diff --git a/Gemfile b/Gemfile
index 7a7f64807ef4bf2ae8c2b80efd1726a3e3d43aa2..35f19b90ca20f0547204f1613091dda58278fef5 100644
--- a/Gemfile
+++ b/Gemfile
@@ -81,6 +81,7 @@ gem 'rubycritic', require: false
 
 # docs
 gem 'rdoc'
+gem 'stackprof'
 
 group :development, :test do
   # profiler
diff --git a/Gemfile.lock b/Gemfile.lock
index 5581e23b9f1dd5365b99fcc3dfda6bf81f5982e1..cea3c858ee916e8157c41c1f6daa194ad48e8ca2 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -42,7 +42,7 @@ GEM
       memoizable (~> 0.4.0)
     arel (6.0.3)
     ast (2.1.0)
-    autoprefixer-rails (6.0.2)
+    autoprefixer-rails (6.0.3)
       execjs
       json
     axiom-types (0.1.1)
@@ -137,7 +137,7 @@ GEM
       railties (>= 3.1.0)
       turbolinks
     json (1.8.3)
-    libv8 (3.16.14.7)
+    libv8 (3.16.14.11)
     locastyle (0.0.1)
     loofah (2.0.3)
       nokogiri (>= 1.5.9)
@@ -151,7 +151,7 @@ GEM
       open4 (~> 1.3.4)
       rake
     mini_portile (0.6.2)
-    minitest (5.8.0)
+    minitest (5.8.1)
     multi_json (1.11.2)
     netrc (0.10.3)
     nokogiri (1.6.6.2)
@@ -170,7 +170,7 @@ GEM
       ast (>= 1.1, < 3.0)
     pg (0.18.3)
     procto (0.0.2)
-    puma (2.13.4)
+    puma (2.14.0)
     rack (1.6.4)
     rack-cors (0.4.0)
     rack-mini-profiler (0.9.7)
@@ -210,7 +210,7 @@ GEM
       parser (~> 2.2.0.pre.7)
       rainbow (>= 1.99, < 3.0)
       unparser (~> 0.2.2)
-    ref (1.0.5)
+    ref (2.0.0)
     responders (2.1.0)
       railties (>= 4.2.0, < 5)
     rest-client (1.8.0)
@@ -250,13 +250,14 @@ GEM
     shoulda-matchers (2.8.0)
       activesupport (>= 3.0.0)
     spring (1.4.0)
-    sprockets (3.3.4)
-      rack (~> 1.0)
+    sprockets (3.3.5)
+      rack (> 1, < 3)
     sprockets-rails (2.3.3)
       actionpack (>= 3.0)
       activesupport (>= 3.0)
       sprockets (>= 2.8, < 4.0)
     sqlite3 (1.3.10)
+    stackprof (0.2.7)
     therubyracer (0.12.2)
       libv8 (~> 3.16.14.0)
       ref
@@ -338,6 +339,7 @@ DEPENDENCIES
   shoulda-callback-matchers (~> 1.1.1)
   spring
   sqlite3
+  stackprof
   therubyracer
   turbolinks
   uglifier (>= 1.3.0)