, err chan error)
 	Delete(key string) error
 	Query(q *query.Query, local, internal bool) (*iterator.Iterator, error)
 
@@ -20,3 +19,8 @@ type Interface interface {
 	MaintainThorough() error
 	Shutdown() error
 }
+
+// Batcher defines the database storage API for backends that support batch operations.
+type Batcher interface {
+	PutMany() (batch chan<- record.Record, errs <-chan error)
+}
diff --git a/database/storage/sinkhole/sinkhole.go b/database/storage/sinkhole/sinkhole.go
index 14bbfb0..e26eaa5 100644
--- a/database/storage/sinkhole/sinkhole.go
+++ b/database/storage/sinkhole/sinkhole.go
@@ -41,23 +41,19 @@ func (s *Sinkhole) Put(m record.Record) error {
 }
 
 // PutMany stores many records in the database.
-func (s *Sinkhole) PutMany() (batch chan record.Record, err chan error) {
-	batch = make(chan record.Record, 100)
-	err = make(chan error, 1)
+func (s *Sinkhole) PutMany() (chan<- record.Record, <-chan error) {
+	batch := make(chan record.Record, 100)
+	errs := make(chan error, 1)
 
 	// start handler
 	go func() {
-		for {
-			r := <-batch
-			// finished?
-			if r == nil {
-				err <- nil
-				return
-			}
+		for range batch {
+			// nom, nom, nom
 		}
+		errs <- nil
 	}()
 
-	return
+	return batch, errs
 }
 
 // Delete deletes a record from the database.