diff --git a/src/RNASeq.nf b/src/RNASeq.nf
index 86afe6400616db4b6ec9be14ef2d1d9e83af907a..9dd795f46f39536b6b5a976b6e7b2328a9bb41b0 100644
--- a/src/RNASeq.nf
+++ b/src/RNASeq.nf
@@ -111,3 +111,79 @@ bedtools getfasta -name \
 """
 }
 
+/*
+* Kallisto :
+* Imputs : fastq files
+* Imputs : fasta files
+* Output : bam files
+*/
+
+/*                      fasta indexing                                     */
+params.fasta = "$baseDir/data/bam/*.fasta"
+
+log.info "fasta files : ${params.fasta}"
+
+Channel
+  .fromPath( params.fasta )
+  .ifEmpty { error "Cannot find any fasta files matching: ${params.fasta}" }
+  .set { fasta_file }
+
+process index_fasta {
+  tag "$fasta.baseName"
+  publishDir "results/mapping/index/", mode: 'copy'
+
+  input:
+    file fasta from fasta_file
+
+  output:
+    file "*.index*" into index_files
+
+  script:
+"""
+kallisto index -k 31 --make-unique -i ${fasta.baseName}.index ${fasta} \
+> ${fasta.baseName}_kallisto_report.txt
+"""
+}
+
+
+/*
+* for paired-end data
+*/
+
+params.fastq = "$baseDir/data/fastq/*_{1,2}.fastq"
+params.index = "$baseDir/data/index/*.index.*"
+
+log.info "fastq files : ${params.fastq}"
+log.info "index files : ${params.index}"
+
+Channel
+  .fromFilePairs( params.fastq )
+  .ifEmpty { error "Cannot find any fastq files matching: ${params.fastq}" }
+  .set { fastq_files }
+Channel
+  .fromPath( params.index )
+  .ifEmpty { error "Cannot find any index files matching: ${params.index}" }
+  .set { index_files }
+
+process mapping_fastq {
+  tag "$reads"
+  cpus 4
+  publishDir "results/mapping/quantification/", mode: 'copy'
+
+  input:
+  file reads from fastq_files
+  file index from index_files.toList()
+
+  output:
+  file "*" into counts_files
+
+  script:
+"""
+mkdir ${reads[0].baseName}
+kallisto quant -i ${index} -t ${task.cpus} \
+--bias --bootstrap-samples 100 -o ${reads[0].baseName} \
+${reads[0]} ${reads[1]} &> ${reads[0].baseName}_kallisto_report.txt
+"""
+}
+
+