diff --git a/kmath-core/src/commonMain/kotlin/space/kscience/kmath/nd/BufferAlgebraND.kt b/kmath-core/src/commonMain/kotlin/space/kscience/kmath/nd/BufferAlgebraND.kt
index 1f231ce9f..859edefb8 100644
--- a/kmath-core/src/commonMain/kotlin/space/kscience/kmath/nd/BufferAlgebraND.kt
+++ b/kmath-core/src/commonMain/kotlin/space/kscience/kmath/nd/BufferAlgebraND.kt
@@ -12,7 +12,7 @@ import space.kscience.kmath.operations.*
 import space.kscience.kmath.structures.BufferFactory
 
 public interface BufferAlgebraND<T, out A : Algebra<T>> : AlgebraND<T, A> {
-    public val indexerBuilder: (IntArray) -> ShapeIndex
+    public val indexerBuilder: (IntArray) -> ShapeIndexer
     public val bufferAlgebra: BufferAlgebra<T, A>
     override val elementAlgebra: A get() = bufferAlgebra.elementAlgebra
 
@@ -43,7 +43,7 @@ public interface BufferAlgebraND<T, out A : Algebra<T>> : AlgebraND<T, A> {
         zipInline(left.toBufferND(), right.toBufferND(), transform)
 
     public companion object {
-        public val defaultIndexerBuilder: (IntArray) -> ShapeIndex = DefaultStrides.Companion::invoke
+        public val defaultIndexerBuilder: (IntArray) -> ShapeIndexer = DefaultStrides.Companion::invoke
     }
 }
 
@@ -80,25 +80,25 @@ internal inline fun <T, A : Algebra<T>> BufferAlgebraND<T, A>.zipInline(
 
 public open class BufferedGroupNDOps<T, out A : Group<T>>(
     override val bufferAlgebra: BufferAlgebra<T, A>,
-    override val indexerBuilder: (IntArray) -> ShapeIndex = BufferAlgebraND.defaultIndexerBuilder
+    override val indexerBuilder: (IntArray) -> ShapeIndexer = BufferAlgebraND.defaultIndexerBuilder
 ) : GroupOpsND<T, A>, BufferAlgebraND<T, A> {
     override fun StructureND<T>.unaryMinus(): StructureND<T> = map { -it }
 }
 
 public open class BufferedRingOpsND<T, out A : Ring<T>>(
     bufferAlgebra: BufferAlgebra<T, A>,
-    indexerBuilder: (IntArray) -> ShapeIndex = BufferAlgebraND.defaultIndexerBuilder
+    indexerBuilder: (IntArray) -> ShapeIndexer = BufferAlgebraND.defaultIndexerBuilder
 ) : BufferedGroupNDOps<T, A>(bufferAlgebra, indexerBuilder), RingOpsND<T, A>
 
 public open class BufferedFieldOpsND<T, out A : Field<T>>(
     bufferAlgebra: BufferAlgebra<T, A>,
-    indexerBuilder: (IntArray) -> ShapeIndex = BufferAlgebraND.defaultIndexerBuilder
+    indexerBuilder: (IntArray) -> ShapeIndexer = BufferAlgebraND.defaultIndexerBuilder
 ) : BufferedRingOpsND<T, A>(bufferAlgebra, indexerBuilder), FieldOpsND<T, A> {
 
     public constructor(
         elementAlgebra: A,
         bufferFactory: BufferFactory<T>,
-        indexerBuilder: (IntArray) -> ShapeIndex = BufferAlgebraND.defaultIndexerBuilder
+        indexerBuilder: (IntArray) -> ShapeIndexer = BufferAlgebraND.defaultIndexerBuilder
     ) : this(BufferFieldOps(elementAlgebra, bufferFactory), indexerBuilder)
 
     override fun scale(a: StructureND<T>, value: Double): StructureND<T> = a.map { it * value }
diff --git a/kmath-core/src/commonMain/kotlin/space/kscience/kmath/nd/BufferND.kt b/kmath-core/src/commonMain/kotlin/space/kscience/kmath/nd/BufferND.kt
index c17632101..afa8f8250 100644
--- a/kmath-core/src/commonMain/kotlin/space/kscience/kmath/nd/BufferND.kt
+++ b/kmath-core/src/commonMain/kotlin/space/kscience/kmath/nd/BufferND.kt
@@ -19,7 +19,7 @@ import space.kscience.kmath.structures.MutableBufferFactory
  * @param buffer The underlying buffer.
  */
 public open class BufferND<out T>(
-    public val indexes: ShapeIndex,
+    public val indexes: ShapeIndexer,
     public open val buffer: Buffer<T>,
 ) : StructureND<T> {
 
@@ -58,7 +58,7 @@ public inline fun <T, reified R : Any> StructureND<T>.mapToBuffer(
  * @param buffer The underlying buffer.
  */
 public class MutableBufferND<T>(
-    strides: ShapeIndex,
+    strides: ShapeIndexer,
     override val buffer: MutableBuffer<T>,
 ) : MutableStructureND<T>, BufferND<T>(strides, buffer) {
     override fun set(index: IntArray, value: T) {
diff --git a/kmath-core/src/commonMain/kotlin/space/kscience/kmath/nd/DoubleFieldND.kt b/kmath-core/src/commonMain/kotlin/space/kscience/kmath/nd/DoubleFieldND.kt
index 961f5869a..853ac43b0 100644
--- a/kmath-core/src/commonMain/kotlin/space/kscience/kmath/nd/DoubleFieldND.kt
+++ b/kmath-core/src/commonMain/kotlin/space/kscience/kmath/nd/DoubleFieldND.kt
@@ -13,7 +13,7 @@ import kotlin.contracts.contract
 import kotlin.math.pow
 
 public class DoubleBufferND(
-    indexes: ShapeIndex,
+    indexes: ShapeIndexer,
     override val buffer: DoubleBuffer,
 ) : BufferND<Double>(indexes, buffer)
 
diff --git a/kmath-core/src/commonMain/kotlin/space/kscience/kmath/nd/ShapeIndex.kt b/kmath-core/src/commonMain/kotlin/space/kscience/kmath/nd/ShapeIndexer.kt
similarity index 95%
rename from kmath-core/src/commonMain/kotlin/space/kscience/kmath/nd/ShapeIndex.kt
rename to kmath-core/src/commonMain/kotlin/space/kscience/kmath/nd/ShapeIndexer.kt
index a78bcfa70..1ce6b7519 100644
--- a/kmath-core/src/commonMain/kotlin/space/kscience/kmath/nd/ShapeIndex.kt
+++ b/kmath-core/src/commonMain/kotlin/space/kscience/kmath/nd/ShapeIndexer.kt
@@ -10,7 +10,7 @@ import kotlin.native.concurrent.ThreadLocal
 /**
  * A converter from linear index to multivariate index
  */
-public interface ShapeIndex{
+public interface ShapeIndexer{
     public val shape: Shape
 
     /**
@@ -42,7 +42,7 @@ public interface ShapeIndex{
 /**
  * Linear transformation of indexes
  */
-public abstract class Strides: ShapeIndex {
+public abstract class Strides: ShapeIndexer {
     /**
      * Array strides
      */
diff --git a/kmath-core/src/commonMain/kotlin/space/kscience/kmath/nd/Structure2D.kt b/kmath-core/src/commonMain/kotlin/space/kscience/kmath/nd/Structure2D.kt
index 8d3cc3a3f..e3552c02e 100644
--- a/kmath-core/src/commonMain/kotlin/space/kscience/kmath/nd/Structure2D.kt
+++ b/kmath-core/src/commonMain/kotlin/space/kscience/kmath/nd/Structure2D.kt
@@ -85,7 +85,7 @@ public interface MutableStructure2D<T> : Structure2D<T>, MutableStructureND<T> {
      */
     @PerformancePitfall
     override val rows: List<MutableStructure1D<T>>
-        get() = List(rowNum) { i -> MutableBuffer1DWrapper(MutableListBuffer(colNum) { j -> get(i, j) })}
+        get() = List(rowNum) { i -> MutableBuffer1DWrapper(MutableListBuffer(colNum) { j -> get(i, j) }) }
 
     /**
      * The buffer of columns of this structure. It gets elements from the structure dynamically.
@@ -100,7 +100,7 @@ public interface MutableStructure2D<T> : Structure2D<T>, MutableStructureND<T> {
  */
 @JvmInline
 private value class Structure2DWrapper<out T>(val structure: StructureND<T>) : Structure2D<T> {
-    override val shape: IntArray get() = structure.shape
+    override val shape: Shape get() = structure.shape
 
     override val rowNum: Int get() = shape[0]
     override val colNum: Int get() = shape[1]
@@ -116,9 +116,8 @@ private value class Structure2DWrapper<out T>(val structure: StructureND<T>) : S
 /**
  * A 2D wrapper for a mutable nd-structure
  */
-private class MutableStructure2DWrapper<T>(val structure: MutableStructureND<T>): MutableStructure2D<T>
-{
-    override val shape: IntArray get() = structure.shape
+private class MutableStructure2DWrapper<T>(val structure: MutableStructureND<T>) : MutableStructure2D<T> {
+    override val shape: Shape get() = structure.shape
 
     override val rowNum: Int get() = shape[0]
     override val colNum: Int get() = shape[1]
@@ -129,7 +128,7 @@ private class MutableStructure2DWrapper<T>(val structure: MutableStructureND<T>)
         structure[index] = value
     }
 
-    override operator fun set(i: Int, j: Int, value: T){
+    override operator fun set(i: Int, j: Int, value: T) {
         structure[intArrayOf(i, j)] = value
     }
 
@@ -152,10 +151,11 @@ public fun <T> StructureND<T>.as2D(): Structure2D<T> = this as? Structure2D<T> ?
 /**
  * Represents a [StructureND] as [Structure2D]. Throws runtime error in case of dimension mismatch.
  */
-public fun <T> MutableStructureND<T>.as2D(): MutableStructure2D<T> = this as? MutableStructure2D<T> ?: when (shape.size) {
-    2 -> MutableStructure2DWrapper(this)
-    else -> error("Can't create 2d-structure from ${shape.size}d-structure")
-}
+public fun <T> MutableStructureND<T>.as2D(): MutableStructure2D<T> =
+    this as? MutableStructure2D<T> ?: when (shape.size) {
+        2 -> MutableStructure2DWrapper(this)
+        else -> error("Can't create 2d-structure from ${shape.size}d-structure")
+    }
 
 /**
  * Expose inner [StructureND] if possible
diff --git a/kmath-core/src/commonMain/kotlin/space/kscience/kmath/nd/StructureND.kt b/kmath-core/src/commonMain/kotlin/space/kscience/kmath/nd/StructureND.kt
index 611d2724f..b4e62366a 100644
--- a/kmath-core/src/commonMain/kotlin/space/kscience/kmath/nd/StructureND.kt
+++ b/kmath-core/src/commonMain/kotlin/space/kscience/kmath/nd/StructureND.kt
@@ -33,7 +33,7 @@ public interface StructureND<out T> : Featured<StructureFeature> {
      * The shape of structure i.e., non-empty sequence of non-negative integers that specify sizes of dimensions of
      * this structure.
      */
-    public val shape: IntArray
+    public val shape: Shape
 
     /**
      * The count of dimensions in this structure. It should be equal to size of [shape].
diff --git a/kmath-multik/src/main/kotlin/space/kscience/kmath/multik/MultikTensorAlgebra.kt b/kmath-multik/src/main/kotlin/space/kscience/kmath/multik/MultikTensorAlgebra.kt
index ed5575b93..a89e92c8e 100644
--- a/kmath-multik/src/main/kotlin/space/kscience/kmath/multik/MultikTensorAlgebra.kt
+++ b/kmath-multik/src/main/kotlin/space/kscience/kmath/multik/MultikTensorAlgebra.kt
@@ -15,6 +15,7 @@ import org.jetbrains.kotlinx.multik.api.zeros
 import org.jetbrains.kotlinx.multik.ndarray.data.*
 import org.jetbrains.kotlinx.multik.ndarray.operations.*
 import space.kscience.kmath.misc.PerformancePitfall
+import space.kscience.kmath.nd.Shape
 import space.kscience.kmath.nd.mapInPlace
 import space.kscience.kmath.operations.*
 import space.kscience.kmath.tensors.api.Tensor
@@ -22,7 +23,7 @@ import space.kscience.kmath.tensors.api.TensorAlgebra
 
 @JvmInline
 public value class MultikTensor<T>(public val array: MutableMultiArray<T, DN>) : Tensor<T> {
-    override val shape: IntArray get() = array.shape
+    override val shape: Shape get() = array.shape
 
     override fun get(index: IntArray): T = array[index]