diff --git a/maubot/management/frontend/src/Home.js b/maubot/management/frontend/src/Home.js
index 53a8466..464294d 100644
--- a/maubot/management/frontend/src/Home.js
+++ b/maubot/management/frontend/src/Home.js
@@ -18,7 +18,7 @@ import React, { Component } from "react"
 class Home extends Component {
     render() {
         return <main>
-
+            Hello, {localStorage.username}
         </main>
     }
 }
diff --git a/maubot/management/frontend/src/Login.js b/maubot/management/frontend/src/Login.js
index 6788168..af95d07 100644
--- a/maubot/management/frontend/src/Login.js
+++ b/maubot/management/frontend/src/Login.js
@@ -14,6 +14,8 @@
 // You should have received a copy of the GNU Affero General Public License
 // along with this program.  If not, see <https://www.gnu.org/licenses/>.
 import React, { Component } from "react"
+import Spinner from "./Spinner"
+import api from "./api"
 
 class Login extends Component {
     constructor(props, context) {
@@ -21,24 +23,38 @@ class Login extends Component {
         this.state = {
             username: "",
             password: "",
+            loading: false,
+            error: "",
         }
     }
 
     inputChanged = event => this.setState({ [event.target.name]: event.target.value })
 
-    login = () => {
-
+    login = async () => {
+        this.setState({ loading: true })
+        const resp = await api.login(this.state.username, this.state.password)
+        if (resp.token) {
+            await this.props.onLogin(resp.token)
+        } else if (resp.error) {
+            this.setState({ error: resp.error, loading: false })
+        } else {
+            this.setState({ error: "Unknown error", loading: false })
+            console.log("Unknown error:", resp)
+        }
     }
 
     render() {
         return <div className="login-wrapper">
-            <div className="login">
-                <h1 className="title">Maubot Manager</h1>
+            <div className={`login ${this.state.error && "errored"}`}>
+                <h1>Maubot Manager</h1>
                 <input type="text" placeholder="Username" value={this.state.username}
                        name="username" onChange={this.inputChanged}/>
                 <input type="password" placeholder="Password" value={this.state.password}
                        name="password" onChange={this.inputChanged}/>
-                <button onClick={this.login}>Log in</button>
+                <button onClick={this.login}>
+                    {this.state.loading ? <Spinner/> : "Log in"}
+                </button>
+                {this.state.error && <div className="error">{this.state.error}</div>}
             </div>
         </div>
     }
diff --git a/maubot/management/frontend/src/Router.js b/maubot/management/frontend/src/MaubotRouter.js
similarity index 61%
rename from maubot/management/frontend/src/Router.js
rename to maubot/management/frontend/src/MaubotRouter.js
index 3eb4faf..891f613 100644
--- a/maubot/management/frontend/src/Router.js
+++ b/maubot/management/frontend/src/MaubotRouter.js
@@ -18,21 +18,52 @@ import { BrowserRouter as Router, Route, Redirect } from "react-router-dom"
 import PrivateRoute from "./PrivateRoute"
 import Home from "./Home"
 import Login from "./Login"
+import Spinner from "./Spinner"
+import api from "./api"
 
 class MaubotRouter extends Component {
     constructor(props) {
         super(props)
         this.state = {
-            authed: localStorage.accessToken !== undefined,
+            pinged: false,
+            authed: false,
         }
     }
 
+    async componentWillMount() {
+        if (localStorage.accessToken) {
+            await this.ping()
+        }
+        this.setState({ pinged: true })
+    }
+
+    async ping() {
+        try {
+            const username = await api.ping()
+            if (username) {
+                localStorage.username = username
+                this.setState({ authed: true })
+            }
+        } catch (err) {
+            console.error(err)
+        }
+    }
+
+    login = async (token) => {
+        localStorage.accessToken = token
+        await this.ping()
+    }
+
     render() {
+        if (!this.state.pinged) {
+            return <Spinner className="maubot-loading"/>
+        }
         return <Router>
             <div className={`maubot-wrapper ${this.state.authed ? "authenticated" : ""}`}>
                 <Route path="/" exact render={() => <Redirect to={{ pathname: "/dashboard" }}/>}/>
                 <PrivateRoute path="/dashboard" component={Home} authed={this.state.authed}/>
-                <Route path="/login" component={Login}/>
+                <PrivateRoute path="/login" render={() => <Login onLogin={this.login}/>}
+                              authed={!this.state.authed} to="/dashboard"/>
             </div>
         </Router>
     }
diff --git a/maubot/management/frontend/src/PrivateRoute.js b/maubot/management/frontend/src/PrivateRoute.js
index 2180e96..745078d 100644
--- a/maubot/management/frontend/src/PrivateRoute.js
+++ b/maubot/management/frontend/src/PrivateRoute.js
@@ -1,15 +1,27 @@
-import React, { Component } from "react"
+// maubot - A plugin-based Matrix bot system.
+// Copyright (C) 2018 Tulir Asokan
+//
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Affero General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU Affero General Public License for more details.
+//
+// You should have received a copy of the GNU Affero General Public License
+// along with this program.  If not, see <https://www.gnu.org/licenses/>.
+import React from "react"
 import { Route, Redirect } from "react-router-dom"
 
-const PrivateRoute = ({ component, authed, ...rest }) => (
+const PrivateRoute = ({ component, render, authed, to = "/login", ...args }) => (
     <Route
-        {...rest}
+        {...args}
         render={(props) => authed === true
-            ? <Component {...props} />
-            : <Redirect to={{
-                pathname: "/login",
-                state: { from: props.location },
-            }}/>}
+            ? (component ? React.createElement(component, props) : render())
+            : <Redirect to={{ pathname: to }}/>}
     />
 )
 
diff --git a/maubot/management/frontend/src/Spinner.js b/maubot/management/frontend/src/Spinner.js
index 4f227d4..77735f5 100644
--- a/maubot/management/frontend/src/Spinner.js
+++ b/maubot/management/frontend/src/Spinner.js
@@ -1,9 +1,11 @@
 import React from "react"
 
-const Spinner = () => (
-    <div className="loader">
+const Spinner = (props) => (
+    <div {...props} className={`spinner ${props["className"] || ""}`}>
         <svg viewBox="25 25 50 50">
             <circle cx="50" cy="50" r="20" fill="none" strokeWidth="2" strokeMiterlimit="10"/>
         </svg>
     </div>
 )
+
+export default Spinner
diff --git a/maubot/management/frontend/src/api.js b/maubot/management/frontend/src/api.js
index 712eb0d..7e1ef7f 100644
--- a/maubot/management/frontend/src/api.js
+++ b/maubot/management/frontend/src/api.js
@@ -16,14 +16,15 @@
 
 const BASE_PATH = "/_matrix/maubot/v1"
 
-export function login(username, password) {
-    return fetch(`${BASE_PATH}/auth/login`, {
+export async function login(username, password) {
+    const resp = await fetch(`${BASE_PATH}/auth/login`, {
         method: "POST",
         body: JSON.stringify({
             username,
             password,
         }),
     })
+    return await resp.json()
 }
 
 function getHeaders(contentType = "application/json") {
@@ -84,3 +85,10 @@ export async function getClient(id) {
     const resp = await fetch(`${BASE_PATH}/client/${id}`, { headers: getHeaders() })
     return await resp.json()
 }
+
+export default {
+    login, ping,
+    getInstances, getInstance,
+    getPlugins, getPlugin,  uploadPlugin,
+    getClients, getClient,
+}
diff --git a/maubot/management/frontend/src/index.js b/maubot/management/frontend/src/index.js
index 9e9203f..cbe10ed 100644
--- a/maubot/management/frontend/src/index.js
+++ b/maubot/management/frontend/src/index.js
@@ -16,6 +16,6 @@
 import React from "react"
 import ReactDOM from "react-dom"
 import "./style/index.sass"
-import App from "./Router"
+import App from "./MaubotRouter"
 
 ReactDOM.render(<App/>, document.getElementById("root"))
diff --git a/maubot/management/frontend/src/style/base/body.sass b/maubot/management/frontend/src/style/base/body.sass
index 01d90e9..462fe8c 100644
--- a/maubot/management/frontend/src/style/base/body.sass
+++ b/maubot/management/frontend/src/style/base/body.sass
@@ -34,6 +34,10 @@ body
     left: 0
     right: 0
 
+.maubot-loading
+    margin-top: 10rem
+    width: 10rem
+
 //.lindeb
     > header
         position: absolute
diff --git a/maubot/management/frontend/src/style/base/elements.sass b/maubot/management/frontend/src/style/base/elements.sass
index 10a183e..48fb045 100644
--- a/maubot/management/frontend/src/style/base/elements.sass
+++ b/maubot/management/frontend/src/style/base/elements.sass
@@ -14,9 +14,11 @@
 // You should have received a copy of the GNU General Public License
 // along with this program.  If not, see <https://www.gnu.org/licenses/>.
 
-=button()
+=button($width: null, $height: null, $padding: .375rem 1rem)
     font-family: $font-stack
-    padding: .375rem 1rem
+    padding: $padding
+    width: $width
+    height: $height
     background-color: $background-color
     border: none
     border-radius: .25rem
@@ -38,7 +40,7 @@
     &:hover
         background-color: $dark-color
 
-button, .button
+.button
     +button
 
     &.main-color
@@ -76,15 +78,17 @@ button, .button
         &:first-of-type:last-of-type
             border-radius: .25rem
 
-input, textarea
+=input($width: null, $height: null, $vertical-padding: .375rem, $horizontal-padding: 1rem, $font-size: 1rem)
     font-family: $font-stack
     border: 1px solid $border-color
     background-color: $background-color
     color: $text-color
+    width: $width
+    height: $height
     box-sizing: border-box
     border-radius: .25rem
-    padding: .375rem 1rem
-    font-size: 1rem
+    padding: $vertical-padding $horizontal-padding
+    font-size: $font-size
     resize: vertical
 
     &:hover, &:focus
@@ -92,4 +96,13 @@ input, textarea
 
     &:focus
         border-width: 2px
-        padding: calc(.375rem - 1px) 1rem
+        padding: calc(#{$vertical-padding} - 1px) calc(#{$horizontal-padding} - 1px)
+
+.input, .textarea
+    +input
+
+=notification($color: $error-color)
+    padding: 1rem
+    border-radius: .25rem
+    border: 2px solid $color
+    background-color: lighten($color, 25%)
diff --git a/maubot/management/frontend/src/style/index.sass b/maubot/management/frontend/src/style/index.sass
index 20d193d..8486157 100644
--- a/maubot/management/frontend/src/style/index.sass
+++ b/maubot/management/frontend/src/style/index.sass
@@ -13,10 +13,10 @@
 //
 // You should have received a copy of the GNU Affero General Public License
 // along with this program.  If not, see <https://www.gnu.org/licenses/>.
+@import lib/spinner
+
 @import base/vars
 @import base/body
 @import base/elements
 
-@import lib/spinner
-
 @import pages/login
diff --git a/maubot/management/frontend/src/style/lib/spinner.sass b/maubot/management/frontend/src/style/lib/spinner.sass
index 3fb4cbc..d164586 100644
--- a/maubot/management/frontend/src/style/lib/spinner.sass
+++ b/maubot/management/frontend/src/style/lib/spinner.sass
@@ -2,14 +2,11 @@ $green: #008744
 $blue: #0057e7
 $red: #d62d20
 $yellow: #ffa700
-$white: #eee
 
-$width: 100px
-
-.loader
+.spinner
     position: relative
     margin: 0 auto
-    width: $width
+    width: 5rem
 
     &:before
         content: ""
@@ -34,6 +31,14 @@ $width: 100px
             animation: dash 1.5s ease-in-out infinite, color 6s ease-in-out infinite
             stroke-linecap: round
 
+=white-spinner()
+    circle
+        stroke: white !important
+
+=thick-spinner($thickness: 5)
+    svg > circle
+        stroke-width: $thickness
+
 @keyframes rotate
     100%
         transform: rotate(360deg)
diff --git a/maubot/management/frontend/src/style/pages/login.sass b/maubot/management/frontend/src/style/pages/login.sass
index f3d04fa..62b0891 100644
--- a/maubot/management/frontend/src/style/pages/login.sass
+++ b/maubot/management/frontend/src/style/pages/login.sass
@@ -21,24 +21,37 @@
 
 .login
     width: 25rem
-    height: 23.5rem
+    height: 23rem
     display: inline-block
     box-sizing: border-box
     background-color: white
     border-radius: .25rem
     margin-top: 3rem
 
-    .title
+    h1
         color: $main-color
         margin: 3rem 0
 
     input, button
-        width: calc(100% - 5rem)
         margin: .5rem 2.5rem
-        padding: 1rem
+        height: 3rem
+        width: 20rem
 
-    input:focus
-        padding: calc(1rem - 1px)
+    input
+        +input
 
     button
+        +button($width: 20rem, $height: 3rem, $padding: 0)
         +main-color-button
+
+        .spinner
+            +white-spinner
+            +thick-spinner
+            width: 2rem
+
+    &.errored
+        height: 26.5rem
+
+        .error
+            +notification($error-color)
+            margin: .5rem 2.5rem