diff --git a/pkg/obiformats/binary_write.go b/pkg/obiformats/binary_write.go
deleted file mode 100644
index d61c2d8..0000000
--- a/pkg/obiformats/binary_write.go
+++ /dev/null
@@ -1,153 +0,0 @@
-package obiformats
-
-import (
-	"io"
-	"log"
-	"os"
-	"time"
-
-	"git.metabarcoding.org/lecasofts/go/obitools/pkg/obiseq"
-	"github.com/renproject/surge"
-)
-
-func WriteBinary(iterator obiseq.IBioSequence, file io.Writer) error {
-	singleseq := make(obiseq.BioSequenceSlice, 1)
-	blob := make([]byte, 0, 1024)
-	for iterator.Next() {
-		singleseq[0] = iterator.Get()
-		blobsize := singleseq.SizeHint()
-		if blobsize > cap(blob) {
-			blob = make([]byte, 0, blobsize*2+8)
-		}
-		_, _, err := surge.MarshalI64(int64(blobsize), blob, 8)
-		if err != nil {
-			return err
-		}
-		data := blob[8 : 8+blobsize]
-		_, _, err = singleseq.Marshal(data, blobsize)
-		if err != nil {
-			return err
-		}
-
-		file.Write(blob[0 : 8+blobsize])
-	}
-
-	return nil
-}
-
-func WriteBinaryToFile(iterator obiseq.IBioSequence,
-	filename string) error {
-
-	file, err := os.Create(filename)
-
-	if err != nil {
-		log.Fatalf("open file error: %v", err)
-		return err
-	}
-
-	return WriteBinary(iterator, file)
-}
-
-func WriteBinaryToStdout(iterator obiseq.IBioSequence) error {
-	return WriteBinary(iterator, os.Stdout)
-}
-
-func WriteBinaryBatch(iterator obiseq.IBioSequenceBatch, file io.Writer, options ...WithOption) (obiseq.IBioSequenceBatch, error) {
-	opt := MakeOptions(options)
-
-	buffsize := iterator.BufferSize()
-	newIter := obiseq.MakeIBioSequenceBatch(buffsize)
-
-	nwriters := opt.ParallelWorkers()
-
-	chunkchan := make(chan FileChunck)
-
-	newIter.Add(nwriters)
-
-	go func() {
-		newIter.Wait()
-		for len(chunkchan) > 0 {
-			time.Sleep(time.Millisecond)
-		}
-		close(chunkchan)
-		for len(newIter.Channel()) > 0 {
-			time.Sleep(time.Millisecond)
-		}
-		close(newIter.Channel())
-	}()
-
-	ff := func(iterator obiseq.IBioSequenceBatch) {
-		blob := make([]byte, 0, 10240)
-		for iterator.Next() {
-			batch := iterator.Get()
-			blobsize := batch.Slice().SizeHint()
-			if blobsize > cap(blob) {
-				blob = make([]byte, 0, blobsize*2+8)
-			}
-			_, _, err := surge.MarshalI64(int64(blobsize), blob, 8)
-			if err != nil {
-				log.Fatalf("error in reading binary file %v\n", err)
-			}
-			data := blob[8 : 8+blobsize]
-			_, _, err = batch.Slice().Marshal(data, blobsize)
-			if err != nil {
-				log.Fatalf("error in reading binary file %v\n", err)
-			}
-
-			chunkchan <- FileChunck{
-				data,
-				batch.Order(),
-			}
-			newIter.Channel() <- batch
-		}
-		newIter.Done()
-	}
-
-	log.Println("Start of the binary file writing")
-	go ff(iterator)
-	for i := 0; i < nwriters-1; i++ {
-		go ff(iterator.Split())
-	}
-
-	next_to_send := 0
-	received := make(map[int]FileChunck, 100)
-
-	go func() {
-		for chunk := range chunkchan {
-			if chunk.order == next_to_send {
-				file.Write(chunk.text)
-				next_to_send++
-				chunk, ok := received[next_to_send]
-				for ok {
-					file.Write(chunk.text)
-					delete(received, next_to_send)
-					next_to_send++
-					chunk, ok = received[next_to_send]
-				}
-			} else {
-				received[chunk.order] = chunk
-			}
-
-		}
-	}()
-
-	return newIter, nil
-}
-
-func WriteBinaryBatchToStdout(iterator obiseq.IBioSequenceBatch, options ...WithOption) (obiseq.IBioSequenceBatch, error) {
-	return WriteBinaryBatch(iterator, os.Stdout, options...)
-}
-
-func WriteBinaryBatchToFile(iterator obiseq.IBioSequenceBatch,
-	filename string,
-	options ...WithOption) (obiseq.IBioSequenceBatch, error) {
-
-	file, err := os.Create(filename)
-
-	if err != nil {
-		log.Fatalf("open file error: %v", err)
-		return obiseq.NilIBioSequenceBatch, err
-	}
-
-	return WriteBinaryBatch(iterator, file, options...)
-}
diff --git a/pkg/obiformats/fastseq_json_header.go b/pkg/obiformats/fastseq_json_header.go
index 5daba14..adc6c80 100644
--- a/pkg/obiformats/fastseq_json_header.go
+++ b/pkg/obiformats/fastseq_json_header.go
@@ -1,6 +1,7 @@
 package obiformats
 
 import (
+	"log"
 	"strings"
 
 	"git.metabarcoding.org/lecasofts/go/obitools/pkg/obiseq"
@@ -40,7 +41,11 @@ func _parse_json_header_(header string, annotations obiseq.Annotation) string {
 
 	stop++
 
-	json.Unmarshal([]byte(header)[start:stop], annotations)
+	err := json.Unmarshal([]byte(header)[start:stop], &annotations)
+	if err != nil {
+		log.Fatalf("annotation parsing error on %s : %v\n", header, err)
+	}
+
 	return strings.TrimSpace(header[stop:])
 }
 
diff --git a/pkg/obiformats/fastseq_read.go b/pkg/obiformats/fastseq_read.go
index 5cada79..12367ea 100644
--- a/pkg/obiformats/fastseq_read.go
+++ b/pkg/obiformats/fastseq_read.go
@@ -122,9 +122,10 @@ func ReadFastSeqBatchFromFile(filename string, options ...WithOption) (obiseq.IB
 
 	go _FastseqReader(pointer, newIter, opt.BatchSize())
 	parser := opt.ParseFastSeqHeader()
+
 	if parser != nil {
 		return IParseFastSeqHeaderBatch(newIter, options...), err
-	}
+	} 
 
 	return newIter, err
 }
diff --git a/pkg/obiseq/surge.go b/pkg/obiseq/surge.go
deleted file mode 100644
index b6d43fc..0000000
--- a/pkg/obiseq/surge.go
+++ /dev/null
@@ -1,105 +0,0 @@
-package obiseq
-
-import "github.com/renproject/surge"
-
-func (sequence BioSequence) SizeHint() int {
-	return surge.SizeHintString(sequence.sequence.id) +
-		surge.SizeHintString(sequence.sequence.definition) +
-		surge.SizeHintBytes(sequence.sequence.sequence) +
-		surge.SizeHintBytes(sequence.sequence.qualities) +
-		surge.SizeHintBytes(sequence.sequence.feature) +
-		surge.SizeHint(sequence.sequence.annotations)
-}
-
-func (sequence BioSequence) Marshal(buf []byte, rem int) ([]byte, int, error) {
-	var err error
-	if buf, rem, err = surge.MarshalString(sequence.sequence.id, buf, rem); err != nil {
-		return buf, rem, err
-	}
-	if buf, rem, err = surge.MarshalString(sequence.sequence.definition, buf, rem); err != nil {
-		return buf, rem, err
-	}
-	if buf, rem, err = surge.MarshalBytes(sequence.sequence.sequence, buf, rem); err != nil {
-		return buf, rem, err
-	}
-	if buf, rem, err = surge.MarshalBytes(sequence.sequence.qualities, buf, rem); err != nil {
-		return buf, rem, err
-	}
-	if buf, rem, err = surge.MarshalBytes(sequence.sequence.feature, buf, rem); err != nil {
-		return buf, rem, err
-	}
-	if buf, rem, err = surge.Marshal(sequence.sequence.annotations, buf, rem); err != nil {
-		return buf, rem, err
-	}
-
-	return buf, rem, err
-}
-
-// Unmarshal is the opposite of Marshal, and requires
-// a pointer receiver.
-func (sequence *BioSequence) Unmarshal(buf []byte, rem int) ([]byte, int, error) {
-	var err error
-	if buf, rem, err = surge.UnmarshalString(&(sequence.sequence.id), buf, rem); err != nil {
-		return buf, rem, err
-	}
-	if buf, rem, err = surge.UnmarshalString(&(sequence.sequence.definition), buf, rem); err != nil {
-		return buf, rem, err
-	}
-	if buf, rem, err = surge.UnmarshalBytes(&(sequence.sequence.sequence), buf, rem); err != nil {
-		return buf, rem, err
-	}
-	if buf, rem, err = surge.UnmarshalBytes(&(sequence.sequence.qualities), buf, rem); err != nil {
-		return buf, rem, err
-	}
-	if buf, rem, err = surge.UnmarshalBytes(&(sequence.sequence.feature), buf, rem); err != nil {
-		return buf, rem, err
-	}
-	if buf, rem, err = surge.Unmarshal(&(sequence.sequence.annotations), buf, rem); err != nil {
-		return buf, rem, err
-	}
-	return buf, rem, err
-}
-
-func (sequences BioSequenceSlice) SizeHint() int {
-	size := surge.SizeHintI64
-	for _, s := range sequences {
-		size += s.SizeHint()
-	}
-
-	return size
-}
-
-func (sequences BioSequenceSlice) Marshal(buf []byte, rem int) ([]byte, int, error) {
-	var err error
-
-	if buf, rem, err = surge.MarshalI64(int64(len(sequences)), buf, rem); err != nil {
-		return buf, rem, err
-	}
-
-	for _, s := range sequences {
-		if buf, rem, err = s.Marshal(buf, rem); err != nil {
-			return buf, rem, err
-		}
-	}
-
-	return buf, rem, err
-}
-
-func (sequences *BioSequenceSlice) Unmarshal(buf []byte, rem int) ([]byte, int, error) {
-	var err error
-	var length int64
-
-	if buf, rem, err = surge.UnmarshalI64(&length, buf, rem); err != nil {
-		return buf, rem, err
-	}
-
-	*sequences = make(BioSequenceSlice, length)
-
-	for i := 0; i < int(length); i++ {
-		if buf, rem, err = ((*sequences)[i]).Unmarshal(buf, rem); err != nil {
-			return buf, rem, err
-		}
-	}
-
-	return buf, rem, err
-}