diff --git a/challenges/mainframe/challenge/Gemfile.lock b/challenges/mainframe/challenge/Gemfile.lock
index 5a2f43c..1e96f44 100644
--- a/challenges/mainframe/challenge/Gemfile.lock
+++ b/challenges/mainframe/challenge/Gemfile.lock
@@ -2,10 +2,7 @@ PATH
   remote: .
   specs:
     challenge (0.0.0)
-      base32 (~> 0.3.2)
-      hexhelper (~> 0.0.2)
       optimist (~> 3.0.0)
-      salsa20 (~> 0.1.3)
       sinatra (~> 2.0.5)
       singlogger (~> 0.0.0)
       thin (~> 1.7.2)
@@ -13,29 +10,28 @@ PATH
 GEM
   remote: https://rubygems.org/
   specs:
-    base32 (0.3.2)
     daemons (1.3.1)
     docile (1.1.5)
     eventmachine (1.2.7)
-    hexhelper (0.0.2)
-    json (2.1.0)
-    mustermann (1.0.3)
-    optimist (3.0.0)
+    json (2.3.1)
+    mustermann (1.1.1)
+      ruby2_keywords (~> 0.0.1)
+    optimist (3.0.1)
     power_assert (1.1.3)
-    rack (2.0.6)
-    rack-protection (2.0.5)
+    rack (2.2.3)
+    rack-protection (2.0.8.1)
       rack
     rake (10.5.0)
-    salsa20 (0.1.3)
+    ruby2_keywords (0.0.2)
     simplecov (0.14.1)
       docile (~> 1.1.0)
       json (>= 1.8, < 3)
       simplecov-html (~> 0.10.0)
     simplecov-html (0.10.2)
-    sinatra (2.0.5)
+    sinatra (2.0.8.1)
       mustermann (~> 1.0)
       rack (~> 2.0)
-      rack-protection (= 2.0.5)
+      rack-protection (= 2.0.8.1)
       tilt (~> 2.0)
     singlogger (0.0.1)
     test-unit (3.2.9)
@@ -44,7 +40,7 @@ GEM
       daemons (~> 1.0, >= 1.0.9)
       eventmachine (~> 1.0, >= 1.0.4)
       rack (>= 1, < 3)
-    tilt (2.0.9)
+    tilt (2.0.10)
 
 PLATFORMS
   ruby