diff --git a/Gemfile.lock b/Gemfile.lock
index 972b88b4a..58442324b 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -132,9 +132,10 @@ GEM
     globalid (0.5.2)
       activesupport (>= 5.0)
     govuk_ab_testing (2.4.2)
-    govuk_app_config (3.3.0)
+    govuk_app_config (4.0.0)
       logstasher (>= 1.2.2, < 2.2.0)
-      sentry-raven (~> 3.1.1)
+      sentry-rails (~> 4.5.0)
+      sentry-ruby (~> 4.5.0)
       statsd-ruby (~> 1.5.0)
       unicorn (>= 5.4, < 5.9)
     govuk_personalisation (0.6.0)
@@ -329,8 +330,16 @@ GEM
     selenium-webdriver (3.142.7)
       childprocess (>= 0.5, < 4.0)
       rubyzip (>= 1.2.2)
-    sentry-raven (3.1.2)
+    sentry-rails (4.5.2)
+      railties (>= 5.0)
+      sentry-ruby-core (~> 4.5.0)
+    sentry-ruby (4.5.2)
+      concurrent-ruby (~> 1.0, >= 1.0.2)
       faraday (>= 1.0)
+      sentry-ruby-core (= 4.5.2)
+    sentry-ruby-core (4.5.2)
+      concurrent-ruby
+      faraday
     simplecov (0.19.0)
       docile (~> 1.1)
       simplecov-html (~> 0.11)