diff --git a/package.json b/package.json
index baa6f55..5bfca78 100644
--- a/package.json
+++ b/package.json
@@ -31,7 +31,7 @@
     "babel-jest": "^19.0.0",
     "babel-preset-es2015": "^6.22.0",
     "babel-preset-stage-1": "^6.22.0",
-    "codecov": "^1.0.1",
+    "codecov": "^3.8.3",
     "eslint": "3.14.1",
     "jest": "^19.0.2",
     "nwb": "^0.15.6"
diff --git a/yarn.lock b/yarn.lock
index 5438e8c..abedb7c 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -18,6 +18,10 @@
     memory-fs "^0.3.0"
     resolve "^1.2.0"
 
+"@tootallnate/once@1":
+  version "1.1.2"
+  resolved "https://registry.yarnpkg.com/@tootallnate/once/-/once-1.1.2.tgz#ccb91445360179a04e7fe6aff78c00ffc1eeaf82"
+
 abab@^1.0.3:
   version "1.0.3"
   resolved "https://registry.yarnpkg.com/abab/-/abab-1.0.3.tgz#b81de5f7274ec4e756d797cd834f303642724e5d"
@@ -63,6 +67,12 @@ after@0.8.2:
   version "0.8.2"
   resolved "https://registry.yarnpkg.com/after/-/after-0.8.2.tgz#fedb394f9f0e02aa9768e702bda23b505fae7e1f"
 
+agent-base@6:
+  version "6.0.2"
+  resolved "https://registry.yarnpkg.com/agent-base/-/agent-base-6.0.2.tgz#49fff58577cfee3f37176feab4c22e00f86d7f77"
+  dependencies:
+    debug "4"
+
 ajv-keywords@^1.0.0, ajv-keywords@^1.1.1:
   version "1.5.1"
   resolved "https://registry.yarnpkg.com/ajv-keywords/-/ajv-keywords-1.5.1.tgz#314dd0a4b3368fad3dfcdc54ede6171b886daf3c"
@@ -142,7 +152,7 @@ argparse@^1.0.7:
   dependencies:
     sprintf-js "~1.0.2"
 
-argv@>=0.0.2:
+argv@0.0.2:
   version "0.0.2"
   resolved "https://registry.yarnpkg.com/argv/-/argv-0.0.2.tgz#ecbd16f8949b157183711b1bda334f37840185ab"
 
@@ -1095,6 +1105,10 @@ balanced-match@^0.4.1, balanced-match@^0.4.2:
   version "0.4.2"
   resolved "https://registry.yarnpkg.com/balanced-match/-/balanced-match-0.4.2.tgz#cb3f3e3c732dc0f01ee70b403f302e61d7709838"
 
+balanced-match@^1.0.0:
+  version "1.0.2"
+  resolved "https://registry.yarnpkg.com/balanced-match/-/balanced-match-1.0.2.tgz#e83e3a7e3f300b34cb9d87f615fa0cbf357690ee"
+
 base64-arraybuffer@0.1.5:
   version "0.1.5"
   resolved "https://registry.yarnpkg.com/base64-arraybuffer/-/base64-arraybuffer-0.1.5.tgz#73926771923b5a19747ad666aa5cd4bf9c6e9ce8"
@@ -1181,6 +1195,13 @@ brace-expansion@^1.0.0:
     balanced-match "^0.4.1"
     concat-map "0.0.1"
 
+brace-expansion@^1.1.7:
+  version "1.1.11"
+  resolved "https://registry.yarnpkg.com/brace-expansion/-/brace-expansion-1.1.11.tgz#3c7fcbf529d87226f3d2f52b966ff5271eb441dd"
+  dependencies:
+    balanced-match "^1.0.0"
+    concat-map "0.0.1"
+
 braces@^0.1.2:
   version "0.1.5"
   resolved "https://registry.yarnpkg.com/braces/-/braces-0.1.5.tgz#c085711085291d8b75fdd74eab0f8597280711e6"
@@ -1488,14 +1509,15 @@ code-point-at@^1.0.0:
   version "1.1.0"
   resolved "https://registry.yarnpkg.com/code-point-at/-/code-point-at-1.1.0.tgz#0d070b4d043a5bea33a2f1a40e2edb3d9a4ccf77"
 
-codecov@^1.0.1:
-  version "1.0.1"
-  resolved "https://registry.yarnpkg.com/codecov/-/codecov-1.0.1.tgz#97260ceac0e96b8eda8d562006558a53a139dffd"
+codecov@^3.8.3:
+  version "3.8.3"
+  resolved "https://registry.yarnpkg.com/codecov/-/codecov-3.8.3.tgz#9c3e364b8a700c597346ae98418d09880a3fdbe7"
   dependencies:
-    argv ">=0.0.2"
-    execSync "1.0.2"
-    request ">=2.42.0"
-    urlgrey ">=0.4.0"
+    argv "0.0.2"
+    ignore-walk "3.0.4"
+    js-yaml "3.14.1"
+    teeny-request "7.1.1"
+    urlgrey "1.0.0"
 
 color-convert@^1.0.0, color-convert@^1.3.0:
   version "1.9.0"
@@ -1912,6 +1934,12 @@ debug@2.6.1:
   dependencies:
     ms "0.7.2"
 
+debug@4:
+  version "4.3.4"
+  resolved "https://registry.yarnpkg.com/debug/-/debug-4.3.4.tgz#1319f6579357f2338d3337d2cdd4914bb5dcc865"
+  dependencies:
+    ms "2.1.2"
+
 decamelize@^1.0.0, decamelize@^1.1.1, decamelize@^1.1.2:
   version "1.2.0"
   resolved "https://registry.yarnpkg.com/decamelize/-/decamelize-1.2.0.tgz#f6534d15148269b20352e7bee26f501f9a191290"
@@ -2341,9 +2369,9 @@ esprima@2.7.x, esprima@^2.6.0, esprima@^2.7.1:
   version "2.7.3"
   resolved "https://registry.yarnpkg.com/esprima/-/esprima-2.7.3.tgz#96e3b70d5779f6ad49cd032673d1c312767ba581"
 
-esprima@^3.1.1:
-  version "3.1.3"
-  resolved "https://registry.yarnpkg.com/esprima/-/esprima-3.1.3.tgz#fdca51cee6133895e3c88d535ce49dbff62a4633"
+esprima@^4.0.0:
+  version "4.0.1"
+  resolved "https://registry.yarnpkg.com/esprima/-/esprima-4.0.1.tgz#13b04cdb3e6c5d19df91ab6987a8695619b0aa71"
 
 esrecurse@^4.1.0:
   version "4.1.0"
@@ -2403,12 +2431,6 @@ exec-sh@^0.2.0:
   dependencies:
     merge "^1.1.3"
 
-execSync@1.0.2:
-  version "1.0.2"
-  resolved "https://registry.yarnpkg.com/execSync/-/execSync-1.0.2.tgz#1f42eda582225180053224ecdd3fd1960fdb3139"
-  dependencies:
-    temp "~0.5.1"
-
 exit-hook@^1.0.0:
   version "1.1.1"
   resolved "https://registry.yarnpkg.com/exit-hook/-/exit-hook-1.1.1.tgz#f05ca233b48c05d54fff07765df8507e95c02ff8"
@@ -2516,6 +2538,12 @@ fast-levenshtein@~2.0.4:
   version "2.0.6"
   resolved "https://registry.yarnpkg.com/fast-levenshtein/-/fast-levenshtein-2.0.6.tgz#3d8a5c66883a16a30ca8643e851f19baa7797917"
 
+fast-url-parser@^1.1.3:
+  version "1.1.3"
+  resolved "https://registry.yarnpkg.com/fast-url-parser/-/fast-url-parser-1.1.3.tgz#f4af3ea9f34d8a271cf58ad2b3759f431f0b318d"
+  dependencies:
+    punycode "^1.3.2"
+
 fastparse@^1.1.1:
   version "1.1.1"
   resolved "https://registry.yarnpkg.com/fastparse/-/fastparse-1.1.1.tgz#d1e2643b38a94d7583b479060e6c4affc94071f8"
@@ -2857,10 +2885,6 @@ graceful-fs@^4.1.2, graceful-fs@^4.1.3, graceful-fs@^4.1.4, graceful-fs@^4.1.6,
   version "4.1.11"
   resolved "https://registry.yarnpkg.com/graceful-fs/-/graceful-fs-4.1.11.tgz#0e8bdfe4d1ddb8854d64e04ea7c00e2a026e5658"
 
-graceful-fs@~1:
-  version "1.2.3"
-  resolved "https://registry.yarnpkg.com/graceful-fs/-/graceful-fs-1.2.3.tgz#15a4806a57547cb2d2dbf27f42e89a8c3451b364"
-
 "graceful-readlink@>= 1.0.0":
   version "1.0.1"
   resolved "https://registry.yarnpkg.com/graceful-readlink/-/graceful-readlink-1.0.1.tgz#4cafad76bc62f02fa039b2f94e9a3dd3a391a725"
@@ -3041,6 +3065,14 @@ http-errors@~1.6.1:
     setprototypeof "1.0.3"
     statuses ">= 1.3.1 < 2"
 
+http-proxy-agent@^4.0.0:
+  version "4.0.1"
+  resolved "https://registry.yarnpkg.com/http-proxy-agent/-/http-proxy-agent-4.0.1.tgz#8a8c8ef7f5932ccf953c296ca8291b95aa74aa3a"
+  dependencies:
+    "@tootallnate/once" "1"
+    agent-base "6"
+    debug "4"
+
 http-proxy@^1.13.0:
   version "1.16.2"
   resolved "https://registry.yarnpkg.com/http-proxy/-/http-proxy-1.16.2.tgz#06dff292952bf64dbe8471fa9df73066d4f37742"
@@ -3060,6 +3092,13 @@ https-browserify@0.0.1:
   version "0.0.1"
   resolved "https://registry.yarnpkg.com/https-browserify/-/https-browserify-0.0.1.tgz#3f91365cabe60b77ed0ebba24b454e3e09d95a82"
 
+https-proxy-agent@^5.0.0:
+  version "5.0.1"
+  resolved "https://registry.yarnpkg.com/https-proxy-agent/-/https-proxy-agent-5.0.1.tgz#c59ef224a04fe8b754f3db0063a25ea30d0005d6"
+  dependencies:
+    agent-base "6"
+    debug "4"
+
 iconv-lite@0.4.13:
   version "0.4.13"
   resolved "https://registry.yarnpkg.com/iconv-lite/-/iconv-lite-0.4.13.tgz#1f88aba4ab0b1508e8312acc39345f36e992e2f2"
@@ -3076,6 +3115,12 @@ ieee754@^1.1.4:
   version "1.1.8"
   resolved "https://registry.yarnpkg.com/ieee754/-/ieee754-1.1.8.tgz#be33d40ac10ef1926701f6f08a2d86fbfd1ad3e4"
 
+ignore-walk@3.0.4:
+  version "3.0.4"
+  resolved "https://registry.yarnpkg.com/ignore-walk/-/ignore-walk-3.0.4.tgz#c9a09f69b7c7b479a5d74ac1a3c0d4236d2a6335"
+  dependencies:
+    minimatch "^3.0.4"
+
 ignore@^3.2.0:
   version "3.2.4"
   resolved "https://registry.yarnpkg.com/ignore/-/ignore-3.2.4.tgz#4055e03596729a8fabe45a43c100ad5ed815c4e8"
@@ -3721,12 +3766,12 @@ js-tokens@^3.0.0:
   version "3.0.1"
   resolved "https://registry.yarnpkg.com/js-tokens/-/js-tokens-3.0.1.tgz#08e9f132484a2c45a30907e9dc4d5567b7f114d7"
 
-js-yaml@3.x, js-yaml@^3.4.3, js-yaml@^3.5.1, js-yaml@^3.7.0:
-  version "3.8.2"
-  resolved "https://registry.yarnpkg.com/js-yaml/-/js-yaml-3.8.2.tgz#02d3e2c0f6beab20248d412c352203827d786721"
+js-yaml@3.14.1, js-yaml@3.x, js-yaml@^3.4.3, js-yaml@^3.5.1, js-yaml@^3.7.0:
+  version "3.14.1"
+  resolved "https://registry.yarnpkg.com/js-yaml/-/js-yaml-3.14.1.tgz#dae812fdb3825fa306609a8717383c50c36a0537"
   dependencies:
     argparse "^1.0.7"
-    esprima "^3.1.1"
+    esprima "^4.0.0"
 
 js-yaml@~3.7.0:
   version "3.7.0"
@@ -4241,6 +4286,12 @@ minimalistic-crypto-utils@^1.0.0, minimalistic-crypto-utils@^1.0.1:
   dependencies:
     brace-expansion "^1.0.0"
 
+minimatch@^3.0.4:
+  version "3.1.2"
+  resolved "https://registry.yarnpkg.com/minimatch/-/minimatch-3.1.2.tgz#19cd194bfd3e428f049a70817c038d89ab4be35b"
+  dependencies:
+    brace-expansion "^1.1.7"
+
 minimist@0.0.8, minimist@~0.0.1:
   version "0.0.8"
   resolved "https://registry.yarnpkg.com/minimist/-/minimist-0.0.8.tgz#857fcabfc3397d2625b8228262e86aa7a011b05d"
@@ -4289,6 +4340,10 @@ ms@0.7.2:
   version "0.7.2"
   resolved "https://registry.yarnpkg.com/ms/-/ms-0.7.2.tgz#ae25cf2512b3885a1d95d7f037868d8431124765"
 
+ms@2.1.2:
+  version "2.1.2"
+  resolved "https://registry.yarnpkg.com/ms/-/ms-2.1.2.tgz#d09d1f357b443f493382a8eb3ccd183872ae6009"
+
 mute-stream@0.0.5:
   version "0.0.5"
   resolved "https://registry.yarnpkg.com/mute-stream/-/mute-stream-0.0.5.tgz#8fbfabb0a98a253d3184331f9e8deb7372fac6c0"
@@ -4327,6 +4382,12 @@ node-dir@^0.1.10:
   dependencies:
     minimatch "^3.0.2"
 
+node-fetch@^2.6.1:
+  version "2.6.7"
+  resolved "https://registry.yarnpkg.com/node-fetch/-/node-fetch-2.6.7.tgz#24de9fba827e3b4ae44dc8b20256a379160052ad"
+  dependencies:
+    whatwg-url "^5.0.0"
+
 node-int64@^0.4.0:
   version "0.4.0"
   resolved "https://registry.yarnpkg.com/node-int64/-/node-int64-0.4.0.tgz#87a9065cdb355d3182d8f94ce11188b825c68a3b"
@@ -5171,7 +5232,7 @@ punycode@1.3.2:
   version "1.3.2"
   resolved "https://registry.yarnpkg.com/punycode/-/punycode-1.3.2.tgz#9653a036fb7c1ee42342f2325cceefea3926c48d"
 
-punycode@^1.2.4, punycode@^1.4.1:
+punycode@^1.2.4, punycode@^1.3.2, punycode@^1.4.1:
   version "1.4.1"
   resolved "https://registry.yarnpkg.com/punycode/-/punycode-1.4.1.tgz#c0d5a63b2718800ad8e1eb0fa5269c84dd41845e"
 
@@ -5460,7 +5521,7 @@ request-progress@~2.0.1:
   dependencies:
     throttleit "^1.0.0"
 
-request@>=2.42.0, request@^2.79.0, request@~2.79.0:
+request@^2.79.0, request@~2.79.0:
   version "2.79.0"
   resolved "https://registry.yarnpkg.com/request/-/request-2.79.0.tgz#4dfe5bf6be8b8cdc37fcf93e04b65577722710de"
   dependencies:
@@ -5546,12 +5607,6 @@ rimraf@2, rimraf@2.5.4, rimraf@^2.2.8, rimraf@^2.3.3, rimraf@^2.4.3, rimraf@^2.4
   dependencies:
     glob "^7.0.5"
 
-rimraf@~2.1.4:
-  version "2.1.4"
-  resolved "https://registry.yarnpkg.com/rimraf/-/rimraf-2.1.4.tgz#5a6eb62eeda068f51ede50f29b3e5cd22f3d9bb2"
-  optionalDependencies:
-    graceful-fs "~1"
-
 ripemd160@^1.0.0:
   version "1.0.1"
   resolved "https://registry.yarnpkg.com/ripemd160/-/ripemd160-1.0.1.tgz#93a4bbd4942bc574b69a8fa57c71de10ecca7d6e"
@@ -5859,6 +5914,12 @@ stream-browserify@^2.0.1:
     inherits "~2.0.1"
     readable-stream "^2.0.2"
 
+stream-events@^1.0.5:
+  version "1.0.5"
+  resolved "https://registry.yarnpkg.com/stream-events/-/stream-events-1.0.5.tgz#bbc898ec4df33a4902d892333d47da9bf1c406d5"
+  dependencies:
+    stubs "^3.0.0"
+
 stream-http@^2.3.1:
   version "2.6.3"
   resolved "https://registry.yarnpkg.com/stream-http/-/stream-http-2.6.3.tgz#4c3ddbf9635968ea2cfd4e48d43de5def2625ac3"
@@ -5928,6 +5989,10 @@ strip-json-comments@~2.0.1:
   version "2.0.1"
   resolved "https://registry.yarnpkg.com/strip-json-comments/-/strip-json-comments-2.0.1.tgz#3c531942e908c2697c0ec344858c286c7ca0a60a"
 
+stubs@^3.0.0:
+  version "3.0.0"
+  resolved "https://registry.yarnpkg.com/stubs/-/stubs-3.0.0.tgz#e8d2ba1fa9c90570303c030b6900f7d5f89abe5b"
+
 style-loader@0.13.1:
   version "0.13.1"
   resolved "https://registry.yarnpkg.com/style-loader/-/style-loader-0.13.1.tgz#468280efbc0473023cd3a6cd56e33b5a1d7fc3a9"
@@ -6002,11 +6067,15 @@ tar@~2.2.1:
     fstream "^1.0.2"
     inherits "2"
 
-temp@~0.5.1:
-  version "0.5.1"
-  resolved "https://registry.yarnpkg.com/temp/-/temp-0.5.1.tgz#77ab19c79aa7b593cbe4fac2441768cad987b8df"
+teeny-request@7.1.1:
+  version "7.1.1"
+  resolved "https://registry.yarnpkg.com/teeny-request/-/teeny-request-7.1.1.tgz#2b0d156f4a8ad81de44303302ba8d7f1f05e20e6"
   dependencies:
-    rimraf "~2.1.4"
+    http-proxy-agent "^4.0.0"
+    https-proxy-agent "^5.0.0"
+    node-fetch "^2.6.1"
+    stream-events "^1.0.5"
+    uuid "^8.0.0"
 
 test-exclude@^3.3.0:
   version "3.3.0"
@@ -6200,9 +6269,11 @@ url@^0.11.0:
     punycode "1.3.2"
     querystring "0.2.0"
 
-urlgrey@>=0.4.0:
-  version "0.4.4"
-  resolved "https://registry.yarnpkg.com/urlgrey/-/urlgrey-0.4.4.tgz#892fe95960805e85519f1cd4389f2cb4cbb7652f"
+urlgrey@1.0.0:
+  version "1.0.0"
+  resolved "https://registry.yarnpkg.com/urlgrey/-/urlgrey-1.0.0.tgz#72d2f904482d0b602e3c7fa599343d699bbe1017"
+  dependencies:
+    fast-url-parser "^1.1.3"
 
 user-home@^1.1.1:
   version "1.1.1"
@@ -6247,6 +6318,10 @@ uuid@^3.0.0:
   version "3.0.1"
   resolved "https://registry.yarnpkg.com/uuid/-/uuid-3.0.1.tgz#6544bba2dfda8c1cf17e629a3a305e2bb1fee6c1"
 
+uuid@^8.0.0:
+  version "8.3.2"
+  resolved "https://registry.yarnpkg.com/uuid/-/uuid-8.3.2.tgz#80d5b5ced271bb9af6c445f21a1a04c606cefbe2"
+
 v8flags@^2.0.10:
   version "2.0.11"
   resolved "https://registry.yarnpkg.com/v8flags/-/v8flags-2.0.11.tgz#bca8f30f0d6d60612cc2c00641e6962d42ae6881"
@@ -6389,6 +6464,13 @@ whatwg-url@^4.3.0:
     tr46 "~0.0.3"
     webidl-conversions "^3.0.0"
 
+whatwg-url@^5.0.0:
+  version "5.0.0"
+  resolved "https://registry.yarnpkg.com/whatwg-url/-/whatwg-url-5.0.0.tgz#966454e8765462e37644d3626f6742ce8b70965d"
+  dependencies:
+    tr46 "~0.0.3"
+    webidl-conversions "^3.0.0"
+
 whet.extend@~0.9.9:
   version "0.9.9"
   resolved "https://registry.yarnpkg.com/whet.extend/-/whet.extend-0.9.9.tgz#f877d5bf648c97e5aa542fadc16d6a259b9c11a1"