diff --git a/Gemfile b/Gemfile
index f8620a6..287f08f 100644
--- a/Gemfile
+++ b/Gemfile
@@ -6,7 +6,7 @@ gem "ridley"
 gem "tinyconfig", "~> 0.1"
 gem "oj", platforms: :ruby         # to be used by multijson
 gem "jrjackson", platforms: :jruby # to be used by multijson
-gem "puma"
+gem "puma", ">= 2.12.0"
 gem "rubysl", "~> 2.0", platforms: :rbx
 gem "racc", platforms: :rbx
 gem "deep_merge"
diff --git a/Gemfile.lock b/Gemfile.lock
index e552ee1..f2c9345 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -83,13 +83,12 @@ GEM
       coderay (~> 1.1.0)
       method_source (~> 0.8.1)
       slop (~> 3.4)
-    puma (2.8.2)
-      rack (>= 1.1, < 2.0)
+    puma (3.12.6)
     pygments.rb (0.6.0)
       posix-spawn (~> 0.3.6)
       yajl-ruby (= 1.2.1)
     racc (1.4.11)
-    rack (1.6.0)
+    rack (1.6.13)
     rack-protection (1.5.3)
       rack
     rack-test (0.6.2)
@@ -363,7 +362,7 @@ DEPENDENCIES
   kramdown
   oj
   pry
-  puma
+  puma (>= 2.12.0)
   pygments.rb
   racc
   rack-test
@@ -373,3 +372,6 @@ DEPENDENCIES
   sinatra
   tinyconfig (~> 0.1)
   wrong (= 0.7.1)
+
+BUNDLED WITH
+   2.1.4