diff --git a/src/index.js b/src/index.js
deleted file mode 100644
index e6c6a2a..0000000
--- a/src/index.js
+++ /dev/null
@@ -1,145 +0,0 @@
-import React, {
-  createContext,
-  useContext,
-  useEffect,
-  useCallback,
-  useReducer,
-} from 'react';
-
-export const AuthContext = createContext();
-
-export function reducer(state, action) {
-  switch (action.type) {
-    case 'loading': {
-      return { ...state, loading: action.payload };
-    }
-    case 'currentUser': {
-      return { ...state, currentUser: action.payload };
-    }
-    default: {
-      return state;
-    }
-  }
-}
-
-export const AuthProvider = ({
-  children,
-  getCurrentUser,
-  beforeLoginUser,
-  afterLoginUser,
-  beforeLogoutUser,
-  afterLogoutUser,
-  renderLoading,
-}) => {
-  const [state, dispatch] = useReducer(reducer, {
-    loading: getCurrentUser ? true : false,
-    currentUser: null,
-  });
-  const { loading, currentUser } = state;
-
-  function setLoading(payload) {
-    dispatch({ type: 'loading', payload });
-  }
-
-  function setCurrentUser(payload) {
-    dispatch({ type: 'currentUser', payload });
-  }
-
-  const loginUser = useCallback(
-    (user) => {
-      return beforeLoginUser(user)
-        .then((user) => {
-          setCurrentUser(user);
-          return user;
-        })
-        .then((user) => afterLoginUser(user));
-    },
-    [beforeLoginUser, afterLoginUser]
-  );
-
-  const logoutUser = useCallback(() => {
-    return beforeLogoutUser(currentUser)
-      .then((user) => {
-        setCurrentUser(null);
-        return user;
-      })
-      .then((user) => afterLogoutUser(user));
-  }, [currentUser, beforeLogoutUser, afterLogoutUser]);
-
-  const refreshUser = useCallback(() => {
-    if (getCurrentUser) {
-      getCurrentUser()
-        .then((user) => {
-          if (user) {
-            return loginUser(user).then(() => {
-              setLoading(false);
-            });
-          } else {
-            setCurrentUser(null);
-            setLoading(false);
-          }
-        })
-        .catch((err) => {
-          console.warn(err);
-          setCurrentUser(null);
-          setLoading(false);
-        });
-    } else {
-      setLoading(false);
-    }
-  }, [getCurrentUser, loginUser]);
-
-  const providerValue = {
-    loading,
-    setLoading,
-    loginUser,
-    logoutUser,
-    refreshUser,
-    currentUser,
-    setCurrentUser,
-  };
-
-  useEffect(() => {
-    refreshUser();
-  }, [refreshUser]);
-
-  if (loading && renderLoading) {
-    return (
-      <AuthContext.Provider value={providerValue}>
-        {React.createElement(renderLoading)}
-      </AuthContext.Provider>
-    );
-  }
-
-  return (
-    <AuthContext.Provider value={providerValue}>
-      {children}
-    </AuthContext.Provider>
-  );
-};
-
-AuthProvider.defaultProps = {
-  beforeLoginUser: (user) => Promise.resolve(user),
-  afterLoginUser: (user) => Promise.resolve(user),
-  beforeLogoutUser: (user) => Promise.resolve(user),
-  afterLogoutUser: (user) => Promise.resolve(user),
-};
-
-export const useAuth = () => {
-  const context = useContext(AuthContext);
-  return context;
-};
-
-export const AuthProtected = ({ renderLoading, renderLogin, children }) => {
-  const { loading, currentUser } = useAuth();
-
-  if (loading) {
-    return renderLoading ? React.createElement(renderLoading) : null;
-  }
-
-  if (!currentUser) {
-    return renderLogin ? React.createElement(renderLogin) : null;
-  }
-
-  return children;
-};
diff --git a/src/index.ts b/src/index.ts
new file mode 100644
index 0000000..352ca4e
--- /dev/null
+++ b/src/index.ts
@@ -0,0 +1,105 @@
+import React, {
+  createContext,
+  useState,
+  useContext,
+  useEffect,
+  useCallback,
+  useReducer
+} from 'react';
+
+type AuthContextValue = {
+  login: (params: any) => Promise<any>;
+  logout: (params: any) => Promise<void | false | string>;
+  getViewer?: () => Promise<any>;
+  [key: string]: any;
+};
+
+export const AuthContext = createContext();
+
+export function useAuth() {
+  const context = useContext(AuthContext);
+  return context;
+}
+
+export function useLogin() {
+  const context = useContext(AuthContext);
+  return context.login;
+}
+
+export function useLogout() {
+  const context = useContext(AuthContext);
+  return context.logout;
+}
+
+export function useViewer() {
+  const context = useContext(AuthContext);
+  return context.viewer;
+}
+
+export function AuthProvider({ children, provider, renderLoading }) {
+  const [{ loading, viewer, error }, setState] = useState({
+    loading: provider.getViewer ? true : false,
+    viewer: null,
+    error: null
+  });
+
+  const setViewer = (viewer) => {
+    setState({ loading: false, viewer, error: null });
+  };
+
+  const refreshViewer = useCallback(() => {
+    if (provider.getViewer) {
+      provider
+        .getViewer()
+        .then((viewer) => {
+          if (viewer) {
+            setState({ loading: false, viewer, error: null });
+          }
+        })
+        .catch((error) => {
+          setState({ loading: false, viewer: null, error });
+        });
+    }
+  }, [provider]);
+
+  useEffect(() => {
+    refreshViewer();
+  }, [refreshViewer]);
+
+  const providerValue = {
+    loading,
+    viewer,
+    setViewer,
+    refreshViewer,
+    login: provider.login,
+    logout: provider.logout
+  };
+
+  if (loading && renderLoading) {
+    return (
+      <AuthContext.Provider value={providerValue}>
+        {React.createElement(renderLoading)}
+      </AuthContext.Provider>
+    );
+  }
+
+  return (
+    <AuthContext.Provider value={providerValue}>
+      {children}
+    </AuthContext.Provider>
+  );
+}
+
+export const AuthProtected = ({ renderLoading, renderLogin, children }) => {
+  const { loading, viewer } = useAuth();
+
+  if (loading) {
+    return renderLoading ? React.createElement(renderLoading) : null;
+  }
+
+  if (!viewer) {
+    return renderLogin ? React.createElement(renderLogin) : null;
+  }
+
+  return children;
+};