diff --git a/examples/src/benchmarks/kotlin/kscience/kmath/ast/ExpressionsInterpretersBenchmark.kt b/examples/src/benchmarks/kotlin/kscience/kmath/ast/ExpressionsInterpretersBenchmark.kt
index 6acaca84d..c5edcdedf 100644
--- a/examples/src/benchmarks/kotlin/kscience/kmath/ast/ExpressionsInterpretersBenchmark.kt
+++ b/examples/src/benchmarks/kotlin/kscience/kmath/ast/ExpressionsInterpretersBenchmark.kt
@@ -28,7 +28,7 @@ internal class ExpressionsInterpretersBenchmark {
     @Benchmark
     fun mstExpression() {
         val expr = algebra.mstInField {
-            symbol("x") * number(2.0) + number(2.0) / symbol("x") - number(16.0)
+            symbol("x") * 2.0 + 2.0 / symbol("x") - 16.0
         }
 
         invokeAndSum(expr)
@@ -37,7 +37,7 @@ internal class ExpressionsInterpretersBenchmark {
     @Benchmark
     fun asmExpression() {
         val expr = algebra.mstInField {
-            symbol("x") * number(2.0) + number(2.0) / symbol("x") - number(16.0)
+            symbol("x") * 2.0 + 2.0 / symbol("x") - 16.0
         }.compile()
 
         invokeAndSum(expr)
diff --git a/examples/src/benchmarks/kotlin/kscience/kmath/benchmarks/DotBenchmark.kt b/examples/src/benchmarks/kotlin/kscience/kmath/benchmarks/DotBenchmark.kt
index 8823e86db..5c59afaee 100644
--- a/examples/src/benchmarks/kotlin/kscience/kmath/benchmarks/DotBenchmark.kt
+++ b/examples/src/benchmarks/kotlin/kscience/kmath/benchmarks/DotBenchmark.kt
@@ -2,9 +2,8 @@ package kscience.kmath.benchmarks
 
 import kotlinx.benchmark.Benchmark
 import kscience.kmath.commons.linear.CMMatrixContext
-import kscience.kmath.commons.linear.toCM
 import kscience.kmath.ejml.EjmlMatrixContext
-import kscience.kmath.ejml.toEjml
+
 import kscience.kmath.linear.BufferMatrixContext
 import kscience.kmath.linear.RealMatrixContext
 import kscience.kmath.linear.real
@@ -26,11 +25,11 @@ class DotBenchmark {
         val matrix1 = Matrix.real(dim, dim) { i, j -> if (i <= j) random.nextDouble() else 0.0 }
         val matrix2 = Matrix.real(dim, dim) { i, j -> if (i <= j) random.nextDouble() else 0.0 }
 
-        val cmMatrix1 = matrix1.toCM()
-        val cmMatrix2 = matrix2.toCM()
+        val cmMatrix1 = CMMatrixContext { matrix1.toCM() }
+        val cmMatrix2 = CMMatrixContext { matrix2.toCM() }
 
-        val ejmlMatrix1 = matrix1.toEjml()
-        val ejmlMatrix2 = matrix2.toEjml()
+        val ejmlMatrix1 = EjmlMatrixContext { matrix1.toEjml() }
+        val ejmlMatrix2 = EjmlMatrixContext { matrix2.toEjml() }
     }
 
     @Benchmark
@@ -49,22 +48,23 @@ class DotBenchmark {
 
     @Benchmark
     fun ejmlMultiplicationwithConversion() {
-        val ejmlMatrix1 = matrix1.toEjml()
-        val ejmlMatrix2 = matrix2.toEjml()
         EjmlMatrixContext {
+            val ejmlMatrix1 = matrix1.toEjml()
+            val ejmlMatrix2 = matrix2.toEjml()
+
             ejmlMatrix1 dot ejmlMatrix2
         }
     }
 
     @Benchmark
     fun bufferedMultiplication() {
-        BufferMatrixContext(RealField, Buffer.Companion::real).invoke{
+        BufferMatrixContext(RealField, Buffer.Companion::real).invoke {
             matrix1 dot matrix2
         }
     }
 
     @Benchmark
-    fun realMultiplication(){
+    fun realMultiplication() {
         RealMatrixContext {
             matrix1 dot matrix2
         }
diff --git a/examples/src/benchmarks/kotlin/kscience/kmath/benchmarks/LargeNDBenchmark.kt b/examples/src/benchmarks/kotlin/kscience/kmath/benchmarks/LargeNDBenchmark.kt
deleted file mode 100644
index 395fde619..000000000
--- a/examples/src/benchmarks/kotlin/kscience/kmath/benchmarks/LargeNDBenchmark.kt
+++ /dev/null
@@ -1,25 +0,0 @@
-package kscience.kmath.benchmarks
-
-import kscience.kmath.structures.NDField
-import org.openjdk.jmh.annotations.Benchmark
-import org.openjdk.jmh.annotations.Scope
-import org.openjdk.jmh.annotations.State
-import org.openjdk.jmh.infra.Blackhole
-import kotlin.random.Random
-
-@State(Scope.Benchmark)
-class LargeNDBenchmark {
-    val arraySize = 10000
-    val RANDOM = Random(222)
-    val src1 = DoubleArray(arraySize) { RANDOM.nextDouble() }
-    val src2 = DoubleArray(arraySize) { RANDOM.nextDouble() }
-    val field = NDField.real(arraySize)
-    val kmathArray1 = field.produce { (a) -> src1[a] }
-    val kmathArray2 = field.produce { (a) -> src2[a] }
-
-    @Benchmark
-    fun test10000(bh: Blackhole) {
-        bh.consume(field.add(kmathArray1, kmathArray2))
-    }
-
-}
\ No newline at end of file
diff --git a/examples/src/benchmarks/kotlin/kscience/kmath/benchmarks/LinearAlgebraBenchmark.kt b/examples/src/benchmarks/kotlin/kscience/kmath/benchmarks/LinearAlgebraBenchmark.kt
index ec8714617..5ff43ef80 100644
--- a/examples/src/benchmarks/kotlin/kscience/kmath/benchmarks/LinearAlgebraBenchmark.kt
+++ b/examples/src/benchmarks/kotlin/kscience/kmath/benchmarks/LinearAlgebraBenchmark.kt
@@ -5,10 +5,8 @@ import kotlinx.benchmark.Benchmark
 import kscience.kmath.commons.linear.CMMatrixContext
 import kscience.kmath.commons.linear.CMMatrixContext.dot
 import kscience.kmath.commons.linear.inverse
-import kscience.kmath.commons.linear.toCM
 import kscience.kmath.ejml.EjmlMatrixContext
 import kscience.kmath.ejml.inverse
-import kscience.kmath.ejml.toEjml
 import kscience.kmath.operations.invoke
 import kscience.kmath.structures.Matrix
 import org.openjdk.jmh.annotations.Scope
@@ -35,16 +33,14 @@ class LinearAlgebraBenchmark {
     @Benchmark
     fun cmLUPInversion() {
         CMMatrixContext {
-            val cm = matrix.toCM()             //avoid overhead on conversion
-            inverse(cm)
+            inverse(matrix)
         }
     }
 
     @Benchmark
     fun ejmlInverse() {
         EjmlMatrixContext {
-            val km = matrix.toEjml()      //avoid overhead on conversion
-            inverse(km)
+            inverse(matrix)
         }
     }
 }
\ No newline at end of file
diff --git a/kmath-commons/src/main/kotlin/kscience/kmath/commons/linear/CMMatrix.kt b/kmath-commons/src/main/kotlin/kscience/kmath/commons/linear/CMMatrix.kt
index 48b6e0ef1..850446afa 100644
--- a/kmath-commons/src/main/kotlin/kscience/kmath/commons/linear/CMMatrix.kt
+++ b/kmath-commons/src/main/kotlin/kscience/kmath/commons/linear/CMMatrix.kt
@@ -2,8 +2,8 @@ package kscience.kmath.commons.linear
 
 import kscience.kmath.linear.DiagonalFeature
 import kscience.kmath.linear.MatrixContext
-import kscience.kmath.linear.MatrixWrapper
 import kscience.kmath.linear.Point
+import kscience.kmath.linear.origin
 import kscience.kmath.misc.UnstableKMathAPI
 import kscience.kmath.structures.Matrix
 import org.apache.commons.math3.linear.*
@@ -47,9 +47,9 @@ public object CMMatrixContext : MatrixContext<Double, CMMatrix> {
         return CMMatrix(Array2DRowRealMatrix(array))
     }
 
-    public fun Matrix<Double>.toCM(): CMMatrix = when {
-        this is CMMatrix -> this
-        this is MatrixWrapper && matrix is CMMatrix -> matrix as CMMatrix
+    @OptIn(UnstableKMathAPI::class)
+    public fun Matrix<Double>.toCM(): CMMatrix = when (val matrix = origin) {
+        is CMMatrix -> matrix
         else -> {
             //TODO add feature analysis
             val array = Array(rowNum) { i -> DoubleArray(colNum) { j -> get(i, j) } }
diff --git a/kmath-core/src/commonMain/kotlin/kscience/kmath/expressions/FunctionalExpressionAlgebra.kt b/kmath-core/src/commonMain/kotlin/kscience/kmath/expressions/FunctionalExpressionAlgebra.kt
index 880a4e34c..1a3668855 100644
--- a/kmath-core/src/commonMain/kotlin/kscience/kmath/expressions/FunctionalExpressionAlgebra.kt
+++ b/kmath-core/src/commonMain/kotlin/kscience/kmath/expressions/FunctionalExpressionAlgebra.kt
@@ -95,8 +95,9 @@ public open class FunctionalExpressionRing<T, A : Ring<T>>(
         super<FunctionalExpressionSpace>.binaryOperationFunction(operation)
 }
 
-public open class FunctionalExpressionField<T, A : Field<T>>(algebra: A) :
-    FunctionalExpressionRing<T, A>(algebra), Field<Expression<T>> {
+public open class FunctionalExpressionField<T, A : Field<T>>(
+    algebra: A,
+) : FunctionalExpressionRing<T, A>(algebra), Field<Expression<T>> {
     /**
      * Builds an Expression of division an expression by another one.
      */
diff --git a/kmath-core/src/commonMain/kotlin/kscience/kmath/linear/BufferMatrix.kt b/kmath-core/src/commonMain/kotlin/kscience/kmath/linear/BufferMatrix.kt
index 80460baca..a74d948fc 100644
--- a/kmath-core/src/commonMain/kotlin/kscience/kmath/linear/BufferMatrix.kt
+++ b/kmath-core/src/commonMain/kotlin/kscience/kmath/linear/BufferMatrix.kt
@@ -43,7 +43,7 @@ public class BufferMatrix<T : Any>(
         if (this === other) return true
 
         return when (other) {
-            is NDStructure<*> -> NDStructure.equals(this, other)
+            is NDStructure<*> -> NDStructure.contentEquals(this, other)
             else -> false
         }
     }
diff --git a/kmath-core/src/commonMain/kotlin/kscience/kmath/linear/LupDecomposition.kt b/kmath-core/src/commonMain/kotlin/kscience/kmath/linear/LupDecomposition.kt
index f4f998da2..5cf7c8f70 100644
--- a/kmath-core/src/commonMain/kotlin/kscience/kmath/linear/LupDecomposition.kt
+++ b/kmath-core/src/commonMain/kotlin/kscience/kmath/linear/LupDecomposition.kt
@@ -224,6 +224,7 @@ public inline fun <reified T : Comparable<T>, F : Field<T>> GenericMatrixContext
 ): Matrix<T> = solveWithLUP(matrix, one(matrix.rowNum, matrix.colNum), bufferFactory, checkSingular)
 
 
+@OptIn(UnstableKMathAPI::class)
 public fun RealMatrixContext.solveWithLUP(a: Matrix<Double>, b: Matrix<Double>): Matrix<Double> {
     // Use existing decomposition if it is provided by matrix
     val bufferFactory: MutableBufferFactory<Double> = MutableBuffer.Companion::real
diff --git a/kmath-core/src/commonMain/kotlin/kscience/kmath/linear/MatrixWrapper.kt b/kmath-core/src/commonMain/kotlin/kscience/kmath/linear/MatrixWrapper.kt
index bbe9c1195..362db1fe7 100644
--- a/kmath-core/src/commonMain/kotlin/kscience/kmath/linear/MatrixWrapper.kt
+++ b/kmath-core/src/commonMain/kotlin/kscience/kmath/linear/MatrixWrapper.kt
@@ -15,29 +15,37 @@ import kotlin.reflect.safeCast
  *
  * @param T the type of items.
  */
-public class MatrixWrapper<T : Any>(
-    public val matrix: Matrix<T>,
+public class MatrixWrapper<T : Any> internal  constructor(
+    public val origin: Matrix<T>,
     public val features: Set<MatrixFeature>,
-) : Matrix<T> by matrix {
+) : Matrix<T> by origin {
 
     /**
      * Get the first feature matching given class. Does not guarantee that matrix has only one feature matching the criteria
      */
     @UnstableKMathAPI
     override fun <T : Any> getFeature(type: KClass<T>): T? = type.safeCast(features.find { type.isInstance(it) })
+        ?: origin.getFeature(type)
 
-    override fun equals(other: Any?): Boolean = matrix == other
-    override fun hashCode(): Int = matrix.hashCode()
+    override fun equals(other: Any?): Boolean = origin == other
+    override fun hashCode(): Int = origin.hashCode()
     override fun toString(): String {
-        return "MatrixWrapper(matrix=$matrix, features=$features)"
+        return "MatrixWrapper(matrix=$origin, features=$features)"
     }
 }
 
+/**
+ * Return the original matrix. If this is a wrapper, return its origin. If not, this matrix.
+ * Origin does not necessary store all features.
+ */
+@UnstableKMathAPI
+public val <T : Any> Matrix<T>.origin: Matrix<T> get() = (this as? MatrixWrapper)?.origin ?: this
+
 /**
  * Add a single feature to a [Matrix]
  */
 public operator fun <T : Any> Matrix<T>.plus(newFeature: MatrixFeature): MatrixWrapper<T> = if (this is MatrixWrapper) {
-    MatrixWrapper(matrix, features + newFeature)
+    MatrixWrapper(origin, features + newFeature)
 } else {
     MatrixWrapper(this, setOf(newFeature))
 }
@@ -47,7 +55,7 @@ public operator fun <T : Any> Matrix<T>.plus(newFeature: MatrixFeature): MatrixW
  */
 public operator fun <T : Any> Matrix<T>.plus(newFeatures: Collection<MatrixFeature>): MatrixWrapper<T> =
     if (this is MatrixWrapper) {
-        MatrixWrapper(matrix, features + newFeatures)
+        MatrixWrapper(origin, features + newFeatures)
     } else {
         MatrixWrapper(this, newFeatures.toSet())
     }
diff --git a/kmath-core/src/commonMain/kotlin/kscience/kmath/operations/Algebra.kt b/kmath-core/src/commonMain/kotlin/kscience/kmath/operations/Algebra.kt
index 2bafd377e..e7eb2770d 100644
--- a/kmath-core/src/commonMain/kotlin/kscience/kmath/operations/Algebra.kt
+++ b/kmath-core/src/commonMain/kotlin/kscience/kmath/operations/Algebra.kt
@@ -92,7 +92,7 @@ public interface Algebra<T> {
  * Call a block with an [Algebra] as receiver.
  */
 // TODO add contract when KT-32313 is fixed
-public inline operator fun <A : Algebra<*>, R> A.invoke(block: A.() -> R): R = block()
+public inline operator fun <A : Algebra<*>, R> A.invoke(block: A.() -> R): R = run(block)
 
 /**
  * Represents "semispace", i.e. algebraic structure with associative binary operation called "addition" as well as
diff --git a/kmath-core/src/commonMain/kotlin/kscience/kmath/operations/Complex.kt b/kmath-core/src/commonMain/kotlin/kscience/kmath/operations/Complex.kt
index 5695e6696..c6409c015 100644
--- a/kmath-core/src/commonMain/kotlin/kscience/kmath/operations/Complex.kt
+++ b/kmath-core/src/commonMain/kotlin/kscience/kmath/operations/Complex.kt
@@ -3,6 +3,7 @@ package kscience.kmath.operations
 import kscience.kmath.memory.MemoryReader
 import kscience.kmath.memory.MemorySpec
 import kscience.kmath.memory.MemoryWriter
+import kscience.kmath.misc.UnstableKMathAPI
 import kscience.kmath.structures.Buffer
 import kscience.kmath.structures.MemoryBuffer
 import kscience.kmath.structures.MutableBuffer
@@ -41,6 +42,7 @@ private val PI_DIV_2 = Complex(PI / 2, 0)
 /**
  * A field of [Complex].
  */
+@OptIn(UnstableKMathAPI::class)
 public object ComplexField : ExtendedField<Complex>, Norm<Complex, Complex>, RingWithNumbers<Complex> {
     override val zero: Complex = 0.0.toComplex()
     override val one: Complex = 1.0.toComplex()
diff --git a/kmath-core/src/commonMain/kotlin/kscience/kmath/structures/NDStructure.kt b/kmath-core/src/commonMain/kotlin/kscience/kmath/structures/NDStructure.kt
index 64e723581..e7d89ca7e 100644
--- a/kmath-core/src/commonMain/kotlin/kscience/kmath/structures/NDStructure.kt
+++ b/kmath-core/src/commonMain/kotlin/kscience/kmath/structures/NDStructure.kt
@@ -54,7 +54,7 @@ public interface NDStructure<T> {
         /**
          * Indicates whether some [NDStructure] is equal to another one.
          */
-        public fun equals(st1: NDStructure<*>, st2: NDStructure<*>): Boolean {
+        public fun contentEquals(st1: NDStructure<*>, st2: NDStructure<*>): Boolean {
             if (st1 === st2) return true
 
             // fast comparison of buffers if possible
@@ -275,7 +275,7 @@ public abstract class NDBuffer<T> : NDStructure<T> {
     override fun elements(): Sequence<Pair<IntArray, T>> = strides.indices().map { it to this[it] }
 
     override fun equals(other: Any?): Boolean {
-        return NDStructure.equals(this, other as? NDStructure<*> ?: return false)
+        return NDStructure.contentEquals(this, other as? NDStructure<*> ?: return false)
     }
 
     override fun hashCode(): Int {
diff --git a/kmath-core/src/commonMain/kotlin/kscience/kmath/structures/RealNDField.kt b/kmath-core/src/commonMain/kotlin/kscience/kmath/structures/RealNDField.kt
index 3eb1dc4ca..60e6de440 100644
--- a/kmath-core/src/commonMain/kotlin/kscience/kmath/structures/RealNDField.kt
+++ b/kmath-core/src/commonMain/kotlin/kscience/kmath/structures/RealNDField.kt
@@ -11,7 +11,7 @@ public typealias RealNDElement = BufferedNDFieldElement<Double, RealField>
 public class RealNDField(override val shape: IntArray) :
     BufferedNDField<Double, RealField>,
     ExtendedNDField<Double, RealField, NDBuffer<Double>>,
-    RingWithNumbers<NDBuffer<Double>>{
+    RingWithNumbers<NDBuffer<Double>> {
 
     override val strides: Strides = DefaultStrides(shape)
 
@@ -24,35 +24,31 @@ public class RealNDField(override val shape: IntArray) :
         return produce { d }
     }
 
-    private inline fun buildBuffer(size: Int, crossinline initializer: (Int) -> Double): Buffer<Double> =
-        RealBuffer(DoubleArray(size) { initializer(it) })
-
-    /**
-     * Inline transform an NDStructure to
-     */
-    override fun map(
+    @Suppress("OVERRIDE_BY_INLINE")
+    override inline fun map(
         arg: NDBuffer<Double>,
-        transform: RealField.(Double) -> Double
+        transform: RealField.(Double) -> Double,
     ): RealNDElement {
         check(arg)
-        val array = buildBuffer(arg.strides.linearSize) { offset -> RealField.transform(arg.buffer[offset]) }
+        val array = RealBuffer(arg.strides.linearSize) { offset -> RealField.transform(arg.buffer[offset]) }
         return BufferedNDFieldElement(this, array)
     }
 
-    override fun produce(initializer: RealField.(IntArray) -> Double): RealNDElement {
-        val array = buildBuffer(strides.linearSize) { offset -> elementContext.initializer(strides.index(offset)) }
+    @Suppress("OVERRIDE_BY_INLINE")
+    override inline fun produce(initializer: RealField.(IntArray) -> Double): RealNDElement {
+        val array = RealBuffer(strides.linearSize) { offset -> elementContext.initializer(strides.index(offset)) }
         return BufferedNDFieldElement(this, array)
     }
 
-    override fun mapIndexed(
+    @Suppress("OVERRIDE_BY_INLINE")
+    override inline fun mapIndexed(
         arg: NDBuffer<Double>,
-        transform: RealField.(index: IntArray, Double) -> Double
+        transform: RealField.(index: IntArray, Double) -> Double,
     ): RealNDElement {
         check(arg)
-
         return BufferedNDFieldElement(
             this,
-            buildBuffer(arg.strides.linearSize) { offset ->
+            RealBuffer(arg.strides.linearSize) { offset ->
                 elementContext.transform(
                     arg.strides.index(offset),
                     arg.buffer[offset]
@@ -60,16 +56,17 @@ public class RealNDField(override val shape: IntArray) :
             })
     }
 
-    override fun combine(
+    @Suppress("OVERRIDE_BY_INLINE")
+    override inline fun combine(
         a: NDBuffer<Double>,
         b: NDBuffer<Double>,
-        transform: RealField.(Double, Double) -> Double
+        transform: RealField.(Double, Double) -> Double,
     ): RealNDElement {
         check(a, b)
-        return BufferedNDFieldElement(
-            this,
-            buildBuffer(strides.linearSize) { offset -> elementContext.transform(a.buffer[offset], b.buffer[offset]) }
-        )
+        val buffer = RealBuffer(strides.linearSize) { offset ->
+            elementContext.transform(a.buffer[offset], b.buffer[offset])
+        }
+        return BufferedNDFieldElement(this, buffer)
     }
 
     override fun NDBuffer<Double>.toElement(): FieldElement<NDBuffer<Double>, *, out BufferedNDField<Double, RealField>> =
diff --git a/kmath-core/src/commonTest/kotlin/kscience/kmath/linear/MatrixTest.kt b/kmath-core/src/commonTest/kotlin/kscience/kmath/linear/MatrixTest.kt
index 0a582e339..d7755dcb5 100644
--- a/kmath-core/src/commonTest/kotlin/kscience/kmath/linear/MatrixTest.kt
+++ b/kmath-core/src/commonTest/kotlin/kscience/kmath/linear/MatrixTest.kt
@@ -7,6 +7,7 @@ import kscience.kmath.structures.as2D
 import kotlin.test.Test
 import kotlin.test.assertEquals
 
+@Suppress("UNUSED_VARIABLE")
 class MatrixTest {
     @Test
     fun testTranspose() {
diff --git a/kmath-core/src/commonTest/kotlin/kscience/kmath/structures/NumberNDFieldTest.kt b/kmath-core/src/commonTest/kotlin/kscience/kmath/structures/NumberNDFieldTest.kt
index f5e008ef3..22a0d3629 100644
--- a/kmath-core/src/commonTest/kotlin/kscience/kmath/structures/NumberNDFieldTest.kt
+++ b/kmath-core/src/commonTest/kotlin/kscience/kmath/structures/NumberNDFieldTest.kt
@@ -8,6 +8,7 @@ import kotlin.math.pow
 import kotlin.test.Test
 import kotlin.test.assertEquals
 
+@Suppress("UNUSED_VARIABLE")
 class NumberNDFieldTest {
     val array1: RealNDElement = real2D(3, 3) { i, j -> (i + j).toDouble() }
     val array2: RealNDElement = real2D(3, 3) { i, j -> (i - j).toDouble() }
diff --git a/kmath-coroutines/src/jvmMain/kotlin/kscience/kmath/structures/LazyNDStructure.kt b/kmath-coroutines/src/jvmMain/kotlin/kscience/kmath/structures/LazyNDStructure.kt
index bb0d19c23..7aa746797 100644
--- a/kmath-coroutines/src/jvmMain/kotlin/kscience/kmath/structures/LazyNDStructure.kt
+++ b/kmath-coroutines/src/jvmMain/kotlin/kscience/kmath/structures/LazyNDStructure.kt
@@ -24,7 +24,7 @@ public class LazyNDStructure<T>(
     }
 
     public override fun equals(other: Any?): Boolean {
-        return NDStructure.equals(this, other as? NDStructure<*> ?: return false)
+        return NDStructure.contentEquals(this, other as? NDStructure<*> ?: return false)
     }
 
     public override fun hashCode(): Int {
diff --git a/kmath-dimensions/src/commonTest/kotlin/kscience/dimensions/DMatrixContextTest.kt b/kmath-dimensions/src/commonTest/kotlin/kscience/dimensions/DMatrixContextTest.kt
index 5b330fcce..b9193d4dd 100644
--- a/kmath-dimensions/src/commonTest/kotlin/kscience/dimensions/DMatrixContextTest.kt
+++ b/kmath-dimensions/src/commonTest/kotlin/kscience/dimensions/DMatrixContextTest.kt
@@ -6,6 +6,7 @@ import kscience.kmath.dimensions.DMatrixContext
 import kscience.kmath.dimensions.one
 import kotlin.test.Test
 
+@Suppress("UNUSED_VARIABLE")
 internal class DMatrixContextTest {
     @Test
     fun testDimensionSafeMatrix() {
diff --git a/kmath-ejml/src/main/kotlin/kscience/kmath/ejml/EjmlMatrix.kt b/kmath-ejml/src/main/kotlin/kscience/kmath/ejml/EjmlMatrix.kt
index 1c2ded447..82a5399fd 100644
--- a/kmath-ejml/src/main/kotlin/kscience/kmath/ejml/EjmlMatrix.kt
+++ b/kmath-ejml/src/main/kotlin/kscience/kmath/ejml/EjmlMatrix.kt
@@ -3,6 +3,7 @@ package kscience.kmath.ejml
 import kscience.kmath.linear.*
 import kscience.kmath.misc.UnstableKMathAPI
 import kscience.kmath.structures.Matrix
+import kscience.kmath.structures.NDStructure
 import kscience.kmath.structures.RealBuffer
 import org.ejml.dense.row.factory.DecompositionFactory_DDRM
 import org.ejml.simple.SimpleMatrix
@@ -15,7 +16,7 @@ import kotlin.reflect.cast
  * @property origin the underlying [SimpleMatrix].
  * @author Iaroslav Postovalov
  */
-public inline class EjmlMatrix(
+public class EjmlMatrix(
     public val origin: SimpleMatrix,
 ) : Matrix<Double> {
     public override val rowNum: Int get() = origin.numRows()
@@ -49,7 +50,7 @@ public inline class EjmlMatrix(
             override val q: Matrix<Double> by lazy { EjmlMatrix(SimpleMatrix(qr.getQ(null, false))) }
             override val r: Matrix<Double> by lazy { EjmlMatrix(SimpleMatrix(qr.getR(null, false))) }
         }
-        CholeskyDecompositionFeature::class ->         object : CholeskyDecompositionFeature<Double> {
+        CholeskyDecompositionFeature::class -> object : CholeskyDecompositionFeature<Double> {
             override val l: Matrix<Double> by lazy {
                 val cholesky =
                     DecompositionFactory_DDRM.chol(rowNum, true).apply { decompose(origin.ddrm.copy()) }
@@ -57,7 +58,7 @@ public inline class EjmlMatrix(
                 EjmlMatrix(SimpleMatrix(cholesky.getT(null))) + LFeature
             }
         }
-        LupDecompositionFeature::class ->         object : LupDecompositionFeature<Double> {
+        LupDecompositionFeature::class -> object : LupDecompositionFeature<Double> {
             private val lup by lazy {
                 DecompositionFactory_DDRM.lu(origin.numRows(), origin.numCols()).apply { decompose(origin.ddrm.copy()) }
             }
@@ -73,7 +74,17 @@ public inline class EjmlMatrix(
             override val p: Matrix<Double> by lazy { EjmlMatrix(SimpleMatrix(lup.getRowPivot(null))) }
         }
         else -> null
-    }?.let{type.cast(it)}
+    }?.let { type.cast(it) }
 
     public override operator fun get(i: Int, j: Int): Double = origin[i, j]
+
+    override fun equals(other: Any?): Boolean {
+        if (this === other) return true
+        if (other !is Matrix<*>) return false
+        return NDStructure.contentEquals(this, other)
+    }
+
+    override fun hashCode(): Int = origin.hashCode()
+
+
 }
diff --git a/kmath-ejml/src/main/kotlin/kscience/kmath/ejml/EjmlMatrixContext.kt b/kmath-ejml/src/main/kotlin/kscience/kmath/ejml/EjmlMatrixContext.kt
index 7198bbd0d..8184d0110 100644
--- a/kmath-ejml/src/main/kotlin/kscience/kmath/ejml/EjmlMatrixContext.kt
+++ b/kmath-ejml/src/main/kotlin/kscience/kmath/ejml/EjmlMatrixContext.kt
@@ -2,8 +2,8 @@ package kscience.kmath.ejml
 
 import kscience.kmath.linear.InverseMatrixFeature
 import kscience.kmath.linear.MatrixContext
-import kscience.kmath.linear.MatrixWrapper
 import kscience.kmath.linear.Point
+import kscience.kmath.linear.origin
 import kscience.kmath.misc.UnstableKMathAPI
 import kscience.kmath.structures.Matrix
 import kscience.kmath.structures.getFeature
@@ -19,9 +19,9 @@ public object EjmlMatrixContext : MatrixContext<Double, EjmlMatrix> {
     /**
      * Converts this matrix to EJML one.
      */
-    public fun Matrix<Double>.toEjml(): EjmlMatrix = when {
-        this is EjmlMatrix -> this
-        this is MatrixWrapper && matrix is EjmlMatrix -> matrix as EjmlMatrix
+    @OptIn(UnstableKMathAPI::class)
+    public fun Matrix<Double>.toEjml(): EjmlMatrix = when (val matrix = origin) {
+        is EjmlMatrix -> matrix
         else -> produce(rowNum, colNum) { i, j -> get(i, j) }
     }
 
diff --git a/kmath-ejml/src/test/kotlin/kscience/kmath/ejml/EjmlMatrixTest.kt b/kmath-ejml/src/test/kotlin/kscience/kmath/ejml/EjmlMatrixTest.kt
index 30d146779..455b52d9d 100644
--- a/kmath-ejml/src/test/kotlin/kscience/kmath/ejml/EjmlMatrixTest.kt
+++ b/kmath-ejml/src/test/kotlin/kscience/kmath/ejml/EjmlMatrixTest.kt
@@ -4,6 +4,7 @@ import kscience.kmath.linear.DeterminantFeature
 import kscience.kmath.linear.LupDecompositionFeature
 import kscience.kmath.linear.MatrixFeature
 import kscience.kmath.linear.plus
+import kscience.kmath.misc.UnstableKMathAPI
 import kscience.kmath.structures.getFeature
 import org.ejml.dense.row.factory.DecompositionFactory_DDRM
 import org.ejml.simple.SimpleMatrix
@@ -39,6 +40,7 @@ internal class EjmlMatrixTest {
         assertEquals(listOf(m.numRows(), m.numCols()), w.shape.toList())
     }
 
+    @OptIn(UnstableKMathAPI::class)
     @Test
     fun features() {
         val m = randomMatrix
@@ -57,6 +59,7 @@ internal class EjmlMatrixTest {
 
     private object SomeFeature : MatrixFeature {}
 
+    @OptIn(UnstableKMathAPI::class)
     @Test
     fun suggestFeature() {
         assertNotNull((EjmlMatrix(randomMatrix) + SomeFeature).getFeature<SomeFeature>())
diff --git a/kmath-stat/src/jvmTest/kotlin/kscience/kmath/stat/MCScopeTest.kt b/kmath-stat/src/jvmTest/kotlin/kscience/kmath/stat/MCScopeTest.kt
index c2304070f..4e29e6105 100644
--- a/kmath-stat/src/jvmTest/kotlin/kscience/kmath/stat/MCScopeTest.kt
+++ b/kmath-stat/src/jvmTest/kotlin/kscience/kmath/stat/MCScopeTest.kt
@@ -62,6 +62,7 @@ class MCScopeTest {
     }
 
 
+    @OptIn(ObsoleteCoroutinesApi::class)
     fun compareResult(test: ATest) {
         val res1 = runBlocking(Dispatchers.Default) { test() }
         val res2 = runBlocking(newSingleThreadContext("test")) { test() }