diff --git a/lib/authProviders.js b/lib/authProviders.js
index 21601b1..48caf9a 100644
--- a/lib/authProviders.js
+++ b/lib/authProviders.js
@@ -1,7 +1,6 @@
 import invariant from 'invariant';
-import {Type, String} from 'valib';
 
-const notEmpty = (str) => Type.isString(str) && !String.isEmpty(str) || 'cannot be empty';
+const notEmpty = (str) => typeof str === 'string' && str !== '' || 'cannot be empty';
 
 const isValid = (prop, str, validations=[]) => {
   return validations
diff --git a/package-lock.json b/package-lock.json
index b3af007..4606448 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -791,11 +791,6 @@
       "resolved": "https://registry.npmjs.org/to-fast-properties/-/to-fast-properties-1.0.3.tgz",
       "integrity": "sha1-uDVx+k2MJbguIxsG46MFXeTKGkc=",
       "dev": true
-    },
-    "valib": {
-      "version": "2.0.0",
-      "resolved": "https://registry.npmjs.org/valib/-/valib-2.0.0.tgz",
-      "integrity": "sha1-4NRVsQ4XrmBcDzOXGtrHNWTuGKc="
     }
   }
 }
diff --git a/package.json b/package.json
index 453f8c4..6ad307a 100644
--- a/package.json
+++ b/package.json
@@ -43,8 +43,7 @@
     }
   },
   "dependencies": {
-    "invariant": "^2.2.1",
-    "valib": "^2.0.0"
+    "invariant": "^2.2.1"
   },
   "devDependencies": {
     "babel-plugin-transform-async-to-generator": "^6.24.1",