diff --git a/packages/analytics/src/upload.js b/packages/analytics/src/upload.js
index 73f4f7e2..c3626056 100644
--- a/packages/analytics/src/upload.js
+++ b/packages/analytics/src/upload.js
@@ -1,6 +1,5 @@
 import { unlink } from 'fs';
 import debug from 'debug';
-import writeTo from 'stream-write';
 import tempy from 'tempy';
 
 /**
@@ -59,5 +58,5 @@ export default async function upload(data, feed) {
         const cbk = () => debug('ezs')('[upload] unlink file.', tmpfile);
         return setTimeout(() => unlink(tmpfile, cbk), cleanupDelay * 1000);
     }
-    return writeTo(this.input, data, () => feed.end());
+    return this.ezs.writeTo(this.input, data, () => feed.end());
 }
diff --git a/packages/istex/src/istex.js b/packages/istex/src/istex.js
index 08942c8f..420ee5ae 100644
--- a/packages/istex/src/istex.js
+++ b/packages/istex/src/istex.js
@@ -1,4 +1,3 @@
-import ezs from '@ezs/core';
 import { PassThrough } from 'stream';
 import os from 'os';
 import queue from 'async.queue';
@@ -12,7 +11,7 @@ const worker = (stream) => (data, done) => {
     writeTo(stream, data, () => done());
 };
 
-const getAndWriteQueries = (data, options, feed) => new Promise(
+const getAndWriteQueries = (ezs, data, options, feed) => new Promise(
     (resolve, reject) => {
         if (!Array.isArray(data)) {
             return reject(new Error('unexpected data. Should be an array.'));
@@ -43,7 +42,7 @@ const getAndWriteQueries = (data, options, feed) => new Promise(
     },
 );
 
-const getAndWriteIdentifiers = (data, options, feed) => new Promise(
+const getAndWriteIdentifiers = (ezs, data, options, feed) => new Promise(
     (resolve, reject) => {
         if (!Array.isArray(data)) {
             return reject(new Error('unexpected data. Should be an array.'));
@@ -115,8 +114,9 @@ async function ISTEX(data, feed) {
         field,
         sid,
     };
-    await getAndWriteQueries(queries, options, feed);
-    await getAndWriteIdentifiers(identifiers, options, feed);
+    const { ezs } = this;
+    await getAndWriteQueries(ezs, queries, options, feed);
+    await getAndWriteIdentifiers(ezs, identifiers, options, feed);
     feed.end();
 }
 
diff --git a/packages/transformers/src/operations/NUMBER.js b/packages/transformers/src/operations/NUMBER.js
index 1982ad14..bfbd803c 100644
--- a/packages/transformers/src/operations/NUMBER.js
+++ b/packages/transformers/src/operations/NUMBER.js
@@ -1,7 +1,8 @@
 import { transformer } from './transformer';
 
 export const valueToNumber = value => {
-    const number = Number(value);
+
+    const number = typeof value === 'number' ? value : Number(String(value).replace(/,/, '.'));
 
     return Number.isNaN(number) ? 0 : number;
 };
diff --git a/packages/transformers/src/operations/NUMBER.spec.js b/packages/transformers/src/operations/NUMBER.spec.js
index d79cbf85..de287c2f 100644
--- a/packages/transformers/src/operations/NUMBER.spec.js
+++ b/packages/transformers/src/operations/NUMBER.spec.js
@@ -13,6 +13,14 @@ describe('NUMBER', () => {
         expect(valueToNumber(1234)).toBe(1234);
     });
 
+    it('should return 12.34', () => {
+        expect(valueToNumber('12.34')).toBe(12.34);
+    });
+
+    it('should return 12,34', () => {
+        expect(valueToNumber('12,34')).toBe(12.34);
+    });
+
     it('should return 0 if value is null', () => {
         expect(valueToNumber(null)).toBe(0);
     });