diff --git a/.pryrc b/.pryrc
index d158c4a..f79751e 100644
--- a/.pryrc
+++ b/.pryrc
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 Pry.config.editor = 'vim'
 require './config/environment'
 puts "Loading #{App.env}"
diff --git a/Rakefile b/Rakefile
index 99d54cd..358da59 100644
--- a/Rakefile
+++ b/Rakefile
@@ -1,2 +1,3 @@
 # frozen_string_literal: true
+
 Dir.glob('lib/tasks/*.rake').each { |r| import r }
diff --git a/config/app.rb b/config/app.rb
index 121d530..9b87fba 100644
--- a/config/app.rb
+++ b/config/app.rb
@@ -1,4 +1,5 @@
 # frozen_string_literal: true
+
 require 'pathname'
 
 # Encapsulates app configuration
diff --git a/config/environment.rb b/config/environment.rb
index 352574a..578fb8c 100644
--- a/config/environment.rb
+++ b/config/environment.rb
@@ -1,4 +1,5 @@
 # frozen_string_literal: true
+
 require_relative 'app'
 $LOAD_PATH << App.root.join('lib')
 Dir[App.root.join('config/initializers/*.rb')].each { |f| require f }
diff --git a/config/initializers/sequel.rb b/config/initializers/sequel.rb
index f1d8af8..26a2d58 100644
--- a/config/initializers/sequel.rb
+++ b/config/initializers/sequel.rb
@@ -1,4 +1,5 @@
 # frozen_string_literal: true
+
 require 'pg'
 require 'sequel'
 
diff --git a/config/schedule.rb b/config/schedule.rb
index e51ba9e..67731cf 100644
--- a/config/schedule.rb
+++ b/config/schedule.rb
@@ -1,4 +1,5 @@
 # frozen_string_literal: true
+
 job_type :rake, 'cd :path && foreman run bundle exec rake :task --silent :output'
 
 every '*/15 13,14,15,16,17 * * 1-5' do
diff --git a/config/unicorn.rb b/config/unicorn.rb
index 9df511e..bb3101f 100644
--- a/config/unicorn.rb
+++ b/config/unicorn.rb
@@ -1,4 +1,5 @@
 # frozen_string_literal: true
+
 worker_process_count = (ENV['WORKER_PROCESSES'] || 4).to_i
 
 preload_app true
diff --git a/db/migrate/001_create_currencies.rb b/db/migrate/001_create_currencies.rb
index 3d1e311..bdbcc59 100644
--- a/db/migrate/001_create_currencies.rb
+++ b/db/migrate/001_create_currencies.rb
@@ -7,7 +7,7 @@ Sequel.migration do
       String  :iso_code
       Float   :rate
 
-      index [:date, :iso_code], unique: true
+      index %i[date iso_code], unique: true
     end
   end
 end
diff --git a/lib/api.rb b/lib/api.rb
index 9c3d4c1..aec3cbd 100644
--- a/lib/api.rb
+++ b/lib/api.rb
@@ -1,4 +1,5 @@
 # frozen_string_literal: true
+
 require 'oj'
 require 'sinatra'
 require 'rack/cors'
diff --git a/lib/currency.rb b/lib/currency.rb
index f6aae41..dcd5632 100644
--- a/lib/currency.rb
+++ b/lib/currency.rb
@@ -1,4 +1,5 @@
 # frozen_string_literal: true
+
 class Currency < Sequel::Model
   dataset_module do
     def recent
diff --git a/lib/quote.rb b/lib/quote.rb
index d4a8d4d..a0aad94 100644
--- a/lib/quote.rb
+++ b/lib/quote.rb
@@ -1,4 +1,5 @@
 # frozen_string_literal: true
+
 require 'currency'
 
 class Quote
diff --git a/lib/tasks/db.rake b/lib/tasks/db.rake
index 776bc8b..20be55c 100644
--- a/lib/tasks/db.rake
+++ b/lib/tasks/db.rake
@@ -1,4 +1,5 @@
 # frozen_string_literal: true
+
 namespace :db do
   desc 'Create db'
   task :create do
diff --git a/lib/tasks/environment.rake b/lib/tasks/environment.rake
index 8729c19..95c6e48 100644
--- a/lib/tasks/environment.rake
+++ b/lib/tasks/environment.rake
@@ -1,4 +1,5 @@
 # frozen_string_literal: true
+
 task :environment do
   require './config/environment'
 end
diff --git a/lib/tasks/rates.rake b/lib/tasks/rates.rake
index 0cbce1f..554c8d7 100644
--- a/lib/tasks/rates.rake
+++ b/lib/tasks/rates.rake
@@ -1,4 +1,5 @@
 # frozen_string_literal: true
+
 namespace :rates do
   task setup: :environment do
     require 'currency'
diff --git a/lib/tasks/test.rake b/lib/tasks/test.rake
index 2e96839..1e65fae 100644
--- a/lib/tasks/test.rake
+++ b/lib/tasks/test.rake
@@ -1,4 +1,5 @@
 # frozen_string_literal: true
+
 return unless ENV['RACK_ENV'] == 'test'
 
 require 'rake/testtask'
@@ -12,4 +13,4 @@ end
 
 RuboCop::RakeTask.new
 
-task default: %w(db:migrate rates:load test rubocop)
+task default: %w[db:migrate rates:load test rubocop]
diff --git a/spec/api_spec.rb b/spec/api_spec.rb
index 5ed2c59..5c45fde 100644
--- a/spec/api_spec.rb
+++ b/spec/api_spec.rb
@@ -1,4 +1,5 @@
 # frozen_string_literal: true
+
 require_relative 'helper'
 require 'rack/test'
 require 'api'
@@ -32,7 +33,7 @@ describe 'the API' do
 
   it 'filters symbols' do
     get '/latest?symbols=USD'
-    json['rates'].keys.must_equal %w(USD)
+    json['rates'].keys.must_equal %w[USD]
   end
 
   it 'aliases base as from' do
@@ -42,7 +43,7 @@ describe 'the API' do
 
   it 'aliases symbols as to' do
     get '/latest?to=USD'
-    json['rates'].keys.must_equal %w(USD)
+    json['rates'].keys.must_equal %w[USD]
   end
 
   it 'returns historical quotes' do
@@ -57,14 +58,14 @@ describe 'the API' do
   end
 
   it 'returns a cache control header' do
-    %w(/ /latest /2012-11-20).each do |path|
+    %w[/ /latest /2012-11-20].each do |path|
       get path
       headers['Cache-Control'].wont_be_nil
     end
   end
 
   it 'returns a last modified header' do
-    %w(/latest /2012-11-20).each do |path|
+    %w[/latest /2012-11-20].each do |path|
       get path
       headers['Last-Modified'].wont_be_nil
     end
@@ -76,7 +77,7 @@ describe 'the API' do
   end
 
   it 'allows cross-origin requests' do
-    %w(/ /latest /2012-11-20).each do |path|
+    %w[/ /latest /2012-11-20].each do |path|
       header 'Origin', '*'
       get path
       assert headers.key?('Access-Control-Allow-Methods')
@@ -84,7 +85,7 @@ describe 'the API' do
   end
 
   it 'responds to preflight requests' do
-    %w(/ /latest /2012-11-20).each do |path|
+    %w[/ /latest /2012-11-20].each do |path|
       header 'Origin', '*'
       header 'Access-Control-Request-Method', 'GET'
       header 'Access-Control-Request-Headers', 'Content-Type'
diff --git a/spec/currency_spec.rb b/spec/currency_spec.rb
index f6a84f4..88d771c 100644
--- a/spec/currency_spec.rb
+++ b/spec/currency_spec.rb
@@ -1,4 +1,5 @@
 # frozen_string_literal: true
+
 require_relative 'helper'
 require 'currency'
 
diff --git a/spec/edge_cases_spec.rb b/spec/edge_cases_spec.rb
index 57f0513..288ff79 100644
--- a/spec/edge_cases_spec.rb
+++ b/spec/edge_cases_spec.rb
@@ -1,4 +1,5 @@
 # frozen_string_literal: true
+
 require_relative 'helper'
 require 'rack/test'
 require 'api'
diff --git a/spec/helper.rb b/spec/helper.rb
index 40f4cd5..41bb245 100644
--- a/spec/helper.rb
+++ b/spec/helper.rb
@@ -1,4 +1,5 @@
 # frozen_string_literal: true
+
 require './config/environment'
 require 'minitest/autorun'
 require 'minitest/pride'
diff --git a/spec/quote_spec.rb b/spec/quote_spec.rb
index 21b7bf5..110badb 100644
--- a/spec/quote_spec.rb
+++ b/spec/quote_spec.rb
@@ -1,4 +1,5 @@
 # frozen_string_literal: true
+
 require_relative 'helper'
 require 'quote'
 
@@ -27,7 +28,7 @@ describe Quote do
 
     it 'casts to hash' do
       stub_rates do |quote|
-        %i(base date rates).each do |key|
+        %i[base date rates].each do |key|
           quote.to_h.keys.must_include key
         end
       end