diff --git a/package-lock.json b/package-lock.json
index 18d340c..eadc699 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -386,19 +386,9 @@
       "dev": true
     },
     "async": {
-      "version": "2.6.0",
-      "resolved": "https://registry.npmjs.org/async/-/async-2.6.0.tgz",
-      "integrity": "sha512-xAfGg1/NTLBBKlHFmnd7PlmUW9KhVQIUuSrYem9xzFUZy13ScvtyGGejaae9iAVRiRq9+Cx7DPFaAAhCpyxyPw==",
-      "requires": {
-        "lodash": "^4.14.0"
-      },
-      "dependencies": {
-        "lodash": {
-          "version": "4.17.4",
-          "resolved": "https://registry.npmjs.org/lodash/-/lodash-4.17.4.tgz",
-          "integrity": "sha1-eCA6TRwyiuHYbcpkYONptX9AVa4="
-        }
-      }
+      "version": "3.2.2",
+      "resolved": "https://registry.npmjs.org/async/-/async-3.2.2.tgz",
+      "integrity": "sha512-H0E+qZaDEfx/FY4t7iLRv1W2fFI6+pyCeTw1uN20AQPiwqwM6ojPxHxdLv4z8hi2DtnW9BOckSspLucW7pIE5g=="
     },
     "async-each": {
       "version": "1.0.1",
@@ -2106,7 +2096,8 @@
         "ansi-regex": {
           "version": "2.1.1",
           "bundled": true,
-          "dev": true
+          "dev": true,
+          "optional": true
         },
         "aproba": {
           "version": "1.1.1",
@@ -2157,7 +2148,8 @@
         "balanced-match": {
           "version": "0.4.2",
           "bundled": true,
-          "dev": true
+          "dev": true,
+          "optional": true
         },
         "bcrypt-pbkdf": {
           "version": "1.0.1",
@@ -2172,6 +2164,7 @@
           "version": "0.0.9",
           "bundled": true,
           "dev": true,
+          "optional": true,
           "requires": {
             "inherits": "~2.0.0"
           }
@@ -2180,6 +2173,7 @@
           "version": "2.10.1",
           "bundled": true,
           "dev": true,
+          "optional": true,
           "requires": {
             "hoek": "2.x.x"
           }
@@ -2188,6 +2182,7 @@
           "version": "1.1.7",
           "bundled": true,
           "dev": true,
+          "optional": true,
           "requires": {
             "balanced-match": "^0.4.1",
             "concat-map": "0.0.1"
@@ -2196,7 +2191,8 @@
         "buffer-shims": {
           "version": "1.0.0",
           "bundled": true,
-          "dev": true
+          "dev": true,
+          "optional": true
         },
         "caseless": {
           "version": "0.12.0",
@@ -2213,12 +2209,14 @@
         "code-point-at": {
           "version": "1.1.0",
           "bundled": true,
-          "dev": true
+          "dev": true,
+          "optional": true
         },
         "combined-stream": {
           "version": "1.0.5",
           "bundled": true,
           "dev": true,
+          "optional": true,
           "requires": {
             "delayed-stream": "~1.0.0"
           }
@@ -2226,22 +2224,26 @@
         "concat-map": {
           "version": "0.0.1",
           "bundled": true,
-          "dev": true
+          "dev": true,
+          "optional": true
         },
         "console-control-strings": {
           "version": "1.1.0",
           "bundled": true,
-          "dev": true
+          "dev": true,
+          "optional": true
         },
         "core-util-is": {
           "version": "1.0.2",
           "bundled": true,
-          "dev": true
+          "dev": true,
+          "optional": true
         },
         "cryptiles": {
           "version": "2.0.5",
           "bundled": true,
           "dev": true,
+          "optional": true,
           "requires": {
             "boom": "2.x.x"
           }
@@ -2281,7 +2283,8 @@
         "delayed-stream": {
           "version": "1.0.0",
           "bundled": true,
-          "dev": true
+          "dev": true,
+          "optional": true
         },
         "delegates": {
           "version": "1.0.0",
@@ -2313,7 +2316,8 @@
         "extsprintf": {
           "version": "1.0.2",
           "bundled": true,
-          "dev": true
+          "dev": true,
+          "optional": true
         },
         "forever-agent": {
           "version": "0.6.1",
@@ -2335,12 +2339,14 @@
         "fs.realpath": {
           "version": "1.0.0",
           "bundled": true,
-          "dev": true
+          "dev": true,
+          "optional": true
         },
         "fstream": {
           "version": "1.0.11",
           "bundled": true,
           "dev": true,
+          "optional": true,
           "requires": {
             "graceful-fs": "^4.1.2",
             "inherits": "~2.0.0",
@@ -2396,6 +2402,7 @@
           "version": "7.1.2",
           "bundled": true,
           "dev": true,
+          "optional": true,
           "requires": {
             "fs.realpath": "^1.0.0",
             "inflight": "^1.0.4",
@@ -2408,7 +2415,8 @@
         "graceful-fs": {
           "version": "4.1.11",
           "bundled": true,
-          "dev": true
+          "dev": true,
+          "optional": true
         },
         "har-schema": {
           "version": "1.0.5",
@@ -2436,6 +2444,7 @@
           "version": "3.1.3",
           "bundled": true,
           "dev": true,
+          "optional": true,
           "requires": {
             "boom": "2.x.x",
             "cryptiles": "2.x.x",
@@ -2446,7 +2455,8 @@
         "hoek": {
           "version": "2.16.3",
           "bundled": true,
-          "dev": true
+          "dev": true,
+          "optional": true
         },
         "http-signature": {
           "version": "1.1.1",
@@ -2463,6 +2473,7 @@
           "version": "1.0.6",
           "bundled": true,
           "dev": true,
+          "optional": true,
           "requires": {
             "once": "^1.3.0",
             "wrappy": "1"
@@ -2471,7 +2482,8 @@
         "inherits": {
           "version": "2.0.3",
           "bundled": true,
-          "dev": true
+          "dev": true,
+          "optional": true
         },
         "ini": {
           "version": "1.3.4",
@@ -2483,6 +2495,7 @@
           "version": "1.0.0",
           "bundled": true,
           "dev": true,
+          "optional": true,
           "requires": {
             "number-is-nan": "^1.0.0"
           }
@@ -2496,7 +2509,8 @@
         "isarray": {
           "version": "1.0.0",
           "bundled": true,
-          "dev": true
+          "dev": true,
+          "optional": true
         },
         "isstream": {
           "version": "0.1.2",
@@ -2569,12 +2583,14 @@
         "mime-db": {
           "version": "1.27.0",
           "bundled": true,
-          "dev": true
+          "dev": true,
+          "optional": true
         },
         "mime-types": {
           "version": "2.1.15",
           "bundled": true,
           "dev": true,
+          "optional": true,
           "requires": {
             "mime-db": "~1.27.0"
           }
@@ -2583,6 +2599,7 @@
           "version": "3.0.4",
           "bundled": true,
           "dev": true,
+          "optional": true,
           "requires": {
             "brace-expansion": "^1.1.7"
           }
@@ -2590,12 +2607,14 @@
         "minimist": {
           "version": "0.0.8",
           "bundled": true,
-          "dev": true
+          "dev": true,
+          "optional": true
         },
         "mkdirp": {
           "version": "0.5.1",
           "bundled": true,
           "dev": true,
+          "optional": true,
           "requires": {
             "minimist": "0.0.8"
           }
@@ -2650,7 +2669,8 @@
         "number-is-nan": {
           "version": "1.0.1",
           "bundled": true,
-          "dev": true
+          "dev": true,
+          "optional": true
         },
         "oauth-sign": {
           "version": "0.8.2",
@@ -2668,6 +2688,7 @@
           "version": "1.4.0",
           "bundled": true,
           "dev": true,
+          "optional": true,
           "requires": {
             "wrappy": "1"
           }
@@ -2697,7 +2718,8 @@
         "path-is-absolute": {
           "version": "1.0.1",
           "bundled": true,
-          "dev": true
+          "dev": true,
+          "optional": true
         },
         "performance-now": {
           "version": "0.2.0",
@@ -2708,7 +2730,8 @@
         "process-nextick-args": {
           "version": "1.0.7",
           "bundled": true,
-          "dev": true
+          "dev": true,
+          "optional": true
         },
         "punycode": {
           "version": "1.4.1",
@@ -2746,6 +2769,7 @@
           "version": "2.2.9",
           "bundled": true,
           "dev": true,
+          "optional": true,
           "requires": {
             "buffer-shims": "~1.0.0",
             "core-util-is": "~1.0.0",
@@ -2790,6 +2814,7 @@
           "version": "2.6.1",
           "bundled": true,
           "dev": true,
+          "optional": true,
           "requires": {
             "glob": "^7.0.5"
           }
@@ -2797,7 +2822,8 @@
         "safe-buffer": {
           "version": "5.0.1",
           "bundled": true,
-          "dev": true
+          "dev": true,
+          "optional": true
         },
         "semver": {
           "version": "5.3.0",
@@ -2821,6 +2847,7 @@
           "version": "1.0.9",
           "bundled": true,
           "dev": true,
+          "optional": true,
           "requires": {
             "hoek": "2.x.x"
           }
@@ -2854,6 +2881,7 @@
           "version": "1.0.2",
           "bundled": true,
           "dev": true,
+          "optional": true,
           "requires": {
             "code-point-at": "^1.0.0",
             "is-fullwidth-code-point": "^1.0.0",
@@ -2864,6 +2892,7 @@
           "version": "1.0.1",
           "bundled": true,
           "dev": true,
+          "optional": true,
           "requires": {
             "safe-buffer": "^5.0.1"
           }
@@ -2878,6 +2907,7 @@
           "version": "3.0.1",
           "bundled": true,
           "dev": true,
+          "optional": true,
           "requires": {
             "ansi-regex": "^2.0.0"
           }
@@ -2892,6 +2922,7 @@
           "version": "2.2.1",
           "bundled": true,
           "dev": true,
+          "optional": true,
           "requires": {
             "block-stream": "*",
             "fstream": "^1.0.2",
@@ -2947,7 +2978,8 @@
         "util-deprecate": {
           "version": "1.0.2",
           "bundled": true,
-          "dev": true
+          "dev": true,
+          "optional": true
         },
         "uuid": {
           "version": "3.0.1",
@@ -2976,7 +3008,8 @@
         "wrappy": {
           "version": "1.0.2",
           "bundled": true,
-          "dev": true
+          "dev": true,
+          "optional": true
         }
       }
     },
@@ -4662,6 +4695,7 @@
           "version": "0.1.4",
           "bundled": true,
           "dev": true,
+          "optional": true,
           "requires": {
             "kind-of": "^3.0.2",
             "longest": "^1.0.1",
@@ -5472,7 +5506,8 @@
         "longest": {
           "version": "1.0.1",
           "bundled": true,
-          "dev": true
+          "dev": true,
+          "optional": true
         },
         "loose-envify": {
           "version": "1.3.1",
@@ -6455,6 +6490,14 @@
             "sprintf-js": "~1.0.2"
           }
         },
+        "async": {
+          "version": "2.6.3",
+          "resolved": "https://registry.npmjs.org/async/-/async-2.6.3.tgz",
+          "integrity": "sha512-zflvls11DCy+dQWzTW2dzuilv8Z5X/pjfmZOWba6TNIVDm+2UDaJmXSOXlasHKfNBs8oo3M0aT50fDEWfKZjXg==",
+          "requires": {
+            "lodash": "^4.17.14"
+          }
+        },
         "esprima": {
           "version": "4.0.0",
           "resolved": "https://registry.npmjs.org/esprima/-/esprima-4.0.0.tgz",
@@ -6469,6 +6512,11 @@
             "esprima": "^4.0.0"
           }
         },
+        "lodash": {
+          "version": "4.17.21",
+          "resolved": "https://registry.npmjs.org/lodash/-/lodash-4.17.21.tgz",
+          "integrity": "sha512-v2kDEe57lecTulaDIuNTPy3Ry4gLGJ6Z1O3vE1krgXZNrsQ+LFTGHVxVjcXPs17LhbZVGedAJv8XZ1tvj5FvSg=="
+        },
         "osm2obj": {
           "version": "2.2.3",
           "resolved": "https://registry.npmjs.org/osm2obj/-/osm2obj-2.2.3.tgz",
diff --git a/package.json b/package.json
index 0c04cee..23f685a 100644
--- a/package.json
+++ b/package.json
@@ -21,7 +21,7 @@
     "@turf/helpers": "^6.0.1",
     "@turf/length": "^5.1.5",
     "@turf/meta": "^6.0.1",
-    "async": "^2.6.0",
+    "async": "^3.2.2",
     "babel-polyfill": "^6.26.0",
     "core-js": "^3.0.0-beta.16",
     "epipebomb": "^1.0.0",