diff --git a/build.sbt b/build.sbt
index 61eb5f0f..ac1198bb 100644
--- a/build.sbt
+++ b/build.sbt
@@ -2,7 +2,7 @@ import com.typesafe.tools.mima.core._
 
 val Scala213 = "2.13.18"
 val Scala212 = "2.12.21"
-val Scala3 = "3.3.7"
+val Scala3 = "3.3.9"
 
 ThisBuild / tlBaseVersion := "2.8"
 ThisBuild / crossScalaVersions := Seq(Scala213, Scala212, Scala3)
diff --git a/slf4j/src/main/scala/org/typelevel/log4cats/slf4j/internal/Slf4jLoggerInternal.scala b/slf4j/src/main/scala/org/typelevel/log4cats/slf4j/internal/Slf4jLoggerInternal.scala
index fc0f771c..30fe5566 100644
--- a/slf4j/src/main/scala/org/typelevel/log4cats/slf4j/internal/Slf4jLoggerInternal.scala
+++ b/slf4j/src/main/scala/org/typelevel/log4cats/slf4j/internal/Slf4jLoggerInternal.scala
@@ -19,6 +19,7 @@ package org.typelevel.log4cats.slf4j.internal
 import cats.effect.*
 import org.slf4j.{Logger as JLogger, MDC}
 import org.typelevel.log4cats.*
+import org.typelevel.scalaccompat.annotation.unused
 
 private[slf4j] object Slf4jLoggerInternal {
 
@@ -34,7 +35,7 @@ private[slf4j] object Slf4jLoggerInternal {
 
   final class Slf4jLogger[F[_]](
       val logger: JLogger,
-      sync: Sync.Type,
+      @unused sync: Sync.Type,
       defaultCtx: Map[String, String]
   )(implicit
       F: Sync[F]