diff --git a/src/main/kotlin/com/github/insanusmokrassar/PsychomatrixBase/Example.kt b/src/main/kotlin/com/github/insanusmokrassar/PsychomatrixBase/Example.kt
index 0164f2e..6105437 100644
--- a/src/main/kotlin/com/github/insanusmokrassar/PsychomatrixBase/Example.kt
+++ b/src/main/kotlin/com/github/insanusmokrassar/PsychomatrixBase/Example.kt
@@ -1,13 +1,4 @@
 package com.github.insanusmokrassar.PsychomatrixBase
 
-import com.github.insanusmokrassar.PsychomatrixBase.domain.entities.MutablePsychomatrix
-import com.github.insanusmokrassar.PsychomatrixBase.domain.entities.operations.TwoGrowFour
-import kotlinx.coroutines.experimental.runBlocking
-import org.joda.time.DateTime
-
 fun main(args: Array<String>) {
-    val psychomatrix = MutablePsychomatrix(DateTime.now().withDate(2022, 12, 22))
-    runBlocking {
-        println(psychomatrix.availableOperations.await())
-    }
 }
diff --git a/src/main/kotlin/com/github/insanusmokrassar/PsychomatrixBase/domain/UseCases/ModifyPsychomatrixUseCase.kt b/src/main/kotlin/com/github/insanusmokrassar/PsychomatrixBase/domain/UseCases/ModifyPsychomatrixUseCase.kt
index 89e70f2..72f0d08 100644
--- a/src/main/kotlin/com/github/insanusmokrassar/PsychomatrixBase/domain/UseCases/ModifyPsychomatrixUseCase.kt
+++ b/src/main/kotlin/com/github/insanusmokrassar/PsychomatrixBase/domain/UseCases/ModifyPsychomatrixUseCase.kt
@@ -1,31 +1,23 @@
 package com.github.insanusmokrassar.PsychomatrixBase.domain.UseCases
 
+import com.github.insanusmokrassar.PsychomatrixBase.domain.entities.MutablePsychomatrix
 import com.github.insanusmokrassar.PsychomatrixBase.domain.entities.Psychomatrix
 import com.github.insanusmokrassar.PsychomatrixBase.domain.entities.operations.Operation
 import kotlinx.coroutines.experimental.Deferred
 import kotlinx.coroutines.experimental.async
 import kotlinx.coroutines.experimental.channels.ReceiveChannel
 
-typealias PsychomatrixOperationIsConvert = Pair<Psychomatrix, Pair<Operation, Boolean>>
+typealias PsychomatrixOperationIsConvert = Pair<MutablePsychomatrix, Pair<Operation, Boolean>>
 
 interface ModifyPsychomatrixUseCase {
 
     fun openPsychomatrixChangedSubscription(): ReceiveChannel<PsychomatrixOperationIsConvert>
 
-    suspend fun makeConvert(psychomatrix: Psychomatrix, operation: Operation): Deferred<Boolean>
-    suspend fun makeInvert(psychomatrix: Psychomatrix, operation: Operation): Deferred<Boolean>
+    suspend fun makeConvert(psychomatrix: MutablePsychomatrix, operation: Operation): Deferred<Boolean>
+    suspend fun makeInvert(psychomatrix: MutablePsychomatrix, operation: Operation): Deferred<Boolean>
 
     suspend fun getConverts(psychomatrix: Psychomatrix): Deferred<List<Operation>>
     suspend fun getInverts(psychomatrix: Psychomatrix): Deferred<List<Operation>>
 
-    suspend fun getOperations(psychomatrix: Psychomatrix): Deferred<List<Operation>> = async {
-        listOf(
-            getConverts(psychomatrix),
-            getInverts(psychomatrix)
-        ).flatMap {
-            it.await()
-        }
-    }
-
     suspend fun getPsychomatrixHistory(psychomatrix: Psychomatrix): Deferred<List<Operation>>
 }
\ No newline at end of file
diff --git a/src/main/kotlin/com/github/insanusmokrassar/PsychomatrixBase/domain/entities/Psychomatrix.kt b/src/main/kotlin/com/github/insanusmokrassar/PsychomatrixBase/domain/entities/Psychomatrix.kt
index 0093c4e..f88c2ad 100644
--- a/src/main/kotlin/com/github/insanusmokrassar/PsychomatrixBase/domain/entities/Psychomatrix.kt
+++ b/src/main/kotlin/com/github/insanusmokrassar/PsychomatrixBase/domain/entities/Psychomatrix.kt
@@ -186,8 +186,4 @@ open class Psychomatrix(val date: DateTime) {
                         getDownDiagSum()
                 )
     }
-
-    override fun equals(other: Any?): Boolean {
-        return super.equals(other) || (other as? Psychomatrix) ?.date == date
-    }
 }
diff --git a/src/main/kotlin/com/github/insanusmokrassar/PsychomatrixBase/domain/interactors/ModifyPsychomatrixUseCaseInteractor.kt b/src/main/kotlin/com/github/insanusmokrassar/PsychomatrixBase/domain/interactors/ModifyPsychomatrixUseCaseInteractor.kt
index f16e7ba..2432126 100644
--- a/src/main/kotlin/com/github/insanusmokrassar/PsychomatrixBase/domain/interactors/ModifyPsychomatrixUseCaseInteractor.kt
+++ b/src/main/kotlin/com/github/insanusmokrassar/PsychomatrixBase/domain/interactors/ModifyPsychomatrixUseCaseInteractor.kt
@@ -20,13 +20,13 @@ class ModifyPsychomatrixUseCaseInteractor : ModifyPsychomatrixUseCase {
         return psychomatrixChangedBroadcastChannel.openSubscription()
     }
 
-    override suspend fun makeConvert(psychomatrix: Psychomatrix, operation: Operation): Deferred<Boolean> {
+    override suspend fun makeConvert(psychomatrix: MutablePsychomatrix, operation: Operation): Deferred<Boolean> {
         return async {
             asMutablePsychomatrix(psychomatrix).applyConvert(operation)
         }
     }
 
-    override suspend fun makeInvert(psychomatrix: Psychomatrix, operation: Operation): Deferred<Boolean> {
+    override suspend fun makeInvert(psychomatrix: MutablePsychomatrix, operation: Operation): Deferred<Boolean> {
         return async {
             asMutablePsychomatrix(psychomatrix).applyInvert(operation)
         }
diff --git a/src/main/kotlin/com/github/insanusmokrassar/PsychomatrixBase/presentation/presenters/DefaultRealisations/ModifyPsychomatrixPresenterImpl.kt b/src/main/kotlin/com/github/insanusmokrassar/PsychomatrixBase/presentation/presenters/DefaultRealisations/ModifyPsychomatrixPresenterImpl.kt
index 703a84e..596445f 100644
--- a/src/main/kotlin/com/github/insanusmokrassar/PsychomatrixBase/presentation/presenters/DefaultRealisations/ModifyPsychomatrixPresenterImpl.kt
+++ b/src/main/kotlin/com/github/insanusmokrassar/PsychomatrixBase/presentation/presenters/DefaultRealisations/ModifyPsychomatrixPresenterImpl.kt
@@ -2,6 +2,7 @@ package com.github.insanusmokrassar.PsychomatrixBase.presentation.presenters.Def
 
 import com.github.insanusmokrassar.PsychomatrixBase.domain.UseCases.ModifyPsychomatrixUseCase
 import com.github.insanusmokrassar.PsychomatrixBase.domain.UseCases.PsychomatrixOperationIsConvert
+import com.github.insanusmokrassar.PsychomatrixBase.domain.entities.MutablePsychomatrix
 import com.github.insanusmokrassar.PsychomatrixBase.domain.entities.Psychomatrix
 import com.github.insanusmokrassar.PsychomatrixBase.domain.entities.operations.*
 import com.github.insanusmokrassar.PsychomatrixBase.presentation.presenters.ModifyPsychomatrixPresenter
@@ -17,7 +18,7 @@ class ModifyPsychomatrixPresenterImpl(
 ) : ModifyPsychomatrixPresenter {
 
     private val availableConverts = HashMap<Psychomatrix, List<Operation>>()
-    private val availableInverts = HashMap<Psychomatrix, List<Operation>>()
+    private val availableInverts = HashMap<MutablePsychomatrix, List<Operation>>()
 
     init {
         openPsychomatrixChangedSubscription().subscribe {
@@ -33,7 +34,7 @@ class ModifyPsychomatrixPresenterImpl(
         return modifyPsychomatrixUseCase.openPsychomatrixChangedSubscription()
     }
 
-    override suspend fun tryToDoOperation(psychomatrix: Psychomatrix, operation: Operation): Deferred<Boolean> {
+    override suspend fun tryToDoOperation(psychomatrix: MutablePsychomatrix, operation: Operation): Deferred<Boolean> {
         return modifyPsychomatrixUseCase.makeConvert(psychomatrix, operation)
     }
 
@@ -93,7 +94,7 @@ class ModifyPsychomatrixPresenterImpl(
         }
     }
 
-    override suspend fun rollback(psychomatrix: Psychomatrix, operations: Int): Job {
+    override suspend fun rollback(psychomatrix: MutablePsychomatrix, operations: Int): Job {
         return launch {
             history(psychomatrix).await().let {
                 it.subList(it.size - operations, it.size).asReversed()
@@ -103,7 +104,7 @@ class ModifyPsychomatrixPresenterImpl(
         }
     }
 
-    override suspend fun history(psychomatrix: Psychomatrix): Deferred<List<Operation>> {
+    override suspend fun history(psychomatrix: MutablePsychomatrix): Deferred<List<Operation>> {
         return async {
             availableInverts[psychomatrix] ?: updateInvertsOfPsychomatrix(psychomatrix)
         }
@@ -115,7 +116,7 @@ class ModifyPsychomatrixPresenterImpl(
         }
     }
 
-    private suspend fun updateInvertsOfPsychomatrix(psychomatrix: Psychomatrix): List<Operation> {
+    private suspend fun updateInvertsOfPsychomatrix(psychomatrix: MutablePsychomatrix): List<Operation> {
         return modifyPsychomatrixUseCase.getInverts(psychomatrix).await().also {
             availableInverts[psychomatrix] = it
         }
diff --git a/src/main/kotlin/com/github/insanusmokrassar/PsychomatrixBase/presentation/presenters/ModifyPsychomatrixPresenter.kt b/src/main/kotlin/com/github/insanusmokrassar/PsychomatrixBase/presentation/presenters/ModifyPsychomatrixPresenter.kt
index 62e359e..658c4bc 100644
--- a/src/main/kotlin/com/github/insanusmokrassar/PsychomatrixBase/presentation/presenters/ModifyPsychomatrixPresenter.kt
+++ b/src/main/kotlin/com/github/insanusmokrassar/PsychomatrixBase/presentation/presenters/ModifyPsychomatrixPresenter.kt
@@ -1,6 +1,7 @@
 package com.github.insanusmokrassar.PsychomatrixBase.presentation.presenters
 
 import com.github.insanusmokrassar.PsychomatrixBase.domain.UseCases.PsychomatrixOperationIsConvert
+import com.github.insanusmokrassar.PsychomatrixBase.domain.entities.MutablePsychomatrix
 import com.github.insanusmokrassar.PsychomatrixBase.domain.entities.Psychomatrix
 import com.github.insanusmokrassar.PsychomatrixBase.domain.entities.operations.Operation
 import kotlinx.coroutines.experimental.Deferred
@@ -11,7 +12,7 @@ interface ModifyPsychomatrixPresenter {
 
     fun openPsychomatrixChangedSubscription(): ReceiveChannel<PsychomatrixOperationIsConvert>
 
-    suspend fun tryToDoOperation(psychomatrix: Psychomatrix, operation: Operation): Deferred<Boolean>
+    suspend fun tryToDoOperation(psychomatrix: MutablePsychomatrix, operation: Operation): Deferred<Boolean>
 
     suspend fun twoGrowFourAvailable(psychomatrix: Psychomatrix): Deferred<Boolean>
     suspend fun fourGrowTwoAvailable(psychomatrix: Psychomatrix): Deferred<Boolean>
@@ -27,7 +28,7 @@ interface ModifyPsychomatrixPresenter {
 
     suspend fun customGrowAvailable(psychomatrix: Psychomatrix, number: Byte): Deferred<Boolean>
 
-    suspend fun rollback(psychomatrix: Psychomatrix, operations: Int): Job
+    suspend fun rollback(psychomatrix: MutablePsychomatrix, operations: Int): Job
 
-    suspend fun history(psychomatrix: Psychomatrix): Deferred<List<Operation>>
+    suspend fun history(psychomatrix: MutablePsychomatrix): Deferred<List<Operation>>
 }
\ No newline at end of file