diff --git a/package.json b/package.json
index fcddf972d..d9495df4b 100644
--- a/package.json
+++ b/package.json
@@ -62,7 +62,8 @@
 		"regenerator-runtime": "^0.13.3",
 		"reselect": "^4.0.0",
 		"swr": "^0.1.16",
-		"whatwg-fetch": "^3.0.0"
+		"whatwg-fetch": "^3.0.0",
+		"yaml": "^1.9.2"
 	},
 	"scripts": {
 		"prepare": "node source/scripts/prepare.js",
@@ -101,7 +102,7 @@
 		"mon-entreprise:serve": "PORT=5000 serve --config serve.mon-entreprise.json --no-clipboard",
 		"mon-entreprise:test": "cypress open --browser chromium",
 		"mycompanyinfrance:serve": "PORT=5001 serve --config serve.infrance.json --no-clipboard",
-		"mycompanyinfrance:test": "cypress open --browser chromium --env language=en --config baseUrl=http://localhost:8080/infrance",
+		"mycompanyinfrance:test": "cypress open --browser chromium --config baseUrl=http://localhost:8080/infrance",
 		"serve-dev": "yarn run mon-entreprise:serve & yarn run mycompanyinfrance:serve"
 	},
 	"devDependencies": {
diff --git a/source/components/Documentation/RuleSource.tsx b/source/components/Documentation/RuleSource.tsx
index 70d36d17c..a5ef6da7f 100644
--- a/source/components/Documentation/RuleSource.tsx
+++ b/source/components/Documentation/RuleSource.tsx
@@ -1,5 +1,5 @@
 import { ParsedRule } from 'Engine/types'
-import { safeDump } from 'js-yaml'
+import yaml from 'yaml'
 import React from 'react'
 import rules from 'Rules'
 import PublicodeHighlighter from '../ui/PublicodeHighlighter'
@@ -12,7 +12,7 @@ export default function RuleSource({ dottedName }: RuleSourceProps) {
 	return (
 		<section>
 			<h3>Source publicode</h3>
-			<PublicodeHighlighter source={safeDump({ [dottedName]: source })} />
+			<PublicodeHighlighter source={yaml.stringify({ [dottedName]: source })} />
 			<p className="ui__ notice">
 				Ci-dessus la règle d'origine, écrite en publicode. Publicode est un
 				langage déclaratif développé par beta.gouv.fr en partenariat avec
diff --git a/source/engine/parseRules.ts b/source/engine/parseRules.ts
index d63e8e055..83f1de2df 100644
--- a/source/engine/parseRules.ts
+++ b/source/engine/parseRules.ts
@@ -1,5 +1,5 @@
 import parseRule from 'Engine/parseRule'
-import { safeLoad } from 'js-yaml'
+import yaml from 'yaml'
 import { lensPath, set } from 'ramda'
 import { compilationError } from './error'
 import { parseReference } from './parseReference'
@@ -10,7 +10,7 @@ export default function parseRules<Names extends string>(
 ): ParsedRules<Names> {
 	const rules =
 		typeof rawRules === 'string'
-			? (safeLoad(rawRules.replace(/\t/g, '  ')) as Rules<Names>)
+			? (yaml.parse(rawRules.replace(/\t/g, '  ')) as Rules<Names>)
 			: { ...rawRules }
 
 	extractInlinedNames(rules)
diff --git a/source/scripts/i18n/translate-rules.js b/source/scripts/i18n/translate-rules.js
index 93bc437b0..9a56baace 100644
--- a/source/scripts/i18n/translate-rules.js
+++ b/source/scripts/i18n/translate-rules.js
@@ -1,4 +1,4 @@
-var { safeDump } = require('js-yaml')
+var { stringify } = require('yaml')
 var fs = require('fs')
 
 const {
@@ -9,7 +9,10 @@ const {
 
 const [missingTranslations, resolved] = getRulesMissingTranslations()
 
-fs.writeFileSync(rulesTranslationPath, safeDump(resolved, { sortKeys: true }))
+fs.writeFileSync(
+	rulesTranslationPath,
+	stringify(resolved, { sortMapEntries: true })
+)
 
 missingTranslations.forEach(async ([dottedName, attr, value]) => {
 	try {
@@ -18,7 +21,7 @@ missingTranslations.forEach(async ([dottedName, attr, value]) => {
 		// C'est très bourrin, mais on ne veut pas perdre une traduction qu'on a payé
 		fs.writeFileSync(
 			rulesTranslationPath,
-			safeDump(resolved, { sortKeys: true })
+			stringify(resolved, { sortMapEntries: true })
 		)
 	} catch (e) {
 		console.log(e)
diff --git a/source/scripts/i18n/translate-ui.js b/source/scripts/i18n/translate-ui.js
index 99393818d..c378bc132 100644
--- a/source/scripts/i18n/translate-ui.js
+++ b/source/scripts/i18n/translate-ui.js
@@ -1,4 +1,4 @@
-var { safeDump, safeLoad } = require('js-yaml')
+var { stringify, parse } = require('yaml')
 var R = require('ramda')
 var fs = require('fs')
 
@@ -9,7 +9,7 @@ const {
 } = require('./utils')
 
 const missingTranslations = getUiMissingTranslations()
-let translatedKeys = safeLoad(fs.readFileSync(UiTranslationPath, 'utf-8'))
+let translatedKeys = parse(fs.readFileSync(UiTranslationPath, 'utf-8'))
 
 Object.entries(missingTranslations)
 	.map(([key, value]) => [key, value === 'NO_TRANSLATION' ? key : value])
@@ -23,7 +23,7 @@ Object.entries(missingTranslations)
 			)
 			fs.writeFileSync(
 				UiTranslationPath,
-				safeDump(translatedKeys, { sortKeys: true })
+				stringify(translatedKeys, { sortMapEntries: true })
 			)
 		} catch (e) {
 			console.log(e)
diff --git a/source/scripts/i18n/utils.js b/source/scripts/i18n/utils.js
index 9e586b101..a2c1e3562 100644
--- a/source/scripts/i18n/utils.js
+++ b/source/scripts/i18n/utils.js
@@ -6,7 +6,7 @@ let R = require('ramda')
 var querystring = require('querystring')
 let { readRules } = require('../rules')
 
-let { safeLoad } = require('js-yaml')
+let { parse } = require('yaml')
 let rulesTranslationPath = path.resolve('source/locales/rules-en.yaml')
 let UiTranslationPath = path.resolve('source/locales/en.yaml')
 
@@ -23,7 +23,7 @@ let attributesToTranslate = [
 function getRulesMissingTranslations() {
 	let rules = readRules()
 
-	let currentExternalization = safeLoad(
+	let currentExternalization = parse(
 		fs.readFileSync(rulesTranslationPath, 'utf-8')
 	)
 
@@ -119,7 +119,7 @@ const getUiMissingTranslations = () => {
 	const staticKeys = require(path.resolve(
 		'source/locales/static-analysis-fr.json'
 	))
-	const translatedKeys = safeLoad(fs.readFileSync(UiTranslationPath, 'utf-8'))
+	const translatedKeys = parse(fs.readFileSync(UiTranslationPath, 'utf-8'))
 
 	const missingTranslations = Object.keys(staticKeys).filter(key => {
 		if (key.match(/^\{.*\}$/)) {
diff --git a/source/scripts/rules.js b/source/scripts/rules.js
index 15966d2e3..9101941c3 100644
--- a/source/scripts/rules.js
+++ b/source/scripts/rules.js
@@ -3,7 +3,7 @@
 
 const fs = require('fs')
 const path = require('path')
-const yaml = require('js-yaml')
+const yaml = require('yaml')
 
 const publicodesDir = path.resolve(__dirname, '../rules')
 
@@ -22,7 +22,7 @@ function concatenateFilesInDir(dirPath = publicodesDir) {
 }
 
 function readRules() {
-	return yaml.safeLoad(concatenateFilesInDir())
+	return yaml.parse(concatenateFilesInDir())
 }
 
 exports.readRules = readRules
diff --git a/source/sites/publi.codes/Studio.tsx b/source/sites/publi.codes/Studio.tsx
index eead76968..061af2e75 100644
--- a/source/sites/publi.codes/Studio.tsx
+++ b/source/sites/publi.codes/Studio.tsx
@@ -1,13 +1,12 @@
 // import { ControlledEditor } from '@monaco-editor/react'
 import Engine from 'Engine'
 import { formatValue } from 'Engine/format'
-import { safeLoad } from 'js-yaml'
+import yaml from 'yaml'
 import { last } from 'ramda'
 import React, { useCallback, useEffect, useMemo, useState } from 'react'
 import emoji from 'react-easy-emoji'
 import MonacoEditor from 'react-monaco-editor'
 import { useLocation } from 'react-router'
-import { DottedName } from 'Rules'
 import styled from 'styled-components'
 
 const EXAMPLE_CODE = `
@@ -58,7 +57,7 @@ export default function Studio() {
 
 	const targets = useMemo(() => {
 		try {
-			return Object.keys(safeLoad(debouncedEditorValue) ?? {})
+			return Object.keys(yaml.parse(debouncedEditorValue) ?? {})
 		} catch (e) {
 			console.error(e)
 			return []
diff --git a/yarn.lock b/yarn.lock
index ef3b1c441..5a33b7b19 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -12598,6 +12598,13 @@ yaml@^1.7.2:
   dependencies:
     "@babel/runtime" "^7.8.7"
 
+yaml@^1.9.2:
+  version "1.9.2"
+  resolved "https://registry.yarnpkg.com/yaml/-/yaml-1.9.2.tgz#f0cfa865f003ab707663e4f04b3956957ea564ed"
+  integrity sha512-HPT7cGGI0DuRcsO51qC1j9O16Dh1mZ2bnXwsi0jrSpsLz0WxOLSLXfkABVl6bZO629py3CU+OMJtpNHDLB97kg==
+  dependencies:
+    "@babel/runtime" "^7.9.2"
+
 yamljs@^0.3.0:
   version "0.3.0"
   resolved "https://registry.yarnpkg.com/yamljs/-/yamljs-0.3.0.tgz#dc060bf267447b39f7304e9b2bfbe8b5a7ddb03b"