diff --git a/README.md b/README.md
index cfee912..a82ecd2 100644
--- a/README.md
+++ b/README.md
@@ -174,4 +174,7 @@ imagery database is licensed under [CC-BY-SA](https://creativecommons.org/licens
 Copyright (c) 2016 Eduard <edward17>; [MIT License](https://github.com/Edward17/LayersCollection/blob/gh-pages/LICENSE.md)
 * [Leaflet-providers](https://github.com/leaflet-extras/leaflet-providers)  
 Copyright (c) 2013 Leaflet Providers contributors All rights reserved.; [2-clause BSD License](https://github.com/leaflet-extras/leaflet-providers/blob/master/license.md)
-
+* [Fetch polyfill](https://github.com/Github/fetch)  
+Copyright (c) 2014-2016 GitHub, Inc.; [MIT License](https://github.com/github/fetch/blob/master/LICENSE)
+* [Promise Polyfill](https://github.com/taylorhakes/promise-polyfill)  
+Copyright (c) 2014 Taylor Hakes, Copyright (c) 2014 Forbes Lindesay; [MIT License](https://github.com/taylorhakes/promise-polyfill/blob/master/LICENSE)
diff --git a/package.json b/package.json
index a5dc449..c9f0cf8 100644
--- a/package.json
+++ b/package.json
@@ -48,9 +48,11 @@
     "leaflet.snogylop": "^0.4.0",
     "leaflet.stravasegments": "2.3.2",
     "mapbbcode": "MapBBCode/mapbbcode#v1.2.0",
+    "promise-polyfill": "^8.1.0",
     "seiyria-bootstrap-slider": "seiyria/bootstrap-slider#^9.8.1",
     "tether": "1.4.5",
-    "url-search-params": "~0.5.0"
+    "url-search-params": "~0.5.0",
+    "whatwg-fetch": "^3.0.0"
   },
   "devDependencies": {
     "autoprefixer": "^8.1.0",
@@ -211,6 +213,11 @@
         "dist/themes/default/style.css",
         "dist/themes/default/*.png"
       ]
+    },
+    "promise-polyfill": {
+      "main": [
+        "dist/polyfill.js"
+      ]
     }
   }
 }
diff --git a/yarn.lock b/yarn.lock
index 635c11b..0a5455d 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -4325,6 +4325,11 @@ progress-stream@^1.0.1:
     speedometer "~0.1.2"
     through2 "~0.2.3"
 
+promise-polyfill@^8.1.0:
+  version "8.1.0"
+  resolved "https://registry.yarnpkg.com/promise-polyfill/-/promise-polyfill-8.1.0.tgz#30059da54d1358ce905ac581f287e184aedf995d"
+  integrity sha512-OzSf6gcCUQ01byV4BgwyUCswlaQQ6gzXc23aLQWhicvfX9kfsUiUhgt3CCQej8jDnl8/PhGF31JdHX2/MzF3WA==
+
 psl@^1.1.24:
   version "1.1.31"
   resolved "https://registry.yarnpkg.com/psl/-/psl-1.1.31.tgz#e9aa86d0101b5b105cbe93ac6b784cd547276184"
@@ -5453,6 +5458,11 @@ vinyl@^2.0.0, vinyl@^2.0.1, vinyl@^2.1.0, vinyl@^2.2.0:
     remove-trailing-separator "^1.0.1"
     replace-ext "^1.0.0"
 
+whatwg-fetch@^3.0.0:
+  version "3.0.0"
+  resolved "https://registry.yarnpkg.com/whatwg-fetch/-/whatwg-fetch-3.0.0.tgz#fc804e458cc460009b1a2b966bc8817d2578aefb"
+  integrity sha512-9GSJUgz1D4MfyKU7KRqwOjXCXTqWdFNvEr7eUBYchQiVc744mqK/MzXPNR2WsPkmkOa4ywfg8C2n8h+13Bey1Q==
+
 which@^1.2.14:
   version "1.3.1"
   resolved "https://registry.yarnpkg.com/which/-/which-1.3.1.tgz#a45043d54f5805316da8d62f9f50918d3da70b0a"