diff --git a/src/Log/AnalysableLog.php b/src/Log/AnalysableLog.php
index e990bb0..92ea131 100644
--- a/src/Log/AnalysableLog.php
+++ b/src/Log/AnalysableLog.php
@@ -24,7 +24,7 @@ abstract class AnalysableLog extends Log implements AnalysableLogInterface
      * @param AnalyserInterface|null $analyser
      * @return AnalysisInterface
      */
-    public function analyse(AnalyserInterface $analyser = null): AnalysisInterface
+    public function analyse(?AnalyserInterface $analyser = null): AnalysisInterface
     {
         if ($this->analysis !== null) {
             return $this->analysis;
diff --git a/src/Log/AnalysableLogInterface.php b/src/Log/AnalysableLogInterface.php
index c8ad596..34e9931 100644
--- a/src/Log/AnalysableLogInterface.php
+++ b/src/Log/AnalysableLogInterface.php
@@ -29,5 +29,5 @@ public static function getDefaultAnalyser(): AnalyserInterface;
      * @param AnalyserInterface|null $analyser
      * @return AnalysisInterface
      */
-    public function analyse(AnalyserInterface $analyser = null): AnalysisInterface;
+    public function analyse(?AnalyserInterface $analyser = null): AnalysisInterface;
 }
\ No newline at end of file