diff --git a/Gemfile.lock b/Gemfile.lock
index 7f41c1e..54db991 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -4,14 +4,12 @@ GEM
     addressable (2.5.2)
       public_suffix (>= 2.0.2, < 4.0)
     colorator (1.1.0)
-    concurrent-ruby (1.0.5)
+    concurrent-ruby (1.3.7)
     em-websocket (0.5.1)
       eventmachine (>= 0.12.9)
       http_parser.rb (~> 0.6.0)
     eventmachine (1.2.5)
-    eventmachine (1.2.5-x64-mingw32)
     ffi (1.9.23)
-    ffi (1.9.23-x64-mingw32)
     forwardable-extended (2.6.0)
     http_parser.rb (0.6.0)
     i18n (0.9.5)
@@ -67,18 +65,16 @@ GEM
       thread_safe (~> 0.1)
     tzinfo-data (1.2018.3)
       tzinfo (>= 1.0.0)
-    wdm (0.1.1)
 
 PLATFORMS
   ruby
-  x64-mingw32
+  x64-mingw-ucrt
 
 DEPENDENCIES
   jekyll (~> 3.7.3)
   jekyll-feed (~> 0.6)
   minima (~> 2.0)
   tzinfo-data
-  wdm (~> 0.1.0)
 
 BUNDLED WITH
    2.1.4