diff --git a/.github/workflows/quality.yml b/.github/workflows/quality.yml
index 9cbb3250..1260ad32 100644
--- a/.github/workflows/quality.yml
+++ b/.github/workflows/quality.yml
@@ -52,7 +52,7 @@ jobs:
           coverage: "none"
           php-version: "7.4" # https://github.com/Roave/BackwardCompatibilityCheck/issues/283
       - name: "Require Roave/BackwardCompatibilityCheck"
-        run: "composer require --no-update --no-interaction --prefer-dist --prefer-stable --dev roave/backward-compatibility-check:dev-allow-dev-deps-to-be-installed"
+        run: "composer require --no-update --no-interaction --prefer-dist --prefer-stable --dev roave/backward-compatibility-check:6.0.x-dev"
       - name: "Composer update with new requirements"
         run: "composer update --no-interaction --prefer-dist --prefer-stable"
       - name: "Check for BC breaks"
diff --git a/CHANGELOG.md b/CHANGELOG.md
index 3b4fc333..c36d2284 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -2,6 +2,28 @@
 
 All notable changes to this project will be documented in this file, in reverse chronological order by release.
 
+## 6.6.0 - TBD
+
+### Added
+
+- Nothing.
+
+### Changed
+
+- [#246](https://github.com/scoutapp/scout-apm-php/pull/246) Updated Core Agent version to 1.4.0
+
+### Deprecated
+
+- Nothing.
+
+### Removed
+
+- Nothing.
+
+### Fixed
+
+- Nothing.
+
 ## 6.5.0 - 2021-10-28
 
 ### Added
diff --git a/src/Config/Source/DefaultSource.php b/src/Config/Source/DefaultSource.php
index dfface30..4144a8a9 100644
--- a/src/Config/Source/DefaultSource.php
+++ b/src/Config/Source/DefaultSource.php
@@ -51,7 +51,7 @@ private function getDefaultConfig(): array
             ConfigKey::CORE_AGENT_DIRECTORY => '/tmp/scout_apm_core',
             ConfigKey::CORE_AGENT_DOWNLOAD_ENABLED => true,
             ConfigKey::CORE_AGENT_LAUNCH_ENABLED => true,
-            ConfigKey::CORE_AGENT_VERSION => 'v1.3.0',
+            ConfigKey::CORE_AGENT_VERSION => 'v1.4.0',
             ConfigKey::CORE_AGENT_DOWNLOAD_URL => 'https://s3-us-west-1.amazonaws.com/scout-public-downloads/apm_core_agent/release',
             ConfigKey::CORE_AGENT_PERMISSIONS => 0777,
             ConfigKey::MONITORING_ENABLED => false,