diff --git a/package.json b/package.json
index 8718acde..1332a041 100644
--- a/package.json
+++ b/package.json
@@ -9,8 +9,8 @@
   "scripts": {
     "build": "yarn build-js-all && yarn copy-styles && yarn build-styles",
     "build-js-all": "yarn build-js-esm && yarn build-js-umd",
-    "build-js-esm": "BABEL_ENV=production-esm babel src -d dist/esm --ignore **/*.spec.js,**/*.spec.jsx",
-    "build-js-umd": "BABEL_ENV=production-umd babel src -d dist/umd --ignore **/*.spec.js,**/*.spec.jsx",
+    "build-js-esm": "cross-env BABEL_ENV=production-esm babel src -d dist/esm --ignore **/*.spec.js,**/*.spec.jsx",
+    "build-js-umd": "cross-env BABEL_ENV=production-umd babel src -d dist/umd --ignore **/*.spec.js,**/*.spec.jsx",
     "build-styles": "yarn build-styles-esm && yarn build-styles-umd",
     "build-styles-esm": "lessc ./dist/esm/Calendar.less ./dist/esm/Calendar.css",
     "build-styles-umd": "lessc ./dist/umd/Calendar.less ./dist/umd/Calendar.css",
@@ -86,6 +86,7 @@
     "@babel/preset-react": "^7.0.0",
     "babel-eslint": "^10.0.0",
     "babel-jest": "^24.0.0",
+    "cross-env": "^6.0.3",
     "enzyme": "^3.10.0",
     "enzyme-adapter-react-16": "^1.14.0",
     "eslint": "^6.1.0",
diff --git a/yarn.lock b/yarn.lock
index 18f6cced..978d4837 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -1604,6 +1604,13 @@ core-util-is@1.0.2, core-util-is@~1.0.0:
   resolved "https://registry.yarnpkg.com/core-util-is/-/core-util-is-1.0.2.tgz#b5fd54220aa2bc5ab57aab7140c940754503c1a7"
   integrity sha1-tf1UIgqivFq1eqtxQMlAdUUDwac=
 
+cross-env@^6.0.3:
+  version "6.0.3"
+  resolved "https://registry.yarnpkg.com/cross-env/-/cross-env-6.0.3.tgz#4256b71e49b3a40637a0ce70768a6ef5c72ae941"
+  integrity sha512-+KqxF6LCvfhWvADcDPqo64yVIB31gv/jQulX2NGzKS/g3GEVz6/pt4wjHFtFWsHMddebWD/sDthJemzM4MaAag==
+  dependencies:
+    cross-spawn "^7.0.0"
+
 cross-spawn@^6.0.0, cross-spawn@^6.0.5:
   version "6.0.5"
   resolved "https://registry.yarnpkg.com/cross-spawn/-/cross-spawn-6.0.5.tgz#4a5ec7c64dfae22c3a14124dbacdee846d80cbc4"
@@ -1615,6 +1622,15 @@ cross-spawn@^6.0.0, cross-spawn@^6.0.5:
     shebang-command "^1.2.0"
     which "^1.2.9"
 
+cross-spawn@^7.0.0:
+  version "7.0.1"
+  resolved "https://registry.yarnpkg.com/cross-spawn/-/cross-spawn-7.0.1.tgz#0ab56286e0f7c24e153d04cc2aa027e43a9a5d14"
+  integrity sha512-u7v4o84SwFpD32Z8IIcPZ6z1/ie24O6RU3RbtL5Y316l3KuHVPx9ItBgWQ6VlfAFnRnTtMUrsQ9MUUTuEZjogg==
+  dependencies:
+    path-key "^3.1.0"
+    shebang-command "^2.0.0"
+    which "^2.0.1"
+
 css-select@~1.2.0:
   version "1.2.0"
   resolved "https://registry.yarnpkg.com/css-select/-/css-select-1.2.0.tgz#2b3a110539c5355f1cd8d314623e870b121ec858"
@@ -4240,6 +4256,11 @@ path-key@^2.0.0, path-key@^2.0.1:
   resolved "https://registry.yarnpkg.com/path-key/-/path-key-2.0.1.tgz#411cadb574c5a140d3a4b1910d40d80cc9f40b40"
   integrity sha1-QRyttXTFoUDTpLGRDUDYDMn0C0A=
 
+path-key@^3.1.0:
+  version "3.1.1"
+  resolved "https://registry.yarnpkg.com/path-key/-/path-key-3.1.1.tgz#581f6ade658cbba65a0d3380de7753295054f375"
+  integrity sha512-ojmeN0qd+y0jszEtoY48r0Peq5dwMEkIlCOu6Q5f41lfkswXuKtYrhgoTpLnyIcHm24Uhqx+5Tqm2InSwLhE6Q==
+
 path-parse@^1.0.6:
   version "1.0.6"
   resolved "https://registry.yarnpkg.com/path-parse/-/path-parse-1.0.6.tgz#d62dbb5679405d72c4737ec58600e9ddcf06d24c"
@@ -4851,11 +4872,23 @@ shebang-command@^1.2.0:
   dependencies:
     shebang-regex "^1.0.0"
 
+shebang-command@^2.0.0:
+  version "2.0.0"
+  resolved "https://registry.yarnpkg.com/shebang-command/-/shebang-command-2.0.0.tgz#ccd0af4f8835fbdc265b82461aaf0c36663f34ea"
+  integrity sha512-kHxr2zZpYtdmrN1qDjrrX/Z1rR1kG8Dx+gkpK1G4eXmvXswmcE1hTWBWYUzlraYw1/yZp6YuDY77YtvbN0dmDA==
+  dependencies:
+    shebang-regex "^3.0.0"
+
 shebang-regex@^1.0.0:
   version "1.0.0"
   resolved "https://registry.yarnpkg.com/shebang-regex/-/shebang-regex-1.0.0.tgz#da42f49740c0b42db2ca9728571cb190c98efea3"
   integrity sha1-2kL0l0DAtC2yypcoVxyxkMmO/qM=
 
+shebang-regex@^3.0.0:
+  version "3.0.0"
+  resolved "https://registry.yarnpkg.com/shebang-regex/-/shebang-regex-3.0.0.tgz#ae16f1644d873ecad843b0307b143362d4c42172"
+  integrity sha512-7++dFhtcx3353uBaq8DDR4NuxBetBzC7ZQOhmTQInHEd6bSrXdiEyzCvG07Z44UYdLShWUyXt5M/yhz8ekcb1A==
+
 shellwords@^0.1.1:
   version "0.1.1"
   resolved "https://registry.yarnpkg.com/shellwords/-/shellwords-0.1.1.tgz#d6b9181c1a48d397324c84871efbcfc73fc0654b"
@@ -5465,6 +5498,13 @@ which@^1.2.9, which@^1.3.0:
   dependencies:
     isexe "^2.0.0"
 
+which@^2.0.1:
+  version "2.0.2"
+  resolved "https://registry.yarnpkg.com/which/-/which-2.0.2.tgz#7c6a8dd0a636a0327e10b59c9286eee93f3f51b1"
+  integrity sha512-BLI3Tl1TW3Pvl70l3yq3Y64i+awpwXqsGBYWkkqMtnbXgrMD+yj7rhW0kuEDxzJaYXGjEW5ogapKNMEKNMjibA==
+  dependencies:
+    isexe "^2.0.0"
+
 wide-align@^1.1.0:
   version "1.1.3"
   resolved "https://registry.yarnpkg.com/wide-align/-/wide-align-1.1.3.tgz#ae074e6bdc0c14a431e804e624549c633b000457"