diff --git a/Gemfile.lock b/Gemfile.lock
index 3e12f62..1193707 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -22,8 +22,8 @@ GEM
     em-websocket (0.5.2)
       eventmachine (>= 0.12.9)
       http_parser.rb (~> 0.6.0)
-    ethon (0.12.0)
-      ffi (>= 1.3.0)
+    ethon (0.15.0)
+      ffi (>= 1.15.0)
     eventmachine (1.2.7)
     execjs (2.7.0)
     faraday (1.3.0)
@@ -31,7 +31,7 @@ GEM
       multipart-post (>= 1.2, < 3)
       ruby2_keywords
     faraday-net_http (1.0.1)
-    ffi (1.15.0)
+    ffi (1.15.4)
     forwardable-extended (2.6.0)
     gemoji (3.0.1)
     github-pages (214)
@@ -87,10 +87,10 @@ GEM
     html-pipeline (2.14.0)
       activesupport (>= 2)
       nokogiri (>= 1.4)
-    html-proofer (3.18.8)
+    html-proofer (3.19.3)
       addressable (~> 2.3)
       mercenary (~> 0.3)
-      nokogumbo (~> 2.0)
+      nokogiri (~> 1.12)
       parallel (~> 1.3)
       rainbow (~> 3.0)
       typhoeus (~> 1.3)
@@ -223,16 +223,14 @@ GEM
     nokogiri (1.12.5)
       mini_portile2 (~> 2.6.1)
       racc (~> 1.4)
-    nokogumbo (2.0.5)
-      nokogiri (~> 1.8, >= 1.8.4)
     octokit (4.20.0)
       faraday (>= 0.9)
       sawyer (~> 0.8.0, >= 0.5.3)
-    parallel (1.20.1)
+    parallel (1.21.0)
     pathutil (0.16.2)
       forwardable-extended (~> 2.6)
     public_suffix (4.0.6)
-    racc (1.5.2)
+    racc (1.6.0)
     rainbow (3.0.0)
     rb-fsevent (0.10.4)
     rb-inotify (0.10.1)