diff --git a/Gemfile.lock b/Gemfile.lock
index 9dac3c6..52e91f0 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -24,6 +24,7 @@ GEM
     concurrent-ruby (1.3.4)
     contracts (0.16.1)
     csv (3.3.0)
+    date (3.4.1)
     dotenv (3.1.4)
     em-websocket (0.5.3)
       eventmachine (>= 0.12.9)
@@ -120,7 +121,8 @@ GEM
       racc
     parslet (2.0.0)
     popper_js (2.11.8)
-    psych (5.2.0)
+    psych (5.2.3)
+      date
       stringio
     public_suffix (6.0.1)
     racc (1.8.1)
@@ -131,7 +133,7 @@ GEM
     rb-fsevent (0.11.2)
     rb-inotify (0.11.1)
       ffi (~> 1.0)
-    rdoc (6.7.0)
+    rdoc (6.11.0)
       psych (>= 4.0.0)
     regexp_parser (2.9.2)
     rexml (3.3.9)