diff --git a/Gemfile b/Gemfile
index 99e0a723c..1c04aea44 100644
--- a/Gemfile
+++ b/Gemfile
@@ -72,6 +72,7 @@ group :development, :test do
   gem "knapsack_pro", "~> 1.1.0"
   gem "launchy", "~> 2.4.3"
   gem "letter_opener_web", "~> 1.3.4"
+  gem "puma", "~> 3.12.1"
   gem "spring", "~> 2.0.1"
   gem "spring-commands-rspec", "~> 1.0.4"
 end
diff --git a/Gemfile.lock b/Gemfile.lock
index 164c451de..bef18a154 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -345,6 +345,7 @@ GEM
       arel (>= 6)
     powerpack (0.1.2)
     public_suffix (3.0.3)
+    puma (3.12.1)
     rack (2.0.6)
     rack-accept (0.4.5)
       rack (>= 0.4)
@@ -581,6 +582,7 @@ DEPENDENCIES
   paranoia (~> 2.4.1)
   pg (~> 0.21.0)
   pg_search (~> 2.0.1)
+  puma (~> 3.12.1)
   rails (= 5.0.7.2)
   rails-assets-leaflet!
   rails-assets-markdown-it (~> 8.2.1)!