diff --git a/session6/solved/1_build_an_app/Gemfile b/session6/solved/1_build_an_app/Gemfile
index 8ad22693..b3f28cd7 100644
--- a/session6/solved/1_build_an_app/Gemfile
+++ b/session6/solved/1_build_an_app/Gemfile
@@ -1,3 +1,3 @@
 source 'https://rubygems.org'
-gem "sinatra",   "~> 1.4"
+gem "sinatra",   "~> 2.2"
 gem "rack-test", "~> 0.6"
diff --git a/session6/solved/1_build_an_app/Gemfile.lock b/session6/solved/1_build_an_app/Gemfile.lock
index d9c92b2c..bedc8595 100644
--- a/session6/solved/1_build_an_app/Gemfile.lock
+++ b/session6/solved/1_build_an_app/Gemfile.lock
@@ -1,20 +1,24 @@
 GEM
   remote: https://rubygems.org/
   specs:
-    rack (1.6.12)
-    rack-protection (1.5.5)
+    mustermann (2.0.2)
+      ruby2_keywords (~> 0.0.1)
+    rack (2.2.4)
+    rack-protection (2.2.3)
       rack
     rack-test (0.6.0)
       rack (>= 1.0)
-    sinatra (1.4.8)
-      rack (~> 1.5)
-      rack-protection (~> 1.4)
-      tilt (>= 1.3, < 3)
-    tilt (2.0.10)
+    ruby2_keywords (0.0.5)
+    sinatra (2.2.3)
+      mustermann (~> 2.0)
+      rack (~> 2.2)
+      rack-protection (= 2.2.3)
+      tilt (~> 2.0)
+    tilt (2.0.11)
 
 PLATFORMS
   ruby
 
 DEPENDENCIES
   rack-test (~> 0.6)
-  sinatra (~> 1.4)
+  sinatra (~> 2.2)