diff --git a/Gemfile b/Gemfile
index 1903d66e6abf324f02664d9845259ea856898471..924ee382f4d14981141a8b929b4e94a1f6c9163e 100644
--- a/Gemfile
+++ b/Gemfile
@@ -22,7 +22,7 @@ gem "mysql2", '~> 0.3.16', group: :mysql
 gem "pg", '~> 0.18.2', group: :postgres
 
 # Authentication libraries
-gem "devise", '~> 3.2.4'
+gem "devise", '~> 3.5.2'
 gem "devise-async", '~> 0.9.0'
 gem 'omniauth', "~> 1.2.2"
 gem 'omniauth-google-oauth2', '~> 0.2.5'
@@ -38,7 +38,7 @@ gem 'omniauth_crowd'
 gem "rack-oauth2", "~> 1.0.5"
 
 # Two-factor authentication
-gem 'devise-two-factor', '~> 1.0.1'
+gem 'devise-two-factor', '~> 2.0.0'
 gem 'rqrcode-rails3', '~> 0.1.7'
 gem 'attr_encrypted', '~> 1.3.4'
 
diff --git a/Gemfile.lock b/Gemfile.lock
index f43e885ce485ae9e3a1f9c034e8e009ca13f7808..320f7629fb67c9417c56afded1bc30c1acc51d31 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -136,21 +136,21 @@ GEM
       activerecord (>= 3.2.0, < 5.0)
     descendants_tracker (0.0.4)
       thread_safe (~> 0.3, >= 0.3.1)
-    devise (3.2.4)
+    devise (3.5.2)
       bcrypt (~> 3.0)
       orm_adapter (~> 0.1)
       railties (>= 3.2.6, < 5)
+      responders
       thread_safe (~> 0.1)
       warden (~> 1.2.3)
     devise-async (0.9.0)
       devise (~> 3.2)
-    devise-two-factor (1.0.2)
-      activemodel
+    devise-two-factor (2.0.0)
       activesupport
       attr_encrypted (~> 1.3.2)
-      devise (>= 3.2.4, < 3.5)
+      devise (~> 3.5.0)
       railties
-      rotp (< 2)
+      rotp (~> 2)
     diff-lcs (1.2.5)
     diffy (3.0.7)
     docile (1.1.5)
@@ -558,12 +558,14 @@ GEM
     request_store (1.2.0)
     rerun (0.10.0)
       listen (~> 2.7, >= 2.7.3)
+    responders (1.1.2)
+      railties (>= 3.2, < 4.2)
     rest-client (1.8.0)
       http-cookie (>= 1.0.2, < 2.0)
       mime-types (>= 1.16, < 3.0)
       netrc (~> 0.7)
     rinku (1.7.3)
-    rotp (1.6.1)
+    rotp (2.1.1)
     rouge (1.10.1)
     rqrcode (0.7.0)
       chunky_png
@@ -806,9 +808,9 @@ DEPENDENCIES
   d3_rails (~> 3.5.5)
   database_cleaner (~> 1.4.0)
   default_value_for (~> 3.0.0)
-  devise (~> 3.2.4)
+  devise (~> 3.5.2)
   devise-async (~> 0.9.0)
-  devise-two-factor (~> 1.0.1)
+  devise-two-factor (~> 2.0.0)
   diffy (~> 3.0.3)
   doorkeeper (~> 2.1.3)
   dropzonejs-rails (~> 0.7.1)
@@ -928,3 +930,6 @@ DEPENDENCIES
   webmock (~> 1.21.0)
   whenever (~> 0.8.4)
   wikicloth (= 0.8.1)
+
+BUNDLED WITH
+   1.10.6
diff --git a/app/controllers/admin/users_controller.rb b/app/controllers/admin/users_controller.rb
index 6092c79c254caf718632415efb21db76245dba82..a19b1abee272c7eef524610c127d0d87e64bd069 100644
--- a/app/controllers/admin/users_controller.rb
+++ b/app/controllers/admin/users_controller.rb
@@ -56,7 +56,7 @@ class Admin::UsersController < Admin::ApplicationController
   end
 
   def confirm
-    if user.confirm!
+    if user.confirm
       redirect_to :back, notice: "Successfully confirmed"
     else
       redirect_to :back, alert: "Error occurred. User was not confirmed"
diff --git a/app/controllers/profiles/two_factor_auths_controller.rb b/app/controllers/profiles/two_factor_auths_controller.rb
index f9af0871cf1846601a62056bc69d0b96c7159f51..e6b99be37fb7fab9bcf2190321a3df0e446b050f 100644
--- a/app/controllers/profiles/two_factor_auths_controller.rb
+++ b/app/controllers/profiles/two_factor_auths_controller.rb
@@ -9,7 +9,7 @@ class Profiles::TwoFactorAuthsController < Profiles::ApplicationController
   end
 
   def create
-    if current_user.valid_otp?(params[:pin_code])
+    if current_user.validate_and_consume_otp!(params[:pin_code])
       current_user.two_factor_enabled = true
       @codes = current_user.generate_otp_backup_codes!
       current_user.save!
diff --git a/app/controllers/sessions_controller.rb b/app/controllers/sessions_controller.rb
index cfa565cd03efbd3245ab1e951f5e4afdbd380a78..1b60d3e27d0ae170a410d8ab43b9109b5e66695d 100644
--- a/app/controllers/sessions_controller.rb
+++ b/app/controllers/sessions_controller.rb
@@ -99,7 +99,7 @@ class SessionsController < Devise::SessionsController
   end
 
   def valid_otp_attempt?(user)
-    user.valid_otp?(user_params[:otp_attempt]) ||
+    user.validate_and_consume_otp!(user_params[:otp_attempt]) ||
     user.invalidate_otp_backup_code!(user_params[:otp_attempt])
   end
 
diff --git a/db/fixtures/production/001_admin.rb b/db/fixtures/production/001_admin.rb
index 1c8740f6ba9ad847d038a482fce1252d67fcac5a..b0c0b6450f67460620c9c9745417b5ecc854f838 100644
--- a/db/fixtures/production/001_admin.rb
+++ b/db/fixtures/production/001_admin.rb
@@ -19,7 +19,7 @@ admin = User.create(
 admin.projects_limit = 10000
 admin.admin = true
 admin.save!
-admin.confirm!
+admin.confirm
 
 if admin.valid?
 puts %Q[
diff --git a/db/migrate/20150920010715_add_consumed_timestep_to_users.rb b/db/migrate/20150920010715_add_consumed_timestep_to_users.rb
new file mode 100644
index 0000000000000000000000000000000000000000..c8438b3f6aabd9caa9a4921b303323552f64554b
--- /dev/null
+++ b/db/migrate/20150920010715_add_consumed_timestep_to_users.rb
@@ -0,0 +1,5 @@
+class AddConsumedTimestepToUsers < ActiveRecord::Migration
+  def change
+    add_column :users, :consumed_timestep, :integer
+  end
+end
diff --git a/db/schema.rb b/db/schema.rb
index d70c4b58e93b2641aa879b46e6ab340bb1246ab5..b8eb9d26779de3d596b7dc03833ec975adacf275 100644
--- a/db/schema.rb
+++ b/db/schema.rb
@@ -11,7 +11,7 @@
 #
 # It's strongly recommended that you check this file into your version control system.
 
-ActiveRecord::Schema.define(version: 20150918084513) do
+ActiveRecord::Schema.define(version: 20150920010715) do
 
   # These are extensions that must be enabled in order to support this database
   enable_extension "plpgsql"
@@ -749,6 +749,7 @@ ActiveRecord::Schema.define(version: 20150918084513) do
     t.string   "public_email",               default: "",    null: false
     t.integer  "dashboard",                  default: 0
     t.integer  "project_view",               default: 0
+    t.integer  "consumed_timestep"
   end
 
   add_index "users", ["admin"], name: "index_users_on_admin", using: :btree
diff --git a/spec/controllers/profiles/two_factor_auths_controller_spec.rb b/spec/controllers/profiles/two_factor_auths_controller_spec.rb
index f54706e3aa32056c4ebecf66b45408925b6bc03b..4fb1473c2d264ffc651487a2a8217c9d2879c65b 100644
--- a/spec/controllers/profiles/two_factor_auths_controller_spec.rb
+++ b/spec/controllers/profiles/two_factor_auths_controller_spec.rb
@@ -37,7 +37,7 @@ describe Profiles::TwoFactorAuthsController do
 
     context 'with valid pin' do
       before do
-        expect(user).to receive(:valid_otp?).with(pin).and_return(true)
+        expect(user).to receive(:validate_and_consume_otp!).with(pin).and_return(true)
       end
 
       it 'sets two_factor_enabled' do
@@ -63,7 +63,7 @@ describe Profiles::TwoFactorAuthsController do
 
     context 'with invalid pin' do
       before do
-        expect(user).to receive(:valid_otp?).with(pin).and_return(false)
+        expect(user).to receive(:validate_and_consume_otp!).with(pin).and_return(false)
       end
 
       it 'assigns error' do
diff --git a/spec/mailers/notify_spec.rb b/spec/mailers/notify_spec.rb
index 97c07ad7d550ccde80a3584c39a251bd2ed2b167..2c97a521d96217d701af3f6f4f56478e2c038fc4 100644
--- a/spec/mailers/notify_spec.rb
+++ b/spec/mailers/notify_spec.rb
@@ -712,7 +712,7 @@ describe Notify do
 
         before do
           user.update_attribute(:email, "user@company.com")
-          user.confirm!
+          user.confirm
         end
 
         it "is sent from the committer email" do
@@ -730,7 +730,7 @@ describe Notify do
 
         before do
           user.update_attribute(:email, "user@something.company.com")
-          user.confirm!
+          user.confirm
         end
 
         it "is sent from the default email" do
@@ -748,7 +748,7 @@ describe Notify do
 
         before do
           user.update_attribute(:email, "user@mpany.com")
-          user.confirm!
+          user.confirm
         end
 
         it "is sent from the default email" do
diff --git a/spec/models/user_spec.rb b/spec/models/user_spec.rb
index eeb9069aa17d87c10274df00a91ac584d94ddd25..480950859a29391485d424e9d31875077031f32d 100644
--- a/spec/models/user_spec.rb
+++ b/spec/models/user_spec.rb
@@ -188,7 +188,7 @@ describe User do
     end
 
     it 'confirms a user' do
-      user.confirm!
+      user.confirm
       expect(user.confirmed?).to be_truthy
     end
   end