diff --git a/Gemfile b/Gemfile
index 1998a6fd9f..ae7b14780b 100644
--- a/Gemfile
+++ b/Gemfile
@@ -15,7 +15,7 @@ gem 'uglifier', '>= 1.3.0'
 
 gem 'gds-api-adapters', '~> 59.5'
 gem 'govuk_ab_testing', '~> 2.4'
-gem 'govuk_app_config', '~> 1.18'
+gem 'govuk_app_config', '~> 1.20'
 gem 'govuk_frontend_toolkit', '~> 8.2.0'
 gem 'govuk_publishing_components', '~> 17.12.1'
 gem 'plek', '~> 3.0'
diff --git a/Gemfile.lock b/Gemfile.lock
index f99a5ba406..95d73f5e71 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -109,12 +109,12 @@ GEM
       rubocop-rspec (~> 1.28)
       scss_lint
     govuk_ab_testing (2.4.1)
-    govuk_app_config (1.19.0)
+    govuk_app_config (1.20.0)
       aws-xray-sdk (~> 0.10.0)
-      logstasher (~> 1.2.2)
-      sentry-raven (~> 2.7.1)
+      logstasher (>= 1.2.2, < 1.4.0)
+      sentry-raven (>= 2.7.1, < 2.10.0)
       statsd-ruby (~> 1.4.0)
-      unicorn (~> 5.4.0)
+      unicorn (>= 5.4, < 5.6)
     govuk_frontend_toolkit (8.2.0)
       railties (>= 3.1.0)
       sass (>= 3.2.0)
@@ -158,7 +158,7 @@ GEM
     link_header (0.0.8)
     log4r (1.1.10)
     logstash-event (1.2.02)
-    logstasher (1.2.2)
+    logstasher (1.3.0)
       activesupport (>= 4.0)
       logstash-event (~> 1.2.0)
       request_store
@@ -303,7 +303,7 @@ GEM
     selenium-webdriver (3.142.3)
       childprocess (>= 0.5, < 2.0)
       rubyzip (~> 1.2, >= 1.2.2)
-    sentry-raven (2.7.4)
+    sentry-raven (2.9.0)
       faraday (>= 0.7.6, < 1.0)
     slimmer (13.1.0)
       activesupport
@@ -332,7 +332,7 @@ GEM
       unf_ext
     unf_ext (0.0.7.6)
     unicode-display_width (1.6.0)
-    unicorn (5.4.1)
+    unicorn (5.5.1)
       kgio (~> 2.6)
       raindrops (~> 0.7)
     webdrivers (4.0.1)
@@ -373,7 +373,7 @@ DEPENDENCIES
   gds-api-adapters (~> 59.5)
   govuk-lint
   govuk_ab_testing (~> 2.4)
-  govuk_app_config (~> 1.18)
+  govuk_app_config (~> 1.20)
   govuk_frontend_toolkit (~> 8.2.0)
   govuk_publishing_components (~> 17.12.1)
   govuk_schemas (~> 3.3)