diff --git a/.changeset/wild-hairs-jog.md b/.changeset/wild-hairs-jog.md
new file mode 100644
index 00000000..417a9aea
--- /dev/null
+++ b/.changeset/wild-hairs-jog.md
@@ -0,0 +1,5 @@
+---
+"@wpengine/wp-graphql-content-blocks": patch
+---
+
+chore: update PHPStan ruleset for stricter linting, and address newly-discovered tech debt.
diff --git a/includes/Utilities/DomHelpers.php b/includes/Utilities/DomHelpers.php
index 8eda5e55..8a4c8473 100644
--- a/includes/Utilities/DomHelpers.php
+++ b/includes/Utilities/DomHelpers.php
@@ -25,7 +25,7 @@ final class DOMHelpers {
 	 */
 	public static function parseAttribute( $html, $selector, $attribute, $default_value = null ): ?string {
 		$doc = new Document();
-		$doc->loadHTML( $html );
+		$doc->loadHtml( $html );
 		if ( '*' === $selector ) {
 			$selector = '*[' . $attribute . ']';
 		}
@@ -71,11 +71,11 @@ public static function parseFirstNodeAttribute( $html, $attribute ) {
 	 * @param string $selector The selector to use.
 	 * @param mixed  $default_value The default value to return if the selector is not found.
 	 *
-	 * @return string|null extracted innerHTML of selector
+	 * @return string extracted innerHTML of selector
 	 */
 	public static function parseHTML( $html, $selector, $default_value = null ) {
 		$doc = new Document();
-		$doc->loadHTML( $html );
+		$doc->loadHtml( $html );
 		$node       = $doc->find( $selector );
 		$inner_html = isset( $default_value ) ? $default_value : '';
 
@@ -91,11 +91,11 @@ public static function parseHTML( $html, $selector, $default_value = null ) {
 	 * @param string $html The HTML string to parse.
 	 * @param string $selector The element (selector) to extract.
 	 *
-	 * @return string|null the HTML string of the extracted elements
+	 * @return string the HTML string of the extracted elements
 	 */
 	public static function getElementsFromHTML( $html, $selector ) {
 		$doc = new Document();
-		$doc->loadHTML( $html );
+		$doc->loadHtml( $html );
 		$elements = $doc->find( $selector );
 
 		$output = '';
@@ -118,7 +118,7 @@ public static function getElementsFromHTML( $html, $selector ) {
 	 */
 	public static function parseText( $html, $selector ) {
 		$doc = new Document();
-		$doc->loadHTML( $html );
+		$doc->loadHtml( $html );
 		$nodes = $doc->find( $selector );
 
 		if ( count( $nodes ) === 0 ) {
diff --git a/phpstan.neon.dist b/phpstan.neon.dist
index 18a36ee5..5eacf881 100644
--- a/phpstan.neon.dist
+++ b/phpstan.neon.dist
@@ -3,7 +3,19 @@ includes:
 parameters:
 		level: 8
 		inferPrivatePropertyTypeFromConstructor: true
-		checkMissingIterableValueType: false
+		checkAlwaysTrueCheckTypeFunctionCall: true
+		checkAlwaysTrueInstanceof: true
+		checkAlwaysTrueStrictComparison: true
+		checkExplicitMixedMissingReturn: true
+		checkFunctionNameCase: true
+		checkInternalClassCaseSensitivity: true
+		checkMissingIterableValueType: false # @todo this should be true
+		checkTooWideReturnTypesInProtectedAndPublicMethods: true
+		polluteScopeWithAlwaysIterableForeach: false
+		polluteScopeWithLoopInitialAssignments: false
+		reportAlwaysTrueInLastCondition: true
+		reportStaticMethodSignatures: true
+		reportWrongPhpDocTypeInVarTag: true
 		treatPhpDocTypesAsCertain: false
 		stubFiles:
 			# Simulate added properties
diff --git a/phpstan/constants.php b/phpstan/constants.php
index 743bdefe..b42b6a91 100644
--- a/phpstan/constants.php
+++ b/phpstan/constants.php
@@ -6,6 +6,5 @@
  */
 
 define( 'WPGRAPHQL_CONTENT_BLOCKS_VERSION', '0.2.1' );
-define( 'WPGRAPHQL_CONTENT_BLOCKS_AUTOLOAD', true );
 define( 'WPGRAPHQL_CONTENT_BLOCKS_PLUGIN_FILE', 'wp-graphql-content-blocks.php' );
 define( 'WPGRAPHQL_CONTENT_BLOCKS_MIN_PHP_VERSION', '7.4' );