diff --git a/Gemfile b/Gemfile
index 53b7aaea..9458f1be 100644
--- a/Gemfile
+++ b/Gemfile
@@ -183,6 +183,8 @@ gem 'sprockets-rails'
 # for multiple speakers select on proposal/event forms
 gem 'selectize-rails'
 
+# Pin to solve https://github.com/mperham/connection_pool/issues/212
+gem "connection_pool", "< 3"
 # memcached binary connector
 gem 'dalli'
 
diff --git a/Gemfile.lock b/Gemfile.lock
index d3105767..a9f950fa 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -154,7 +154,7 @@ GEM
       ostruct
     cocoon (1.2.15)
     concurrent-ruby (1.3.6)
-    connection_pool (3.0.2)
+    connection_pool (2.5.5)
     countable-rails (0.0.1)
       railties (>= 3.1)
     crack (0.4.5)
@@ -695,6 +695,7 @@ DEPENDENCIES
   climate_control
   cloudinary
   cocoon
+  connection_pool (< 3)
   countable-rails
   daemons
   dalli