--- a/.hgignore	Fri Jun 14 14:49:14 2019 +0200
+++ b/.hgignore	Fri Jun 14 15:30:33 2019 +0200
@@ -1,4 +1,5 @@
 # Application
+src/web/app/languages/*
 src/web/app/plugins/*
 src/web/app/mu-plugins/*/
 src/web/app/upgrade

--- a/src/composer.json	Fri Jun 14 14:49:14 2019 +0200
+++ b/src/composer.json	Fri Jun 14 15:30:33 2019 +0200
@@ -24,6 +24,10 @@
     {
       "type": "composer",
       "url": "https://wpackagist.org"
+    },
+    {
+      "type": "composer",
+      "url": "https://wp-languages.github.io"
     }
   ],
   "require": {
@@ -34,7 +38,8 @@
     "roots/wordpress": "5.2.1",
     "roots/wp-config": "1.0.0",
     "roots/wp-password-bcrypt": "1.0.0",
-    "wp-cli/wp-cli-bundle": "*"
+    "wp-cli/wp-cli-bundle": "*",
+    "koodimonni-language/core-fr_fr": "*"
   },
   "require-dev": {
     "squizlabs/php_codesniffer": "^3.0.2",
@@ -46,6 +51,9 @@
       "web/app/plugins/{$name}/": ["type:wordpress-plugin"],
       "web/app/themes/{$name}/": ["type:wordpress-theme"]
     },
+    "dropin-paths": {
+      "web/app/languages/": ["vendor:koodimonni-language"]
+    },
     "wordpress-install-dir": "web/wp"
   },
   "scripts": {

--- a/src/composer.lock	Fri Jun 14 14:49:14 2019 +0200
+++ b/src/composer.lock	Fri Jun 14 15:30:33 2019 +0200
@@ -4,7 +4,7 @@
         "Read more about it at https://getcomposer.org/doc/01-basic-usage.md#installing-dependencies",
         "This file is @generated automatically"
     ],
-    "content-hash": "5f2f8a725f3371d5a52344a08bfbd6ac",
+    "content-hash": "f2877db893f6e5be9d1af1a33b7e7f10",
     "packages": [
         {
             "name": "composer/ca-bundle",
@@ -618,6 +618,68 @@
             "time": "2019-01-14T23:55:14+00:00"
         },
         {
+            "name": "koodimonni-language/core-fr_fr",
+            "version": "5.2.1",
+            "dist": {
+                "type": "zip",
+                "url": "https://downloads.wordpress.org/translation/core/5.2.1/fr_FR.zip"
+            },
+            "require": {
+                "koodimonni/composer-dropin-installer": ">=0.2.3"
+            },
+            "type": "wordpress-language",
+            "description": "Wordpress core translation for French (France) - fr_fr",
+            "keywords": [
+                "Translation",
+                "Wordpress",
+                "core",
+                "fr_fr"
+            ]
+        },
+        {
+            "name": "koodimonni/composer-dropin-installer",
+            "version": "1.2",
+            "source": {
+                "type": "git",
+                "url": "https://github.com/Koodimonni/Composer-Dropin-Installer.git",
+                "reference": "a749f19e3a3bc05529190961ed7529592b20138e"
+            },
+            "dist": {
+                "type": "zip",
+                "url": "https://api.github.com/repos/Koodimonni/Composer-Dropin-Installer/zipball/a749f19e3a3bc05529190961ed7529592b20138e",
+                "reference": "a749f19e3a3bc05529190961ed7529592b20138e",
+                "shasum": ""
+            },
+            "require": {
+                "composer-plugin-api": "^1.0"
+            },
+            "require-dev": {
+                "phpunit/phpunit": "3.7.*-dev"
+            },
+            "type": "composer-plugin",
+            "extra": {
+                "class": "Koodimonni\\Composer\\Dropin"
+            },
+            "autoload": {
+                "psr-4": {
+                    "Koodimonni\\Composer\\": "src"
+                }
+            },
+            "notification-url": "https://packagist.org/downloads/",
+            "license": [
+                "WTFPL"
+            ],
+            "authors": [
+                {
+                    "name": "Onni Hakala",
+                    "email": "onni@koodimonni.fi",
+                    "role": "Developer"
+                }
+            ],
+            "description": "Install packages or a few files from packages into custom paths without overwriting existing stuff.",
+            "time": "2018-02-04T10:52:01+00:00"
+        },
+        {
             "name": "mck89/peast",
             "version": "v1.9.2",
             "source": {