diff --git a/package.json b/package.json
index b754551..9880d7c 100644
--- a/package.json
+++ b/package.json
@@ -53,7 +53,7 @@
     "babel-eslint": "^7.2.3",
     "babel-plugin-dynamic-import-node": "^1.0.2",
     "babel-preset-env": "^1.5.2",
-    "codecov": "^2.2.0",
+    "codecov": "^3.7.1",
     "conventional-changelog-cli": "^1.3.1",
     "del-cli": "^1.0.0",
     "eslint": "^3.19.0",
diff --git a/yarn.lock b/yarn.lock
index 44d38f5..84c69d5 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -2,6 +2,10 @@
 # yarn lockfile v1
 
 
+"@tootallnate/once@1":
+  version "1.1.2"
+  resolved "https://registry.yarnpkg.com/@tootallnate/once/-/once-1.1.2.tgz#ccb91445360179a04e7fe6aff78c00ffc1eeaf82"
+
 JSONStream@^1.0.4:
   version "1.3.1"
   resolved "https://registry.yarnpkg.com/JSONStream/-/JSONStream-1.3.1.tgz#707f761e01dae9e16f1bcf93703b78c70966579a"
@@ -45,6 +49,16 @@ add-stream@^1.0.0:
   version "1.0.0"
   resolved "https://registry.yarnpkg.com/add-stream/-/add-stream-1.0.0.tgz#6a7990437ca736d5e1288db92bd3266d5f5cb2aa"
 
+agent-base@5:
+  version "5.1.1"
+  resolved "https://registry.yarnpkg.com/agent-base/-/agent-base-5.1.1.tgz#e8fb3f242959db44d63be665db7a8e739537a32c"
+
+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:
   version "1.5.1"
   resolved "https://registry.yarnpkg.com/ajv-keywords/-/ajv-keywords-1.5.1.tgz#314dd0a4b3368fad3dfcdc54ede6171b886daf3c"
@@ -879,10 +893,6 @@ capture-stack-trace@^1.0.0:
   version "1.0.0"
   resolved "https://registry.yarnpkg.com/capture-stack-trace/-/capture-stack-trace-1.0.0.tgz#4a6fa07399c26bba47f0b2496b4d0fb408c5550d"
 
-caseless@~0.11.0:
-  version "0.11.0"
-  resolved "https://registry.yarnpkg.com/caseless/-/caseless-0.11.0.tgz#715b96ea9841593cc33067923f5ec60ebda4f7d7"
-
 caseless@~0.12.0:
   version "0.12.0"
   resolved "https://registry.yarnpkg.com/caseless/-/caseless-0.12.0.tgz#1b681c21ff84033c826543090689420d187151dc"
@@ -990,12 +1000,14 @@ 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@^2.2.0:
-  version "2.2.0"
-  resolved "https://registry.yarnpkg.com/codecov/-/codecov-2.2.0.tgz#2d06817ceb8891eca6368836d4fb6bf6cc04ffd1"
+codecov@^3.7.1:
+  version "3.7.1"
+  resolved "https://registry.yarnpkg.com/codecov/-/codecov-3.7.1.tgz#434cb8d55f18ef01672e5739d3d266696bebc202"
   dependencies:
     argv "0.0.2"
-    request "2.79.0"
+    ignore-walk "3.0.3"
+    js-yaml "3.13.1"
+    teeny-request "6.0.1"
     urlgrey "0.4.4"
 
 color-convert@^1.0.0:
@@ -1304,6 +1316,12 @@ dateformat@^1.0.11, dateformat@^1.0.12:
     get-stdin "^4.0.1"
     meow "^3.3.0"
 
+debug@4:
+  version "4.3.1"
+  resolved "https://registry.yarnpkg.com/debug/-/debug-4.3.1.tgz#f0d229c505e0c6d8c49ac553d1b13dc183f6b2ee"
+  dependencies:
+    ms "2.1.2"
+
 debug@^2.1.1, debug@^2.2.0, debug@^2.6.3, debug@^2.6.8:
   version "2.6.8"
   resolved "https://registry.yarnpkg.com/debug/-/debug-2.6.8.tgz#e731531ca2ede27d188222427da17821d68ff4fc"
@@ -1613,9 +1631,9 @@ 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"
 
 esquery@^1.0.0:
   version "1.0.0"
@@ -2046,15 +2064,6 @@ har-schema@^1.0.5:
   version "1.0.5"
   resolved "https://registry.yarnpkg.com/har-schema/-/har-schema-1.0.5.tgz#d263135f43307c02c602afc8fe95970c0151369e"
 
-har-validator@~2.0.6:
-  version "2.0.6"
-  resolved "https://registry.yarnpkg.com/har-validator/-/har-validator-2.0.6.tgz#cdcbc08188265ad119b6a5a7c8ab70eecfb5d27d"
-  dependencies:
-    chalk "^1.1.1"
-    commander "^2.9.0"
-    is-my-json-valid "^2.12.4"
-    pinkie-promise "^2.0.0"
-
 har-validator@~4.2.1:
   version "4.2.1"
   resolved "https://registry.yarnpkg.com/har-validator/-/har-validator-4.2.1.tgz#33481d0f1bbff600dd203d75812a6a5fba002e2a"
@@ -2112,6 +2121,14 @@ html-encoding-sniffer@^1.0.1:
   dependencies:
     whatwg-encoding "^1.0.1"
 
+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-signature@~1.1.0:
   version "1.1.1"
   resolved "https://registry.yarnpkg.com/http-signature/-/http-signature-1.1.1.tgz#df72e267066cd0ac67fb76adf8e134a8fbcf91bf"
@@ -2120,6 +2137,13 @@ http-signature@~1.1.0:
     jsprim "^1.2.2"
     sshpk "^1.7.0"
 
+https-proxy-agent@^4.0.0:
+  version "4.0.0"
+  resolved "https://registry.yarnpkg.com/https-proxy-agent/-/https-proxy-agent-4.0.0.tgz#702b71fb5520a132a66de1f67541d9e62154d82b"
+  dependencies:
+    agent-base "5"
+    debug "4"
+
 husky@^0.14.0:
   version "0.14.0"
   resolved "https://registry.yarnpkg.com/husky/-/husky-0.14.0.tgz#d0115459d824e7cc67dbc23231935ba9cfdf0989"
@@ -2132,6 +2156,12 @@ iconv-lite@0.4.13:
   version "0.4.13"
   resolved "https://registry.yarnpkg.com/iconv-lite/-/iconv-lite-0.4.13.tgz#1f88aba4ab0b1508e8312acc39345f36e992e2f2"
 
+ignore-walk@3.0.3:
+  version "3.0.3"
+  resolved "https://registry.yarnpkg.com/ignore-walk/-/ignore-walk-3.0.3.tgz#017e2447184bfeade7c238e4aefdd1e8f95b1e37"
+  dependencies:
+    minimatch "^3.0.4"
+
 ignore@^3.2.0:
   version "3.3.3"
   resolved "https://registry.yarnpkg.com/ignore/-/ignore-3.3.3.tgz#432352e57accd87ab3110e82d3fea0e47812156d"
@@ -2267,7 +2297,7 @@ is-glob@^2.0.0, is-glob@^2.0.1:
   dependencies:
     is-extglob "^1.0.0"
 
-is-my-json-valid@^2.10.0, is-my-json-valid@^2.12.4:
+is-my-json-valid@^2.10.0:
   version "2.16.0"
   resolved "https://registry.yarnpkg.com/is-my-json-valid/-/is-my-json-valid-2.16.0.tgz#f079dd9bfdae65ee2038aae8acbc86ab109e3693"
   dependencies:
@@ -2660,12 +2690,12 @@ 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@^3.4.3, js-yaml@^3.5.1, js-yaml@^3.7.0:
-  version "3.8.4"
-  resolved "https://registry.yarnpkg.com/js-yaml/-/js-yaml-3.8.4.tgz#520b4564f86573ba96662af85a8cafa7b4b5a6f6"
+js-yaml@3.13.1, js-yaml@^3.4.3, js-yaml@^3.5.1, js-yaml@^3.7.0:
+  version "3.13.1"
+  resolved "https://registry.yarnpkg.com/js-yaml/-/js-yaml-3.13.1.tgz#aff151b30bfdfa8e49e05da22e7415e9dfa37847"
   dependencies:
     argparse "^1.0.7"
-    esprima "^3.1.1"
+    esprima "^4.0.0"
 
 jsbn@~0.1.0:
   version "0.1.1"
@@ -3039,6 +3069,10 @@ ms@2.0.0:
   version "2.0.0"
   resolved "https://registry.yarnpkg.com/ms/-/ms-2.0.0.tgz#5608aeadfc00be6c2901df5f9861788de0d597c8"
 
+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"
@@ -3051,6 +3085,10 @@ natural-compare@^1.4.0:
   version "1.4.0"
   resolved "https://registry.yarnpkg.com/natural-compare/-/natural-compare-1.4.0.tgz#4abebfeed7541f2c27acfb29bdbbd15c8d5ba4f7"
 
+node-fetch@^2.2.0:
+  version "2.6.1"
+  resolved "https://registry.yarnpkg.com/node-fetch/-/node-fetch-2.6.1.tgz#045bd323631f76ed2e2b55573394416b639a0052"
+
 node-int64@^0.4.0:
   version "0.4.0"
   resolved "https://registry.yarnpkg.com/node-int64/-/node-int64-0.4.0.tgz#87a9065cdb355d3182d8f94ce11188b825c68a3b"
@@ -3435,10 +3473,6 @@ q@^1.4.1:
   version "1.5.0"
   resolved "https://registry.yarnpkg.com/q/-/q-1.5.0.tgz#dd01bac9d06d30e6f219aecb8253ee9ebdc308f1"
 
-qs@~6.3.0:
-  version "6.3.2"
-  resolved "https://registry.yarnpkg.com/qs/-/qs-6.3.2.tgz#e75bd5f6e268122a2a0e0bda630b2550c166502c"
-
 qs@~6.4.0:
   version "6.4.0"
   resolved "https://registry.yarnpkg.com/qs/-/qs-6.4.0.tgz#13e26d28ad6b0ffaa91312cd3bf708ed351e7233"
@@ -3603,31 +3637,6 @@ repeating@^2.0.0:
   dependencies:
     is-finite "^1.0.0"
 
-request@2.79.0:
-  version "2.79.0"
-  resolved "https://registry.yarnpkg.com/request/-/request-2.79.0.tgz#4dfe5bf6be8b8cdc37fcf93e04b65577722710de"
-  dependencies:
-    aws-sign2 "~0.6.0"
-    aws4 "^1.2.1"
-    caseless "~0.11.0"
-    combined-stream "~1.0.5"
-    extend "~3.0.0"
-    forever-agent "~0.6.1"
-    form-data "~2.1.1"
-    har-validator "~2.0.6"
-    hawk "~3.1.3"
-    http-signature "~1.1.0"
-    is-typedarray "~1.0.0"
-    isstream "~0.1.2"
-    json-stringify-safe "~5.0.1"
-    mime-types "~2.1.7"
-    oauth-sign "~0.8.1"
-    qs "~6.3.0"
-    stringstream "~0.0.4"
-    tough-cookie "~2.3.0"
-    tunnel-agent "~0.4.1"
-    uuid "^3.0.0"
-
 request@^2.79.0, request@^2.81.0:
   version "2.81.0"
   resolved "https://registry.yarnpkg.com/request/-/request-2.81.0.tgz#c6928946a0e06c5f8d6f8a9333469ffda46298a0"
@@ -3882,6 +3891,12 @@ staged-git-files@0.0.4:
   version "0.0.4"
   resolved "https://registry.yarnpkg.com/staged-git-files/-/staged-git-files-0.0.4.tgz#d797e1b551ca7a639dec0237dc6eb4bb9be17d35"
 
+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-to-observable@^0.1.0:
   version "0.1.0"
   resolved "https://registry.yarnpkg.com/stream-to-observable/-/stream-to-observable-0.1.0.tgz#45bf1d9f2d7dc09bed81f1c307c430e68b84cffe"
@@ -3951,6 +3966,10 @@ 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"
+
 supports-color@^2.0.0:
   version "2.0.0"
   resolved "https://registry.yarnpkg.com/supports-color/-/supports-color-2.0.0.tgz#535d045ce6b6363fa40117084629995e9df324c7"
@@ -4019,6 +4038,16 @@ tar@^2.2.1:
     fstream "^1.0.2"
     inherits "2"
 
+teeny-request@6.0.1:
+  version "6.0.1"
+  resolved "https://registry.yarnpkg.com/teeny-request/-/teeny-request-6.0.1.tgz#9b1f512cef152945827ba7e34f62523a4ce2c5b0"
+  dependencies:
+    http-proxy-agent "^4.0.0"
+    https-proxy-agent "^4.0.0"
+    node-fetch "^2.2.0"
+    stream-events "^1.0.5"
+    uuid "^3.3.2"
+
 tempfile@^1.1.1:
   version "1.1.1"
   resolved "https://registry.yarnpkg.com/tempfile/-/tempfile-1.1.1.tgz#5bcc4eaecc4ab2c707d8bc11d99ccc9a2cb287f2"
@@ -4109,10 +4138,6 @@ tunnel-agent@^0.6.0:
   dependencies:
     safe-buffer "^5.0.1"
 
-tunnel-agent@~0.4.1:
-  version "0.4.3"
-  resolved "https://registry.yarnpkg.com/tunnel-agent/-/tunnel-agent-0.4.3.tgz#6373db76909fe570e08d73583365ed828a74eeeb"
-
 tweetnacl@^0.14.3, tweetnacl@~0.14.0:
   version "0.14.5"
   resolved "https://registry.yarnpkg.com/tweetnacl/-/tweetnacl-0.14.5.tgz#5ae68177f192d4456269d108afa93ff8743f4f64"
@@ -4199,6 +4224,10 @@ uuid@^3.0.0:
   version "3.1.0"
   resolved "https://registry.yarnpkg.com/uuid/-/uuid-3.1.0.tgz#3dd3d3e790abc24d7b0d3a034ffababe28ebbc04"
 
+uuid@^3.3.2:
+  version "3.4.0"
+  resolved "https://registry.yarnpkg.com/uuid/-/uuid-3.4.0.tgz#b23e4358afa8a202fe7a100af1f5f883f02007ee"
+
 v8flags@^2.0.10:
   version "2.1.1"
   resolved "https://registry.yarnpkg.com/v8flags/-/v8flags-2.1.1.tgz#aab1a1fa30d45f88dd321148875ac02c0b55e5b4"