diff --git a/cmd/obitools/obiuniq/main.go b/cmd/obitools/obiuniq/main.go
index 959cf91..cba8b73 100644
--- a/cmd/obitools/obiuniq/main.go
+++ b/cmd/obitools/obiuniq/main.go
@@ -30,6 +30,7 @@ func main() {
 	// trace.Start(ftrace)
 	// defer trace.Stop()
 
+	obioptions.SetReadQualities(false)
 	optionParser := obioptions.GenerateOptionParser(obiuniq.OptionSet)
 
 	_, args := optionParser(os.Args)
diff --git a/pkg/obichunk/chunk_on_disk.go b/pkg/obichunk/chunk_on_disk.go
index bd85a1a..4347180 100644
--- a/pkg/obichunk/chunk_on_disk.go
+++ b/pkg/obichunk/chunk_on_disk.go
@@ -12,6 +12,13 @@ import (
 	"git.metabarcoding.org/obitools/obitools4/obitools4/pkg/obiseq"
 )
 
+// tempDir creates a temporary directory with a prefix "obiseq_chunks_"
+// in the system's temporary directory. It returns the path of the
+// created directory and any error encountered during the creation process.
+//
+// If the directory creation is successful, the path to the new
+// temporary directory is returned. If there is an error, it returns
+// an empty string and the error encountered.
 func tempDir() (string, error) {
 	dir, err := os.MkdirTemp(os.TempDir(), "obiseq_chunks_")
 	if err != nil {
@@ -20,6 +27,19 @@ func tempDir() (string, error) {
 	return dir, nil
 }
 
+// find searches for files with a specific extension in the given root directory
+// and its subdirectories. It returns a slice of strings containing the paths
+// of the found files.
+//
+// Parameters:
+// - root: The root directory to start the search from.
+// - ext: The file extension to look for (including the leading dot, e.g., ".txt").
+//
+// Returns:
+// A slice of strings containing the paths of files that match the specified
+// extension. If no files are found, an empty slice is returned. Any errors
+// encountered during the directory traversal will be returned as part of the
+// WalkDir function's error handling.
 func find(root, ext string) []string {
 	var a []string
 	filepath.WalkDir(root, func(s string, d fs.DirEntry, e error) error {
@@ -34,6 +54,24 @@ func find(root, ext string) []string {
 	return a
 }
 
+// ISequenceChunkOnDisk processes a sequence iterator by distributing the sequences
+// into chunks stored on disk. It uses a classifier to determine how to distribute
+// the sequences and returns a new iterator for the processed sequences.
+//
+// Parameters:
+//   - iterator: An iterator of biosequences to be processed.
+//   - classifier: A pointer to a BioSequenceClassifier used to classify the sequences
+//     during distribution.
+//
+// Returns:
+// An iterator of biosequences representing the processed chunks. If an error occurs
+// during the creation of the temporary directory or any other operation, it returns
+// an error along with a nil iterator.
+//
+// The function operates asynchronously, creating a temporary directory to store
+// the sequence chunks. Once the processing is complete, the temporary directory
+// is removed. The function logs the number of batches created and the processing
+// status of each batch.
 func ISequenceChunkOnDisk(iterator obiiter.IBioSequence,
 	classifier *obiseq.BioSequenceClassifier) (obiiter.IBioSequence, error) {
 	dir, err := tempDir()
diff --git a/pkg/obiformats/dispatcher.go b/pkg/obiformats/dispatcher.go
index 0aedf8a..544bace 100644
--- a/pkg/obiformats/dispatcher.go
+++ b/pkg/obiformats/dispatcher.go
@@ -14,10 +14,40 @@ import (
 	"git.metabarcoding.org/obitools/obitools4/obitools4/pkg/obiiter"
 )
 
+// SequenceBatchWriterToFile is a function type that defines a method for writing
+// a batch of biosequences to a specified file. It takes an iterator of biosequences,
+// a filename, and optional configuration options, and returns an iterator of biosequences
+// along with any error encountered during the writing process.
+//
+// Parameters:
+// - iterator: An iterator of biosequences to be written to the file.
+// - filename: The name of the file where the sequences will be written.
+// - options: Optional configuration options for the writing process.
+//
+// Returns:
+// An iterator of biosequences that may have been modified during the writing process
+// and an error if the writing operation fails.
 type SequenceBatchWriterToFile func(iterator obiiter.IBioSequence,
 	filename string,
 	options ...WithOption) (obiiter.IBioSequence, error)
 
+// WriterDispatcher manages the writing of data to files based on a given
+// prototype name and a dispatcher for distributing the sequences. It
+// processes incoming data from the dispatcher in separate goroutines,
+// formatting and writing the data to files as specified.
+//
+// Parameters:
+//   - prototypename: A string that serves as a template for naming the output files.
+//   - dispatcher: An instance of IDistribute that provides the data to be written
+//     and manages the distribution of sequences.
+//   - formater: A function of type SequenceBatchWriterToFile that formats and writes
+//     the sequences to the specified file.
+//   - options: Optional configuration options for the writing process.
+//
+// The function operates asynchronously, launching goroutines for each new data
+// channel received from the dispatcher. It ensures that directories are created
+// as needed and handles errors during the writing process. The function blocks
+// until all writing jobs are completed.
 func WriterDispatcher(prototypename string,
 	dispatcher obiiter.IDistribute,
 	formater SequenceBatchWriterToFile,
@@ -34,7 +64,7 @@ func WriterDispatcher(prototypename string,
 				data, err := dispatcher.Outputs(newflux)
 
 				if err != nil {
-					log.Fatalf("Cannot retreive the new chanel : %v", err)
+					log.Fatalf("Cannot retrieve the new channel: %v", err)
 				}
 
 				key := dispatcher.Classifier().Value(newflux)
@@ -58,7 +88,7 @@ func WriterDispatcher(prototypename string,
 					info, err := os.Stat(directory)
 					switch {
 					case !os.IsNotExist(err) && !info.IsDir():
-						log.Fatalf("Cannot Create the directory %s", directory)
+						log.Fatalf("Cannot create the directory %s", directory)
 					case os.IsNotExist(err):
 						os.Mkdir(directory, 0755)
 					}
@@ -71,7 +101,7 @@ func WriterDispatcher(prototypename string,
 					options...)
 
 				if err != nil {
-					log.Fatalf("cannot open the output file for key %s",
+					log.Fatalf("Cannot open the output file for key %s",
 						dispatcher.Classifier().Value(newflux))
 				}
 
diff --git a/pkg/obiformats/fastqseq_read.go b/pkg/obiformats/fastqseq_read.go
index fe11869..f0716d3 100644
--- a/pkg/obiformats/fastqseq_read.go
+++ b/pkg/obiformats/fastqseq_read.go
@@ -131,7 +131,7 @@ func _storeSequenceQuality(bytes *bytes.Buffer, out *obiseq.BioSequence, quality
 	out.SetQualities(q)
 }
 
-func FastqChunkParser(quality_shift byte) func(string, io.Reader) (obiseq.BioSequenceSlice, error) {
+func FastqChunkParser(quality_shift byte, with_quality bool) func(string, io.Reader) (obiseq.BioSequenceSlice, error) {
 	parser := func(source string, input io.Reader) (obiseq.BioSequenceSlice, error) {
 
 		var identifier string
@@ -263,7 +263,9 @@ func FastqChunkParser(quality_shift byte) func(string, io.Reader) (obiseq.BioSeq
 				}
 			case 10:
 				if is_end_of_line {
-					_storeSequenceQuality(&qualBytes, sequences[len(sequences)-1], quality_shift)
+					if with_quality {
+						_storeSequenceQuality(&qualBytes, sequences[len(sequences)-1], quality_shift)
+					}
 					state = 11
 				} else {
 					qualBytes.WriteByte(C)
@@ -299,9 +301,10 @@ func _ParseFastqFile(
 	input ChannelSeqFileChunk,
 	out obiiter.IBioSequence,
 	quality_shift byte,
+	with_quality bool,
 ) {
 
-	parser := FastqChunkParser(quality_shift)
+	parser := FastqChunkParser(quality_shift, with_quality)
 
 	for chunks := range input {
 		sequences, err := parser(chunks.Source, chunks.Raw)
@@ -339,6 +342,7 @@ func ReadFastq(reader io.Reader, options ...WithOption) (obiiter.IBioSequence, e
 			chkchan,
 			out,
 			byte(obioptions.InputQualityShift()),
+			opt.ReadQualities(),
 		)
 	}
 
diff --git a/pkg/obiformats/options.go b/pkg/obiformats/options.go
index 0d14d2c..f478b2f 100644
--- a/pkg/obiformats/options.go
+++ b/pkg/obiformats/options.go
@@ -20,6 +20,7 @@ type __options__ struct {
 	appendfile            bool
 	compressed            bool
 	skip_empty            bool
+	with_quality          bool
 	csv_id                bool
 	csv_sequence          bool
 	csv_quality           bool
@@ -57,6 +58,7 @@ func MakeOptions(setters []WithOption) Options {
 		appendfile:            false,
 		compressed:            false,
 		skip_empty:            false,
+		with_quality:          true,
 		csv_id:                true,
 		csv_definition:        false,
 		csv_count:             false,
@@ -133,6 +135,10 @@ func (opt Options) SkipEmptySequence() bool {
 	return opt.pointer.skip_empty
 }
 
+func (opt Options) ReadQualities() bool {
+	return opt.pointer.with_quality
+}
+
 func (opt Options) CSVId() bool {
 	return opt.pointer.csv_id
 }
@@ -241,6 +247,14 @@ func OptionsSkipEmptySequence(skip bool) WithOption {
 	return f
 }
 
+func OptionsReadQualities(read bool) WithOption {
+	f := WithOption(func(opt Options) {
+		opt.pointer.with_quality = read
+	})
+
+	return f
+}
+
 func OptionsNewFile() WithOption {
 	f := WithOption(func(opt Options) {
 		opt.pointer.appendfile = false
diff --git a/pkg/obiiter/distribute.go b/pkg/obiiter/distribute.go
index ee2b080..9015b90 100644
--- a/pkg/obiiter/distribute.go
+++ b/pkg/obiiter/distribute.go
@@ -4,9 +4,25 @@ import (
 	"fmt"
 	"sync"
 
+	"git.metabarcoding.org/obitools/obitools4/obitools4/pkg/obioptions"
 	"git.metabarcoding.org/obitools/obitools4/obitools4/pkg/obiseq"
 )
 
+// IDistribute represents a distribution mechanism for biosequences.
+// It manages the outputs of biosequences, provides a channel for
+// new data notifications, and maintains a classifier for sequence
+// classification. It is designed to facilitate the distribution
+// of biosequences to various processing components.
+//
+// Fields:
+//   - outputs: A map that associates integer keys with corresponding
+//     biosequence outputs (IBioSequence).
+//   - news: A channel that sends notifications of new data available
+//     for processing, represented by integer identifiers.
+//   - classifier: A pointer to a BioSequenceClassifier used to classify
+//     the biosequences during distribution.
+//   - lock: A mutex for synchronizing access to the outputs and other
+//     shared resources to ensure thread safety.
 type IDistribute struct {
 	outputs    map[int]IBioSequence
 	news       chan int
@@ -26,16 +42,39 @@ func (dist *IDistribute) Outputs(key int) (IBioSequence, error) {
 	return iter, nil
 }
 
+// News returns a channel that provides notifications of new data
+// available for processing. The channel sends integer identifiers
+// representing the new data.
 func (dist *IDistribute) News() chan int {
 	return dist.news
 }
 
+// Classifier returns a pointer to the BioSequenceClassifier
+// associated with the distribution mechanism. This classifier
+// is used to classify biosequences during the distribution process.
 func (dist *IDistribute) Classifier() *obiseq.BioSequenceClassifier {
 	return dist.classifier
 }
 
+// Distribute organizes the biosequences from the iterator into batches
+// based on the provided classifier and batch sizes. It returns an
+// IDistribute instance that manages the distribution of the sequences.
+//
+// Parameters:
+//   - class: A pointer to a BioSequenceClassifier used to classify
+//     the biosequences during distribution.
+//   - sizes: Optional integer values specifying the batch size. If
+//     no sizes are provided, a default batch size of 5000 is used.
+//
+// Returns:
+// An IDistribute instance that contains the outputs of the
+// classified biosequences, a channel for new data notifications,
+// and the classifier used for distribution. The method operates
+// asynchronously, processing the sequences in separate goroutines.
+// It ensures that the outputs are closed and cleaned up once
+// processing is complete.
 func (iterator IBioSequence) Distribute(class *obiseq.BioSequenceClassifier, sizes ...int) IDistribute {
-	batchsize := 5000
+	batchsize := obioptions.CLIBatchSize()
 
 	outputs := make(map[int]IBioSequence, 100)
 	slices := make(map[int]*obiseq.BioSequenceSlice, 100)
diff --git a/pkg/obioptions/options.go b/pkg/obioptions/options.go
index e8b45e8..310d65c 100644
--- a/pkg/obioptions/options.go
+++ b/pkg/obioptions/options.go
@@ -27,6 +27,7 @@ var _PprofMudex = 10
 var _PprofGoroutine = 6060
 var _Quality_Shift_Input = byte(33)
 var _Quality_Shift_Output = byte(33)
+var _Read_Qualities = true
 
 type ArgumentParser func([]string) (*getoptions.GetOpt, []string)
 
@@ -259,6 +260,10 @@ func CLIBatchSize() int {
 	return _BatchSize
 }
 
+func CLIReadQualities() bool {
+	return _Read_Qualities
+}
+
 // SetDebugOn sets the debug mode on.
 func SetDebugOn() {
 	_Debug = true
@@ -269,6 +274,10 @@ func SetDebugOff() {
 	_Debug = false
 }
 
+func SetReadQualities(status bool) {
+	_Read_Qualities = status
+}
+
 // SetWorkerPerCore sets the number of workers per CPU core.
 //
 // It takes a float64 parameter representing the number of workers
diff --git a/pkg/obioptions/version.go b/pkg/obioptions/version.go
index c904d8d..e800a5d 100644
--- a/pkg/obioptions/version.go
+++ b/pkg/obioptions/version.go
@@ -7,7 +7,7 @@ import (
 // TODO: The version number is extracted from git. This induces that the version
 // corresponds to the last commit, and not the one when the file will be
 // commited
-var _Commit = "7884a74"
+var _Commit = "d29a56d"
 var _Version = "Release 4.3.0"
 
 // Version returns the version of the obitools package.
diff --git a/pkg/obitools/obiconvert/sequence_reader.go b/pkg/obitools/obiconvert/sequence_reader.go
index 83b22fe..9c1eaa7 100644
--- a/pkg/obitools/obiconvert/sequence_reader.go
+++ b/pkg/obitools/obiconvert/sequence_reader.go
@@ -99,6 +99,8 @@ func CLIReadBioSequences(filenames ...string) (obiiter.IBioSequence, error) {
 		opts = append(opts, obiformats.OptionsFastSeqHeaderParser(obiformats.ParseGuessedFastSeqHeader))
 	}
 
+	opts = append(opts, obiformats.OptionsReadQualities(obioptions.CLIReadQualities()))
+
 	nworkers := obioptions.CLIReadParallelWorkers()
 	if nworkers < 2 {
 		nworkers = 2