diff --git a/quicklens/src/main/scala-3/com/softwaremill/quicklens/package.scala b/quicklens/src/main/scala-3/com/softwaremill/quicklens/package.scala
index 5fc30cf..f544c3b 100644
--- a/quicklens/src/main/scala-3/com/softwaremill/quicklens/package.scala
+++ b/quicklens/src/main/scala-3/com/softwaremill/quicklens/package.scala
@@ -3,6 +3,7 @@ package com.softwaremill
 import scala.collection.{Factory, SortedMap}
 import scala.annotation.compileTimeOnly
 import com.softwaremill.quicklens.QuicklensMacros._
+import scala.reflect.ClassTag
 
 package object quicklens {
 
@@ -127,27 +128,33 @@ package object quicklens {
   }
 
   trait QuicklensFunctor[F[_]] {
-    def map[A, B](fa: F[A], f: A => B): F[B]
+    def map[A](fa: F[A], f: A => A): F[A]
     def each[A](fa: F[A], f: A => A): F[A] = map(fa, f)
     def eachWhere[A](fa: F[A], f: A => A, cond: A => Boolean): F[A] = map(fa, x => if cond(x) then f(x) else x)
   }
 
   object QuicklensFunctor {
     given [S <: ([V] =>> Seq[V])]: QuicklensFunctor[S] with {
-      def map[A, B](fa: S[A], f: A => B): S[B] = fa.map(f).asInstanceOf[S[B]]
+      def map[A](fa: S[A], f: A => A): S[A] = fa.map(f).asInstanceOf[S[A]]
     }
 
     given QuicklensFunctor[Option] with {
-      def map[A, B](fa: Option[A], f: A => B): Option[B] = fa.map(f)
+      def map[A](fa: Option[A], f: A => A): Option[A] = fa.map(f)
+    }
+
+    given QuicklensFunctor[Array] with {
+      def map[A](fa: Array[A], f: A => A): Array[A] =
+        implicit val aClassTag: ClassTag[A] = fa.elemTag.asInstanceOf[ClassTag[A]]
+        fa.map(f)
     }
 
     given [K, M <: ([V] =>> Map[K, V])]: QuicklensFunctor[M] with {
-      def map[A, B](fa: M[A], f: A => B): M[B] = {
+      def map[A](fa: M[A], f: A => A): M[A] = {
         val mapped = fa.view.mapValues(f)
         (fa match {
           case sfa: SortedMap[K, A] => sfa.sortedMapFactory.from(mapped)(using sfa.ordering)
           case _                    => mapped.to(fa.mapFactory)
-        }).asInstanceOf[M[B]]
+        }).asInstanceOf[M[A]]
       }
     }
   }
@@ -168,6 +175,18 @@ package object quicklens {
         if fa.isDefinedAt(idx) then fa.updated(idx, f(fa(idx))).asInstanceOf[S[A]] else fa
     }
 
+    given QuicklensIndexedFunctor[Array, Int] with {
+      def at[A](fa: Array[A], f: A => A, idx: Int): Array[A] =
+        implicit val aClassTag: ClassTag[A] = fa.elemTag.asInstanceOf[ClassTag[A]]
+        fa.updated(idx, f(fa(idx)))
+      def atOrElse[A](fa: Array[A], f: A => A, idx: Int, default: => A): Array[A] =
+        implicit val aClassTag: ClassTag[A] = fa.elemTag.asInstanceOf[ClassTag[A]]
+        fa.updated(idx, f(fa.applyOrElse(idx, Function.const(default))))
+      def index[A](fa: Array[A], f: A => A, idx: Int): Array[A] =
+        implicit val aClassTag: ClassTag[A] = fa.elemTag.asInstanceOf[ClassTag[A]]
+        if fa.isDefinedAt(idx) then fa.updated(idx, f(fa(idx))) else fa
+    }
+
     given [K, M <: ([V] =>> Map[K, V])]: QuicklensIndexedFunctor[M, K] with {
       def at[A](fa: M[A], f: A => A, idx: K): M[A] =
         fa.updated(idx, f(fa(idx))).asInstanceOf[M[A]]
diff --git a/quicklens/src/test/scala-3/com/softwaremill/quicklens/test/ModifyAllOptimizedTest.scala b/quicklens/src/test/scala-3/com/softwaremill/quicklens/test/ModifyAllOptimizedTest.scala
index 82e4709..406539f 100644
--- a/quicklens/src/test/scala-3/com/softwaremill/quicklens/test/ModifyAllOptimizedTest.scala
+++ b/quicklens/src/test/scala-3/com/softwaremill/quicklens/test/ModifyAllOptimizedTest.scala
@@ -3,6 +3,7 @@ package com.softwaremill.quicklens
 import org.scalatest.flatspec.AnyFlatSpec
 import org.scalatest.BeforeAndAfterEach
 import org.scalatest.matchers.should.Matchers
+import scala.reflect.ClassTag
 
 class ModifyAllOptimizedTest extends AnyFlatSpec with Matchers with BeforeAndAfterEach {
   import ModifyAllOptimizedTest._
@@ -186,7 +187,7 @@ object ModifyAllOptimizedTest {
   }
 
   given QuicklensFunctor[Opt] with {
-    def map[A, B](fa: Opt[A], f: A => B): Opt[B] =
+    def map[A](fa: Opt[A], f: A => A): Opt[A] =
       Opt.eachCount = Opt.eachCount + 1
       fa match {
         case Nada => Nada
diff --git a/quicklens/src/test/scala/com/softwaremill/quicklens/ModifyArrayIndexTest.scala b/quicklens/src/test/scala/com/softwaremill/quicklens/ModifyArrayIndexTest.scala
new file mode 100644
index 0000000..edc59f8
--- /dev/null
+++ b/quicklens/src/test/scala/com/softwaremill/quicklens/ModifyArrayIndexTest.scala
@@ -0,0 +1,27 @@
+package com.softwaremill.quicklens
+
+import com.softwaremill.quicklens.TestData._
+import org.scalatest.flatspec.AnyFlatSpec
+import org.scalatest.matchers.should.Matchers
+
+class ModifyArrayIndexTest extends AnyFlatSpec with Matchers {
+
+  it should "modify a non-nested array with case class item" in {
+    modify(ar1)(_.index(2).a4.a5.name).using(duplicate) should be(l1at2dup)
+    modify(ar1)(_.index(2))
+      .using(a3 => modify(a3)(_.a4.a5.name).using(duplicate)) should be(l1at2dup)
+  }
+
+  it should "modify a nested array using index" in {
+    modify(arar1)(_.index(2).index(1).name).using(duplicate) should be(ll1at2at1dup)
+  }
+
+  it should "modify a nested array using index and each" in {
+    modify(arar1)(_.index(2).each.name).using(duplicate) should be(ll1at2eachdup)
+    modify(arar1)(_.each.index(1).name).using(duplicate) should be(ll1eachat1dup)
+  }
+
+  it should "not modify if given index does not exist" in {
+    modify(ar1)(_.index(10).a4.a5.name).using(duplicate) should be(l1)
+  }
+}
diff --git a/quicklens/src/test/scala/com/softwaremill/quicklens/TestData.scala b/quicklens/src/test/scala/com/softwaremill/quicklens/TestData.scala
index 9ced840..73cfd97 100644
--- a/quicklens/src/test/scala/com/softwaremill/quicklens/TestData.scala
+++ b/quicklens/src/test/scala/com/softwaremill/quicklens/TestData.scala
@@ -70,6 +70,9 @@ object TestData {
   val is1 = l1.toIndexedSeq
   val iss1 = ss1.map(_.toIndexedSeq).toIndexedSeq
 
+  val ar1: Array[A3] = s1.toArray
+  val arar1: Array[Array[A5]] = ss1.map(_.toArray).toArray
+
   case class M2(m3: Map[String, A4])
 
   val m1 = Map("K1" -> A4(A5("d1")), "K2" -> A4(A5("d2")), "K3" -> A4(A5("d3")))