diff --git a/repos/inmemory/src/commonTest/kotlin/MapCRUDRepoTest.kt b/repos/inmemory/src/commonTest/kotlin/MapCRUDRepoTest.kt
new file mode 100644
index 00000000000..fc386c3971c
--- /dev/null
+++ b/repos/inmemory/src/commonTest/kotlin/MapCRUDRepoTest.kt
@@ -0,0 +1,100 @@
+import dev.inmo.micro_utils.repos.MapCRUDRepo
+import dev.inmo.micro_utils.repos.create
+import kotlinx.coroutines.Dispatchers
+import kotlinx.coroutines.delay
+import kotlinx.coroutines.launch
+import kotlinx.coroutines.test.runTest
+import kotlin.test.Test
+import kotlin.test.assertEquals
+
+data class TestModel(
+    val testery: String,
+    val isTestery: Boolean,
+    val testeryAmount: Int
+)
+
+class MapCRUDRepoTest {
+    /**
+     * A utility function used for generating non-intersecting ranges in cyclic environment, like [repeat]
+     * or for-loops
+     */
+    private fun getIdRange(start: Int, base: Int) = (start * base)..(start * base + (base - 1))
+
+    @Test
+    fun mapCrudRepoTest() = runTest {
+        val base = 200 // define a bigger number to increase test intensity
+        val targetMap = mutableMapOf<Int, TestModel>()
+
+        // filling the map
+        val jobs = List(base) { id ->
+            launch(Dispatchers.Default) { // to make delays work
+                println("launching job $id")
+                delay((1..5).random().toLong())
+
+                val idsList = getIdRange(id, base).toMutableList()
+                println("created ids list $idsList")
+                val mapCRUDRepo = MapCRUDRepo<TestModel, Int, TestModel>(
+                    targetMap,
+                    createCallback = { new ->
+                        val newObject = idsList.first() to new
+                        idsList.remove(newObject.first)
+                        println("created $newObject in map")
+                        newObject
+                    },
+                    updateCallback = { new, id, old ->
+                        println("updated object at $id from $old to $new")
+                        new
+                    }
+                )
+                for (i in getIdRange(id, base)) {
+                    val newModel = TestModel(
+                        testery = "testery$i",
+                        isTestery = i % 2 == 0,
+                        testeryAmount = i
+                    )
+                    mapCRUDRepo.create(newModel)
+                }
+            }
+        }
+
+        jobs.forEach {
+            println("joining job ${it.hashCode()}")
+            it.join()
+        }
+
+        // validating the map
+        val validationJobs = List(base) { id ->
+            launch {
+                val idsList = getIdRange(id, base).toMutableList()
+                val mapCRUDRepo = MapCRUDRepo<TestModel, Int, TestModel>(
+                    targetMap,
+                    // these will not be used
+                    createCallback = { new ->
+                        val newObject = idsList.first() to new
+                        idsList.remove(newObject.first)
+                        println("created $newObject in map")
+                        newObject
+                    },
+                    updateCallback = { new, id, old ->
+                        println("updated object at $id from $old to $new")
+                        new
+                    }
+                )
+                for (i in getIdRange(id, base)) {
+                    val newModel = TestModel(
+                        testery = "testery$i",
+                        isTestery = i % 2 == 0,
+                        testeryAmount = i
+                    )
+                    val oldModel = mapCRUDRepo.getById(i)
+                    assertEquals(newModel, oldModel)
+                }
+            }
+        }
+
+        validationJobs.forEach {
+            println("joining validation job ${it.hashCode()}")
+            it.join()
+        }
+    }
+}
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