diff --git a/src/app/js/formats/vega-lite/component/bar-chart/BarChartView.js b/src/app/js/formats/vega-lite/component/bar-chart/BarChartView.js
index dde456d5a..fd29597d5 100644
--- a/src/app/js/formats/vega-lite/component/bar-chart/BarChartView.js
+++ b/src/app/js/formats/vega-lite/component/bar-chart/BarChartView.js
@@ -16,7 +16,6 @@ import {
 } from '../../../chartsUtils';
 import BarChart from '../../models/BarChart';
 import { CustomActionVegaLite } from '../vega-lite-component';
-import deepClone from 'lodash.clonedeep';
 import InvalidFormat from '../../../InvalidFormat';
 import { VEGA_ACTIONS_WIDTH } from '../vega-lite-component/VegaLiteComponent';
 
@@ -33,7 +32,7 @@ class BarChartView extends Component {
 
         // Create a new bar chart instance
 
-        const barChartSpec = deepClone(new BarChart());
+        const barChartSpec = new BarChart();
 
         // Set all bar chart parameter the chosen by the administrator
 
diff --git a/src/app/js/formats/vega-lite/component/bubble-plot/BubblePlotView.js b/src/app/js/formats/vega-lite/component/bubble-plot/BubblePlotView.js
index 32921975e..648b68883 100644
--- a/src/app/js/formats/vega-lite/component/bubble-plot/BubblePlotView.js
+++ b/src/app/js/formats/vega-lite/component/bubble-plot/BubblePlotView.js
@@ -6,7 +6,6 @@ import compose from 'recompose/compose';
 import { field as fieldPropTypes } from '../../../../propTypes';
 import PropTypes from 'prop-types';
 import ContainerDimensions from 'react-container-dimensions';
-import deepClone from 'lodash.clonedeep';
 import {
     lodexOrderToIdOrder,
     VEGA_LITE_DATA_INJECT_TYPE_A,
@@ -25,7 +24,7 @@ class BubblePlotView extends Component {
 
         // Create a new bubble plot instance
 
-        const bubblePlot = deepClone(new BubblePlot());
+        const bubblePlot = new BubblePlot();
 
         // Set all bubble plot parameter the chosen by the administrator
 
diff --git a/src/app/js/formats/vega-lite/component/cartography/CartographyView.js b/src/app/js/formats/vega-lite/component/cartography/CartographyView.js
index 56b9597ef..9148294ef 100644
--- a/src/app/js/formats/vega-lite/component/cartography/CartographyView.js
+++ b/src/app/js/formats/vega-lite/component/cartography/CartographyView.js
@@ -2,7 +2,6 @@ import React, { Component } from 'react';
 import { connect } from 'react-redux';
 import PropTypes from 'prop-types';
 import compose from 'recompose/compose';
-import deepClone from 'lodash.clonedeep';
 import ContainerDimensions from 'react-container-dimensions';
 import { CustomActionVegaLite } from '../vega-lite-component';
 import {
@@ -27,7 +26,7 @@ class CartographyView extends Component {
 
         // Create a new cartography instance
 
-        const cartography = deepClone(new Cartography());
+        const cartography = new Cartography();
 
         // Set all cartography parameter the chosen by the administrator
 
diff --git a/src/app/js/formats/vega-lite/component/heatmap/HeatMapView.js b/src/app/js/formats/vega-lite/component/heatmap/HeatMapView.js
index 945a64521..56b2d7de9 100644
--- a/src/app/js/formats/vega-lite/component/heatmap/HeatMapView.js
+++ b/src/app/js/formats/vega-lite/component/heatmap/HeatMapView.js
@@ -7,7 +7,6 @@ import HeatMap from '../../models/HeatMap';
 import { field as fieldPropTypes } from '../../../../propTypes';
 import PropTypes from 'prop-types';
 import ContainerDimensions from 'react-container-dimensions';
-import deepClone from 'lodash.clonedeep';
 import {
     lodexOrderToIdOrder,
     VEGA_LITE_DATA_INJECT_TYPE_A,
@@ -25,7 +24,7 @@ class HeatMapView extends Component {
 
         // Create a new heat map instance
 
-        const heatMap = deepClone(new HeatMap());
+        const heatMap = new HeatMap();
 
         // Set all heat map parameter the chosen by the administrator
 
diff --git a/src/app/js/formats/vega-lite/component/pie-chart/PieChartView.js b/src/app/js/formats/vega-lite/component/pie-chart/PieChartView.js
index e61edd99f..af3878ee2 100644
--- a/src/app/js/formats/vega-lite/component/pie-chart/PieChartView.js
+++ b/src/app/js/formats/vega-lite/component/pie-chart/PieChartView.js
@@ -8,7 +8,6 @@ import ContainerDimensions from 'react-container-dimensions';
 import PieChart from '../../models/PieChart';
 import { CustomActionVegaLite } from '../vega-lite-component';
 import { VEGA_LITE_DATA_INJECT_TYPE_A } from '../../../chartsUtils';
-import deepClone from 'lodash.clonedeep';
 
 const styles = {
     container: {
@@ -22,7 +21,7 @@ class PieChartView extends Component {
 
         // Create a new pie chart instance
 
-        const pieChart = deepClone(new PieChart());
+        const pieChart = new PieChart();
 
         // enable the orderBy in vega-lite
 
diff --git a/src/app/js/formats/vega-lite/models/BarChart.js b/src/app/js/formats/vega-lite/models/BarChart.js
index 3351096e7..139b3ffd7 100644
--- a/src/app/js/formats/vega-lite/models/BarChart.js
+++ b/src/app/js/formats/vega-lite/models/BarChart.js
@@ -14,9 +14,12 @@ import {
 } from '../../chartsUtils';
 import { VEGA_ACTIONS_WIDTH } from '../component/vega-lite-component/VegaLiteComponent';
 import BasicChart from './BasicChart';
+import barChartVL from './json/bar_chart.vl.json';
+import barChartLabelsVL from './json/bar_chart_labels.vl.json';
+import deepClone from 'lodash.clonedeep';
 
 /**
- * Class use for create bar chart spec
+ * Class used to create bar chart spec
  */
 class BarChart extends BasicChart {
     /**
@@ -30,8 +33,8 @@ class BarChart extends BasicChart {
             top: 10,
             bottom: 0,
         };
-        this.model = require('./json/bar_chart.vl.json');
-        this.labelsModel = require('./json/bar_chart_labels.vl.json');
+        this.model = deepClone(barChartVL);
+        this.labelsModel = deepClone(barChartLabelsVL);
         this.scale = 'linear';
         this.labelAngle = {
             x: 0,
diff --git a/src/app/js/formats/vega-lite/models/BubblePlot.js b/src/app/js/formats/vega-lite/models/BubblePlot.js
index 2400e9beb..05c779d0a 100644
--- a/src/app/js/formats/vega-lite/models/BubblePlot.js
+++ b/src/app/js/formats/vega-lite/models/BubblePlot.js
@@ -1,9 +1,11 @@
 import HeatMap from './HeatMap';
+import bubblePlotVL from './json/bubble_plot.vl.json';
+import deepClone from 'lodash.clonedeep';
 
 class BubblePlot extends HeatMap {
     constructor() {
         super();
-        this.model = require('./json/bubble_plot.vl.json');
+        this.model = deepClone(bubblePlotVL);
     }
 
     /**
diff --git a/src/app/js/formats/vega-lite/models/Cartography.js b/src/app/js/formats/vega-lite/models/Cartography.js
index cb31b28e8..df5100fc8 100644
--- a/src/app/js/formats/vega-lite/models/Cartography.js
+++ b/src/app/js/formats/vega-lite/models/Cartography.js
@@ -1,9 +1,11 @@
 import BasicChart from './BasicChart';
 import { MAP_EUROPE, MAP_FRANCE, MAP_WORLD } from '../../chartsUtils';
 import { VEGA_ACTIONS_WIDTH } from '../component/vega-lite-component/VegaLiteComponent';
+import cartographyVL from './json/cartography.vl.json';
+import deepClone from 'lodash.clonedeep';
 
 /**
- * Class use for create cartography spec
+ * Class used to create cartography spec
  */
 class Cartography extends BasicChart {
     /**
@@ -11,7 +13,7 @@ class Cartography extends BasicChart {
      */
     constructor() {
         super();
-        this.model = require('./json/cartography.vl.json');
+        this.model = deepClone(cartographyVL);
         this.tooltip.category.field = 'properties.name';
         this.worldPosition = 'world';
         this.autosize = {
diff --git a/src/app/js/formats/vega-lite/models/HeatMap.js b/src/app/js/formats/vega-lite/models/HeatMap.js
index 5a204fe30..0382b4ea3 100644
--- a/src/app/js/formats/vega-lite/models/HeatMap.js
+++ b/src/app/js/formats/vega-lite/models/HeatMap.js
@@ -1,8 +1,10 @@
 import BasicChart from './BasicChart';
 import { LABEL_ASC, LABEL_DESC } from '../../chartsUtils';
+import heatmapVL from './json/heatmap.vl.json';
+import deepClone from 'lodash.clonedeep';
 
 /**
- * Class use for create heatmap spec
+ * Class used to create heatmap spec
  */
 class HeatMap extends BasicChart {
     /**
@@ -10,7 +12,7 @@ class HeatMap extends BasicChart {
      */
     constructor() {
         super();
-        this.model = require('./json/heatmap.vl.json');
+        this.model = deepClone(heatmapVL);
         this.flip = false;
         this.padding = {
             left: 10,
diff --git a/src/app/js/formats/vega-lite/models/PieChart.js b/src/app/js/formats/vega-lite/models/PieChart.js
index c2fc54e3d..5d4f2a888 100644
--- a/src/app/js/formats/vega-lite/models/PieChart.js
+++ b/src/app/js/formats/vega-lite/models/PieChart.js
@@ -1,7 +1,10 @@
 import BasicChart from './BasicChart';
+import pieChartVL from './json/pie_chart.vl.json';
+import pieChartLabelsVL from './json/pie_chart_labels.vl.json';
+import deepClone from 'lodash.clonedeep';
 
 /**
- * Class use for create pie chart spec
+ * Class used to create pie chart spec
  */
 class PieChart extends BasicChart {
     /**
@@ -9,8 +12,8 @@ class PieChart extends BasicChart {
      */
     constructor() {
         super();
-        this.model = require('./json/pie_chart.vl.json');
-        this.modelLabels = require('./json/pie_chart_labels.vl.json');
+        this.model = deepClone(pieChartVL);
+        this.modelLabels = deepClone(pieChartLabelsVL);
         this.labels = false;
     }