diff --git a/doc/site/Gemfile.lock b/doc/site/Gemfile.lock
index 20da97b..d88f00c 100644
--- a/doc/site/Gemfile.lock
+++ b/doc/site/Gemfile.lock
@@ -21,9 +21,11 @@ GEM
     kramdown (0.13.6)
     linecache (0.46)
       rbx-require-relative (> 0.0.4)
+    mini_portile2 (2.4.0)
     nanoc (3.4.0)
       cri (~> 2.2)
-    nokogiri (1.5.2)
+    nokogiri (1.10.8)
+      mini_portile2 (~> 2.4.0)
     oj (1.3.2)
     pygments.rb (0.2.13)
       rubypython (~> 0.5.3)