diff --git a/src/main/java/ru/vk/itmo/podobaalexandr/InMemoryDaoImpl.java b/src/main/java/ru/vk/itmo/podobaalexandr/InMemoryDaoImpl.java
new file mode 100644
index 000000000..506096ee1
--- /dev/null
+++ b/src/main/java/ru/vk/itmo/podobaalexandr/InMemoryDaoImpl.java
@@ -0,0 +1,61 @@
+package ru.vk.itmo.podobaalexandr;
+
+import ru.vk.itmo.Dao;
+import ru.vk.itmo.Entry;
+
+import java.lang.foreign.MemorySegment;
+import java.lang.foreign.ValueLayout;
+import java.util.Comparator;
+import java.util.Iterator;
+import java.util.concurrent.ConcurrentNavigableMap;
+import java.util.concurrent.ConcurrentSkipListMap;
+
+public class InMemoryDaoImpl implements Dao<MemorySegment, Entry<MemorySegment>> {
+    ConcurrentNavigableMap<MemorySegment, Entry<MemorySegment>> memorySegmentEntryMap
+            = new ConcurrentSkipListMap<>(new MyComparator());
+
+    @Override
+    public Iterator<Entry<MemorySegment>> get(MemorySegment from, MemorySegment to) {
+        ConcurrentNavigableMap<MemorySegment, Entry<MemorySegment>> innerMap = memorySegmentEntryMap;
+
+        if (from != null && to == null) {
+            innerMap = innerMap.tailMap(from);
+        } else if (from == null && to != null) {
+            innerMap = innerMap.headMap(to);
+        } else if (from != null) {
+            innerMap = innerMap.subMap(from, to);
+        }
+
+        return innerMap.values().iterator();
+    }
+
+    @Override
+    public void upsert(Entry<MemorySegment> entry) {
+        memorySegmentEntryMap.put(entry.key(), entry);
+    }
+
+    @Override
+    public Entry<MemorySegment> get(MemorySegment key) {
+        return memorySegmentEntryMap.get(key);
+    }
+
+    private static class MyComparator implements Comparator<MemorySegment> {
+
+        @Override
+        public int compare(MemorySegment o1, MemorySegment o2) {
+
+            int sizeDiff = Long.compare(o1.byteSize(), o2.byteSize());
+            long mismatch = o1.mismatch(o2);
+
+            if (o1.byteSize() != 0 && o2.byteSize() != 0) {
+                int diff = mismatch == -1
+                        ? 0
+                        : o1.get(ValueLayout.JAVA_BYTE, mismatch) - o2.get(ValueLayout.JAVA_BYTE, mismatch);
+                return diff == 0 ? sizeDiff : diff;
+            }
+
+            return sizeDiff;
+        }
+    }
+
+}
diff --git a/src/main/java/ru/vk/itmo/test/podobaalexandr/FactoryImpl.java b/src/main/java/ru/vk/itmo/test/podobaalexandr/FactoryImpl.java
new file mode 100644
index 000000000..3228df850
--- /dev/null
+++ b/src/main/java/ru/vk/itmo/test/podobaalexandr/FactoryImpl.java
@@ -0,0 +1,35 @@
+package ru.vk.itmo.test.podobaalexandr;
+
+import ru.vk.itmo.Dao;
+import ru.vk.itmo.Entry;
+import ru.vk.itmo.podobaalexandr.InMemoryDaoImpl;
+import ru.vk.itmo.test.DaoFactory;
+
+import java.lang.foreign.MemorySegment;
+import java.lang.foreign.ValueLayout;
+import java.nio.charset.StandardCharsets;
+
+@SuppressWarnings("unused")
+@DaoFactory
+public class FactoryImpl implements DaoFactory.Factory<MemorySegment, Entry<MemorySegment>> {
+    @Override
+    public Dao<MemorySegment, Entry<MemorySegment>> createDao() {
+        return new InMemoryDaoImpl();
+    }
+
+    @Override
+    public String toString(MemorySegment memorySegment) {
+        return new String((byte[]) memorySegment.heapBase()
+                .orElse(memorySegment.toArray(ValueLayout.JAVA_BYTE)), StandardCharsets.UTF_8);
+    }
+
+    @Override
+    public MemorySegment fromString(String data) {
+        return data == null ? null : MemorySegment.ofArray(data.getBytes(StandardCharsets.UTF_8));
+    }
+
+    @Override
+    public Entry<MemorySegment> fromBaseEntry(Entry<MemorySegment> baseEntry) {
+        return baseEntry;
+    }
+}