diff --git a/Gemfile b/Gemfile
index 47c4a3d..61cf3b3 100644
--- a/Gemfile
+++ b/Gemfile
@@ -31,3 +31,5 @@ gem "wdm", "~> 0.1.1", :platforms => [:mingw, :x64_mingw, :mswin]
 # Lock `http_parser.rb` gem to `v0.6.x` on JRuby builds since newer versions of the gem
 # do not have a Java counterpart.
 gem "http_parser.rb", "~> 0.6.0", :platforms => [:jruby]
+
+gem "webrick", "~> 1.8"
diff --git a/Gemfile.lock b/Gemfile.lock
index 9e29db7..85d827f 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -269,6 +269,7 @@ GEM
     unf_ext (0.0.9.1)
     unicode-display_width (1.8.0)
     uri (0.13.0)
+    webrick (1.8.1)
 
 PLATFORMS
   aarch64-linux
@@ -286,6 +287,7 @@ DEPENDENCIES
   tzinfo (>= 1, < 3)
   tzinfo-data
   wdm (~> 0.1.1)
+  webrick (~> 1.8)
 
 BUNDLED WITH
    2.5.10