diff --git a/Gemfile b/Gemfile
index c10abd72..bb5876fc 100644
--- a/Gemfile
+++ b/Gemfile
@@ -1,3 +1,3 @@
 source 'https://rubygems.org'
 
-gem 'sinatra'
+gem 'sinatra', '>= 2.0.0'
diff --git a/Gemfile.lock b/Gemfile.lock
index 3ee5f240..ddb4d1e8 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -1,20 +1,24 @@
 GEM
   remote: https://rubygems.org/
   specs:
-    rack (1.5.2)
-    rack-protection (1.5.3)
+    mustermann (1.1.1)
+      ruby2_keywords (~> 0.0.1)
+    rack (2.2.3.1)
+    rack-protection (2.2.0)
       rack
-    sinatra (1.4.5)
-      rack (~> 1.4)
-      rack-protection (~> 1.4)
-      tilt (~> 1.3, >= 1.3.4)
-    tilt (1.4.1)
+    ruby2_keywords (0.0.5)
+    sinatra (2.2.0)
+      mustermann (~> 1.0)
+      rack (~> 2.2)
+      rack-protection (= 2.2.0)
+      tilt (~> 2.0)
+    tilt (2.0.10)
 
 PLATFORMS
   ruby
 
 DEPENDENCIES
-  sinatra
+  sinatra (>= 2.0.0)
 
 BUNDLED WITH
-   1.14.6
+   1.17.3