diff --git a/api/hosts-api.js b/api/hosts-api.js
index c801813f..7ab1d884 100644
--- a/api/hosts-api.js
+++ b/api/hosts-api.js
@@ -409,13 +409,6 @@ containersAPI.put({
   title: 'Create a container',
 
   handler (request, response) {
-    const { user } = request;
-    if (!user) {
-      response.statusCode = 403; // Forbidden
-      response.json({ error: 'Unauthorized' }, null, 2);
-      return;
-    }
-
     const projectId = request.query.project;
     if (!(projectId in db.get('projects'))) {
       response.statusCode = 404; // Not Found
@@ -423,6 +416,24 @@ containersAPI.put({
       return;
     }
 
+    const { user, session } = request;
+    if (!user) {
+      if (!session) {
+        return;
+      }
+
+      machines.spawnTemporary(session.id, projectId, (error, machine) => {
+        if (error) {
+          response.statusCode = 500; // Internal Server Error
+          response.json({ error: 'Could not create container' }, null, 2);
+        }
+        response.json({
+          container: machine.docker.container
+        }, null, 2);
+      });
+      return;
+    }
+
     machines.spawn(user, projectId, (error, machine) => {
       if (error) {
         log('[fail] could not spawn machine', error);
diff --git a/lib/boot.js b/lib/boot.js
index e13930a7..7db96ed4 100644
--- a/lib/boot.js
+++ b/lib/boot.js
@@ -348,6 +348,10 @@ exports.registerDockerClient = function (next) {
 };
 
 exports.loadTasks = function (callback) {
+  tasks.addType('destroy-temporary', ({ session, container }) => {
+    const machines = require('./machines');
+    machines.destroyTemporary(session, container, log);
+  });
   setInterval(() => {
     tasks.check();
   }, 60000);
diff --git a/lib/machines.js b/lib/machines.js
index 829a786f..eb97a7a2 100644
--- a/lib/machines.js
+++ b/lib/machines.js
@@ -8,6 +8,7 @@ const docker = require('./docker');
 const log = require('./log');
 const metrics = require('./metrics');
 const streams = require('./streams');
+const tasks = require('./tasks');
 
 // Get an existing user machine with the given project and machine ID.
 exports.getMachineById = function (user, projectId, machineId) {
@@ -185,6 +186,56 @@ exports.spawn = function (user, projectId, callback) {
 
   const machine = getOrCreateNewMachine(user, projectId);
 
+  _spawn(machine, project, function (error, machine) {
+    if (error) {
+      callback(error);
+      return;
+    }
+
+    const containerId = machine.docker.container;
+    // Quickly authorize the user's public SSH keys to access this container.
+    deploySSHAuthorizedKeys(user, machine, error => {
+      log('spawn-sshkeys', containerId.slice(0, 16), error || 'success');
+      db.save();
+    });
+
+    // Install all non-empty user configuration files into this container.
+    Object.keys(user.configurations).forEach(file => {
+      if (!user.configurations[file]) {
+        return;
+      }
+      exports.deployConfiguration(user, machine, file).then(() => {
+        log('spawn-config', file, containerId.slice(0, 16), 'success');
+      }).catch(error => {
+        log('spawn-config', file, containerId.slice(0, 16), error);
+      });
+    });
+    callback(null, machine);
+  });
+};
+
+// Instantiate a new temporary machine for a project. (Fast!)
+exports.spawnTemporary = function (sessionId, projectId, callback) {
+  const machine = createNewTemporaryMachine(sessionId, projectId);
+
+  _spawn(machine, getProject(projectId), (error, machine) => {
+    if (error) {
+      callback(error);
+      return;
+    }
+
+    const destroyDate = new Date(Date.now());
+    destroyDate.setHours(destroyDate.getHours() + 8);
+    tasks.add(destroyDate, 'destroy-temporary', {
+      session: sessionId,
+      container: machine.docker.container
+    });
+
+    callback(null, machine);
+  });
+};
+
+function _spawn (machine, project, callback) {
   // Keep track of the last project update this machine will be based on.
   metrics.set(machine, 'updated', project.data.updated);
 
@@ -207,7 +258,7 @@ exports.spawn = function (user, projectId, callback) {
       log('spawn', image, error);
       machine.status = 'start-failed';
       db.save();
-      callback(new Error('Unable to start machine for project: ' + projectId));
+      callback(new Error('Unable to start machine for project: ' + project.id));
       return;
     }
 
@@ -220,27 +271,9 @@ exports.spawn = function (user, projectId, callback) {
     metrics.push(project, 'spawn-time', [ now, now - time ]);
     db.save();
 
-    // Quickly authorize the user's public SSH keys to access this container.
-    deploySSHAuthorizedKeys(user, machine, error => {
-      log('spawn-sshkeys', container.id.slice(0, 16), error || 'success');
-      db.save();
-    });
-
-    // Install all non-empty user configuration files into this container.
-    Object.keys(user.configurations).forEach(file => {
-      if (!user.configurations[file]) {
-        return;
-      }
-      exports.deployConfiguration(user, machine, file).then(() => {
-        log('spawn-config', file, container.id.slice(0, 16), 'success');
-      }).catch(error => {
-        log('spawn-config', file, container.id.slice(0, 16), error);
-      });
-    });
-
     callback(null, machine);
   });
-};
+}
 
 // Destroy a given user machine and recycle its ports.
 exports.destroy = function (user, projectId, machineId, callback) {
@@ -257,7 +290,7 @@ exports.destroy = function (user, projectId, machineId, callback) {
     return;
   }
 
-  const { container: containerId, host } = machine.docker;
+  const containerId = machine.docker.container;
   if (!containerId) {
     // This machine has no associated container, just recycle it as is.
     machine.status = 'new';
@@ -266,12 +299,9 @@ exports.destroy = function (user, projectId, machineId, callback) {
     return;
   }
 
-  log('destroy', containerId.slice(0, 16), 'started');
-  docker.removeContainer({ host, container: containerId }, error => {
+  _destroy(machine, (error) => {
     if (error) {
-      log('destroy', containerId.slice(0, 16), error);
       callback(error);
-      return;
     }
 
     // Recycle the machine's name and ports.
@@ -279,6 +309,45 @@ exports.destroy = function (user, projectId, machineId, callback) {
     machine.docker.container = '';
     db.save();
     callback();
+  });
+};
+
+exports.destroyTemporary = function (sessionId, containerId, callback) {
+  const machines = db.get('temporaryMachines')[sessionId];
+  if (!machines) {
+    callback(new Error('No machines for session ' + sessionId));
+  }
+
+  const machineIndex = machines.findIndex(machine =>
+    machine.docker.container === containerId);
+
+  if (machineIndex === -1) {
+    callback(new Error('Wrong container ID'));
+  }
+
+  _destroy(machines[machineIndex], (error) => {
+    if (error) {
+      callback(error);
+    }
+
+    machines.splice(machineIndex, 1);
+    db.save();
+    callback();
+  });
+};
+
+function _destroy (machine, callback) {
+  const { container: containerId, host } = machine.docker;
+
+  log('destroy', containerId.slice(0, 16), 'started');
+  docker.removeContainer({ host, container: containerId }, error => {
+    if (error) {
+      log('destroy', containerId.slice(0, 16), error);
+      callback(error);
+      return;
+    }
+
+    callback();
 
     if (!machine.docker.image) {
       log('destroy', containerId.slice(0, 16), 'success');
@@ -297,7 +366,7 @@ exports.destroy = function (user, projectId, machineId, callback) {
       db.save();
     });
   });
-};
+}
 
 // Install or overwrite a configuration file in all the user's containers.
 exports.deployConfigurationInAllContainers = function (user, file) {
@@ -445,6 +514,33 @@ function getOrCreateNewMachine (user, projectId) {
   return machine;
 }
 
+function createNewTemporaryMachine (sessionId, projectId) {
+  const project = getProject(projectId);
+  const temporaryMachines = db.get('temporaryMachines');
+  if (!(sessionId in temporaryMachines)) {
+    temporaryMachines[sessionId] = [];
+  }
+
+  const machines = temporaryMachines[sessionId];
+
+  const machine = {
+    properties: {
+      name: project.name + ' #' + machines.length,
+    },
+    status: 'new',
+    docker: {
+      host: '',
+      container: '',
+      ports: {},
+      logs: ''
+    },
+    data: {}
+  };
+  machines.push(machine);
+
+  return machine;
+}
+
 // Get a unique available port starting from 42000.
 function getPort () {
   const ports = db.get('ports');
diff --git a/templates/projects.html b/templates/projects.html
index 4d2f7460..749c3f0d 100644
--- a/templates/projects.html
+++ b/templates/projects.html
@@ -9,11 +9,10 @@ <h4>In just a single click, enter a fully-functional development environment. Ye
           <div class="panel-heading">
             <img class="project-icon" src="{{= project.icon in xmlattr}}" alt="{{= project.name in xmlattr}} Logo">
             <h4 class="project-title">{{= project.name in html}}</h4>
-            <div class="project-actions">{{if user then {{
-              <form action="/api/hosts/{{= project.docker.host in uri}}/containers?project={{= id in id}}" class="ajax-form has-feedback is-submit" data-redirect-after-success="/contributions/" method="put">
+            <div class="project-actions">
+              <form action="/api/hosts/{{= project.docker.host in uri}}/containers?project={{= id in id}}" class="ajax-form has-feedback is-submit" method="put">
                 <button class="btn btn-primary" title="Create a new container for this project" type="submit">New Container</button>
-              </form>}} else {{
-              <a class="btn btn-primary" href="/login">New Container</a>}}}}
+              </form>
             </div>
           </div>
           <div class="panel-body">