diff --git a/src/main/java/net/openhft/chronicle/map/ChronicleMapBuilder.java b/src/main/java/net/openhft/chronicle/map/ChronicleMapBuilder.java
index 954da6445..70f78cfea 100755
--- a/src/main/java/net/openhft/chronicle/map/ChronicleMapBuilder.java
+++ b/src/main/java/net/openhft/chronicle/map/ChronicleMapBuilder.java
@@ -98,7 +98,6 @@ public final class ChronicleMapBuilder<K, V> implements
         ChronicleHashBuilder<K, ChronicleMap<K, V>, ChronicleMapBuilder<K, V>> {
 
     static final byte UDP_REPLICATION_MODIFICATION_ITERATOR_ID = (byte) 127;
-    private static final long DEFAULT_ENTRIES = 1 << 20;
 
     private static final int UNDEFINED_ALIGNMENT_CONFIG = -1;
     private static final int NO_ALIGNMENT = 1;
@@ -731,8 +730,12 @@ public final class ChronicleMapBuilder<K, V> implements
     }
 
     long entries() {
-        if (entries < 0)
-            return DEFAULT_ENTRIES;
+        if (entries < 0) {
+            throw new IllegalStateException("If in-memory Chronicle Map is created or persisted\n" +
+                    "to a file for the first time (i. e. not accessing existing file),\n" +
+                    "ChronicleMapBuilder.entries() must be configured.\n" +
+                    "See Chronicle Map 3 tutorial and javadocs for more information");
+        }
         return entries;
     }
 
diff --git a/src/main/java/net/openhft/chronicle/set/ChronicleSet.java b/src/main/java/net/openhft/chronicle/set/ChronicleSet.java
index 3fe1290e0..974afe6cf 100644
--- a/src/main/java/net/openhft/chronicle/set/ChronicleSet.java
+++ b/src/main/java/net/openhft/chronicle/set/ChronicleSet.java
@@ -23,4 +23,8 @@ import java.util.Set;
 public interface ChronicleSet<K>
         extends Set<K>, ChronicleHash<K, SetEntry<K>, SetSegmentContext<K, ?>,
         ExternalSetQueryContext<K, ?>> {
+
+    static <K> ChronicleSetBuilder<K> of(Class<K> keyClass) {
+        return ChronicleSetBuilder.of(keyClass);
+    }
 }
diff --git a/src/test/java/net/openhft/chronicle/TestReplication.java b/src/test/java/net/openhft/chronicle/TestReplication.java
index 6d8fe24e0..d7d1b00f4 100755
--- a/src/test/java/net/openhft/chronicle/TestReplication.java
+++ b/src/test/java/net/openhft/chronicle/TestReplication.java
@@ -47,12 +47,14 @@ public class TestReplication {
         final ChronicleMap<Integer, Integer> map2 = ChronicleMapBuilder.of(Integer.class,
                 Integer.class)
                 .replication((byte) 2, tcpConfigServer2)
+                .entries(70000)
                 .create();
 
 
         final ChronicleMap<Integer, Integer> map1 = ChronicleMapBuilder.of(Integer.class,
                 Integer.class)
                 .replication((byte) 3, tcpConfigServer1)
+                .entries(70000)
                 .create();
 
 
diff --git a/src/test/java/net/openhft/chronicle/map/BooleanValuesTest.java b/src/test/java/net/openhft/chronicle/map/BooleanValuesTest.java
index 7807ec881..ff8b5292f 100644
--- a/src/test/java/net/openhft/chronicle/map/BooleanValuesTest.java
+++ b/src/test/java/net/openhft/chronicle/map/BooleanValuesTest.java
@@ -31,8 +31,8 @@ public class BooleanValuesTest {
      */
     @Test
     public void testTestBooleanValues() throws IOException, InterruptedException {
-        try (ChronicleMap<Integer, Boolean> map =
-                     ChronicleMapBuilder.of(Integer.class, Boolean.class).create()) {
+        try (ChronicleMap<Integer, Boolean> map = ChronicleMap.of(Integer.class, Boolean.class)
+                .entries(1).create()) {
             map.put(7, true);
             Assert.assertEquals(true, map.get(7));
         }
diff --git a/src/test/java/net/openhft/chronicle/map/BuildVersionTest.java b/src/test/java/net/openhft/chronicle/map/BuildVersionTest.java
index 5147a50db..acf7dfadc 100644
--- a/src/test/java/net/openhft/chronicle/map/BuildVersionTest.java
+++ b/src/test/java/net/openhft/chronicle/map/BuildVersionTest.java
@@ -44,9 +44,8 @@ public class BuildVersionTest {
     @Test
     public void testVersion() throws IOException, InterruptedException {
 
-        try (ChronicleMap<Integer, Double> expected = ChronicleMapBuilder.of(Integer.class, Double
-                .class)
-                .create()) {
+        try (ChronicleMap<Integer, Double> expected = ChronicleMap.of(Integer.class, Double.class)
+                .entries(1).create()) {
             expected.put(1, 1.0);
 
             String version = ((VanillaChronicleMap) expected).persistedDataVersion();
diff --git a/src/test/java/net/openhft/chronicle/map/CHMUseCasesTest.java b/src/test/java/net/openhft/chronicle/map/CHMUseCasesTest.java
index 5f61dce89..c85ecd259 100644
--- a/src/test/java/net/openhft/chronicle/map/CHMUseCasesTest.java
+++ b/src/test/java/net/openhft/chronicle/map/CHMUseCasesTest.java
@@ -407,7 +407,8 @@ public class CHMUseCasesTest {
         Arrays.fill(expected, 'X');
 
         ChronicleMapBuilder<CharSequence, char[]> builder = ChronicleMapBuilder
-                .of(CharSequence.class, char[].class);
+                .of(CharSequence.class, char[].class)
+                .entries(1);
 
         try (ChronicleMap<CharSequence, char[]> map = newInstance(builder)) {
             map.put("Key", expected);
@@ -423,6 +424,7 @@ public class CHMUseCasesTest {
 
         ChronicleMapBuilder<byte[], byte[][]> builder = ChronicleMapBuilder
                 .of(byte[].class, byte[][].class)
+                .entries(1)
                 .averageKey("Key".getBytes())
                 .averageValue(new byte[][]{"value1".getBytes(), "value2".getBytes()});
 
@@ -441,6 +443,7 @@ public class CHMUseCasesTest {
     public void bondExample() throws IOException, InterruptedException {
 
         ChronicleMapBuilder builder = ChronicleMapBuilder.of(String.class, BondVOInterface.class)
+                .entries(1)
                 .averageKeySize(10);
 
         try (ChronicleMap<String, BondVOInterface> chm = newInstance(builder)) {
@@ -495,6 +498,7 @@ public class CHMUseCasesTest {
 
         ChronicleMapBuilder<CharSequence, char[]> builder = ChronicleMapBuilder
                 .of(CharSequence.class, char[].class)
+                .entries(100)
                 .averageKeySize(10)
                 .averageValueSize(10);
 
@@ -550,7 +554,8 @@ public class CHMUseCasesTest {
 
 
         ChronicleMapBuilder<String, String> builder = ChronicleMapBuilder
-                .of(String.class, String.class);
+                .of(String.class, String.class)
+                .entries(1);
 
         try (ChronicleMap<String, String> map = newInstance(builder)) {
             map.put("Hello", "World");
@@ -583,7 +588,8 @@ public class CHMUseCasesTest {
     public void testStringStringMapMutableValue() throws ExecutionException, InterruptedException, IOException {
 
         ChronicleMapBuilder<String, String> builder = ChronicleMapBuilder
-                .of(String.class, String.class);
+                .of(String.class, String.class)
+                .entries(1);
 
         try (ChronicleMap<String, String> map = newInstance(builder)) {
             map.put("Hello", "World");
@@ -596,7 +602,8 @@ public class CHMUseCasesTest {
     public void testCharSequenceMixingKeyTypes() throws ExecutionException, InterruptedException, IOException {
 
         ChronicleMapBuilder<CharSequence, CharSequence> builder = ChronicleMapBuilder
-                .of(CharSequence.class, CharSequence.class);
+                .of(CharSequence.class, CharSequence.class)
+                .entries(1);
 
         try (ChronicleMap<CharSequence, CharSequence> map = newInstance(builder)) {
 
@@ -612,7 +619,8 @@ public class CHMUseCasesTest {
     public void testCharSequenceMixingValueTypes() throws ExecutionException, InterruptedException, IOException {
 
         ChronicleMapBuilder<CharSequence, CharSequence> builder = ChronicleMapBuilder
-                .of(CharSequence.class, CharSequence.class);
+                .of(CharSequence.class, CharSequence.class)
+                .entries(2);
 
         try (ChronicleMap<CharSequence, CharSequence> map = newInstance(builder)) {
             map.put("Hello", "World");
@@ -635,7 +643,8 @@ public class CHMUseCasesTest {
 
 
         ChronicleMapBuilder<CharSequence, CharSequence> builder = ChronicleMapBuilder
-                .of(CharSequence.class, CharSequence.class);
+                .of(CharSequence.class, CharSequence.class)
+                .entries(10);
 
         try (ChronicleMap<CharSequence, CharSequence> map = newInstance(builder)) {
             map.put("Hello", "World");
@@ -679,7 +688,8 @@ public class CHMUseCasesTest {
 
 
         ChronicleMapBuilder<CharSequence, CharSequence> builder = ChronicleMapBuilder
-                .of(CharSequence.class, CharSequence.class);
+                .of(CharSequence.class, CharSequence.class)
+                .entries(1);
 
         try (ChronicleMap<CharSequence, CharSequence> map = newInstance(builder)) {
 
@@ -699,7 +709,8 @@ public class CHMUseCasesTest {
     public void testGetUsingWithIntValueNoValue() throws IOException {
 
         ChronicleMapBuilder<CharSequence, IntValue> builder = ChronicleMapBuilder
-                .of(CharSequence.class, IntValue.class);
+                .of(CharSequence.class, IntValue.class)
+                .entries(1);
 
         try (ChronicleMap<CharSequence, IntValue> map = newInstance(builder)) {
 
@@ -716,7 +727,8 @@ public class CHMUseCasesTest {
     public void testAcquireUsingImmutableUsing() throws IOException {
 
         ChronicleMapBuilder<IntValue, CharSequence> builder = ChronicleMapBuilder
-                .of(IntValue.class, CharSequence.class);
+                .of(IntValue.class, CharSequence.class)
+                .entries(1);
 
         try (ChronicleMap<IntValue, CharSequence> map = newInstance(builder)) {
 
@@ -738,7 +750,8 @@ public class CHMUseCasesTest {
     public void testAcquireUsingWithIntValueKeyStringBuilderValue() throws IOException {
 
         ChronicleMapBuilder<IntValue, StringBuilder> builder = ChronicleMapBuilder
-                .of(IntValue.class, StringBuilder.class);
+                .of(IntValue.class, StringBuilder.class)
+                .entries(1);
 
         try (ChronicleMap<IntValue, StringBuilder> map = newInstance(builder)) {
 
@@ -761,7 +774,8 @@ public class CHMUseCasesTest {
     public void testAcquireUsingWithIntValueKey() throws IOException {
 
         ChronicleMapBuilder<IntValue, CharSequence> builder = ChronicleMapBuilder
-                .of(IntValue.class, CharSequence.class);
+                .of(IntValue.class, CharSequence.class)
+                .entries(3);
 
         try (ChronicleMap<IntValue, CharSequence> map = newInstance(builder)) {
 
@@ -799,7 +813,8 @@ public class CHMUseCasesTest {
     public void testStringValueStringValueMap() throws IOException {
 
         ChronicleMapBuilder<StringValue, StringValue> builder = ChronicleMapBuilder
-                .of(StringValue.class, StringValue.class);
+                .of(StringValue.class, StringValue.class)
+                .entries(10);
 
         try (ChronicleMap<StringValue, StringValue> map = newInstance(builder)) {
             StringValue key1 = map.newKeyInstance();
@@ -935,7 +950,8 @@ public class CHMUseCasesTest {
             throws ExecutionException, InterruptedException, IOException {
 
         ChronicleMapBuilder<Integer, Integer> builder = ChronicleMapBuilder
-                .of(Integer.class, Integer.class);
+                .of(Integer.class, Integer.class)
+                .entries(10);
 
         try (ChronicleMap<Integer, Integer> map = newInstance(builder)) {
 
@@ -995,7 +1011,8 @@ public class CHMUseCasesTest {
 
 
         ChronicleMapBuilder<Long, Long> builder = ChronicleMapBuilder
-                .of(Long.class, Long.class);
+                .of(Long.class, Long.class)
+                .entries(10);
 
         try (ChronicleMap<Long, Long> map = newInstance(builder)) {
 //            assertEquals(16, entrySize(map));
@@ -1035,7 +1052,8 @@ public class CHMUseCasesTest {
 
 
         ChronicleMapBuilder<Double, Double> builder = ChronicleMapBuilder
-                .of(Double.class, Double.class);
+                .of(Double.class, Double.class)
+                .entries(10);
 
         try (ChronicleMap<Double, Double> map = newInstance(builder)) {
 
@@ -1321,7 +1339,8 @@ public class CHMUseCasesTest {
     public void testIntValueIntValueMap() throws IOException {
 
         ChronicleMapBuilder<IntValue, IntValue> builder = ChronicleMapBuilder
-                .of(IntValue.class, IntValue.class);
+                .of(IntValue.class, IntValue.class)
+                .entries(10);
 
         try (ChronicleMap<IntValue, IntValue> map = newInstance(builder)) {
             // this may change due to alignment
@@ -1431,7 +1450,8 @@ public class CHMUseCasesTest {
     public void testUnsignedIntValueUnsignedIntValueMap() throws IOException {
 
         ChronicleMapBuilder<UnsignedIntValue, UnsignedIntValue> builder = ChronicleMapBuilder
-                .of(UnsignedIntValue.class, UnsignedIntValue.class);
+                .of(UnsignedIntValue.class, UnsignedIntValue.class)
+                .entries(10);
 
         try (ChronicleMap<UnsignedIntValue, UnsignedIntValue> map = newInstance(builder)) {
 
@@ -1547,7 +1567,8 @@ public class CHMUseCasesTest {
     public void testIntValueShortValueMap() throws IOException {
 
         ChronicleMapBuilder<IntValue, ShortValue> builder = ChronicleMapBuilder
-                .of(IntValue.class, ShortValue.class);
+                .of(IntValue.class, ShortValue.class)
+                .entries(10);
 
         try (ChronicleMap<IntValue, ShortValue> map = newInstance(builder)) {
 
@@ -1659,7 +1680,8 @@ public class CHMUseCasesTest {
     public void testIntValueUnsignedShortValueMap() throws IOException {
 
         ChronicleMapBuilder<IntValue, UnsignedShortValue> builder = ChronicleMapBuilder
-                .of(IntValue.class, UnsignedShortValue.class);
+                .of(IntValue.class, UnsignedShortValue.class)
+                .entries(10);
 
         try (ChronicleMap<IntValue, UnsignedShortValue> map = newInstance(builder)) {
 
@@ -1763,7 +1785,8 @@ public class CHMUseCasesTest {
     public void testIntValueCharValueMap() throws IOException {
 
         ChronicleMapBuilder<IntValue, CharValue> builder = ChronicleMapBuilder
-                .of(IntValue.class, CharValue.class);
+                .of(IntValue.class, CharValue.class)
+                .entries(10);
 
         try (ChronicleMap<IntValue, CharValue> map = newInstance(builder)) {
 
@@ -1868,7 +1891,8 @@ public class CHMUseCasesTest {
     public void testIntValueUnsignedByteMap() throws IOException {
 
         ChronicleMapBuilder<IntValue, UnsignedByteValue> builder = ChronicleMapBuilder
-                .of(IntValue.class, UnsignedByteValue.class);
+                .of(IntValue.class, UnsignedByteValue.class)
+                .entries(10);
 
         try (ChronicleMap<IntValue, UnsignedByteValue> map = newInstance(builder)) {
 
@@ -1974,7 +1998,8 @@ public class CHMUseCasesTest {
     public void testIntValueBooleanValueMap() throws IOException {
 
         ChronicleMapBuilder<IntValue, BooleanValue> builder = ChronicleMapBuilder
-                .of(IntValue.class, BooleanValue.class);
+                .of(IntValue.class, BooleanValue.class)
+                .entries(10);
 
         try (ChronicleMap<IntValue, BooleanValue> map = newInstance(builder)) {
 
@@ -2077,7 +2102,8 @@ public class CHMUseCasesTest {
     public void testFloatValueFloatValueMap() throws IOException {
 
         ChronicleMapBuilder<FloatValue, FloatValue> builder = ChronicleMapBuilder
-                .of(FloatValue.class, FloatValue.class);
+                .of(FloatValue.class, FloatValue.class)
+                .entries(10);
 
         try (ChronicleMap<FloatValue, FloatValue> map = newInstance(builder)) {
 
@@ -2180,7 +2206,8 @@ public class CHMUseCasesTest {
     public void testDoubleValueDoubleValueMap() throws IOException {
 
         ChronicleMapBuilder<DoubleValue, DoubleValue> builder = ChronicleMapBuilder
-                .of(DoubleValue.class, DoubleValue.class);
+                .of(DoubleValue.class, DoubleValue.class)
+                .entries(10);
 
         try (ChronicleMap<DoubleValue, DoubleValue> map = newInstance(builder)) {
 
@@ -2287,7 +2314,8 @@ public class CHMUseCasesTest {
     public void testLongValueLongValueMap() throws IOException {
 
         ChronicleMapBuilder<LongValue, LongValue> builder = ChronicleMapBuilder
-                .of(LongValue.class, LongValue.class);
+                .of(LongValue.class, LongValue.class)
+                .entries(10);
 
         try (ChronicleMap<LongValue, LongValue> map = newInstance(builder)) {
 
@@ -2384,13 +2412,6 @@ public class CHMUseCasesTest {
         }
     }
 
-    /**
-     * For beans, the key can be on heap or off heap as long as the bean is not variable length.
-     */
-    @Test
-    public void testBeanBeanMap() {
-    }
-
     @Test
     public void testListValue() throws IOException {
 
@@ -2398,6 +2419,7 @@ public class CHMUseCasesTest {
                 new StringBytesReader(), CharSequenceBytesWriter.INSTANCE);
         ChronicleMapBuilder<String, List<String>> builder = ChronicleMapBuilder
                 .of(String.class, (Class<List<String>>) (Class) List.class)
+                .entries(2)
                 .valueMarshaller(valueMarshaller);
 
 
@@ -2445,6 +2467,7 @@ public class CHMUseCasesTest {
                 new StringBytesReader(), CharSequenceBytesWriter.INSTANCE);
         ChronicleMapBuilder<String, Set<String>> builder = ChronicleMapBuilder
                 .of(String.class, (Class<Set<String>>) (Class) Set.class)
+                .entries(10)
                 .valueMarshaller(valueMarshaller);
 
 
@@ -2493,6 +2516,7 @@ public class CHMUseCasesTest {
                 new StringBytesReader(), CharSequenceBytesWriter.INSTANCE);
         ChronicleMapBuilder<String, Map<String, String>> builder = ChronicleMapBuilder
                 .of(String.class, (Class<Map<String, String>>) (Class) Map.class)
+                .entries(2)
                 .valueMarshaller(valueMarshaller);
 
 
@@ -2535,6 +2559,7 @@ public class CHMUseCasesTest {
                 IntegerMarshaller.INSTANCE, IntegerMarshaller.INSTANCE);
         ChronicleMapBuilder<String, Map<String, Integer>> builder = ChronicleMapBuilder
                 .of(String.class, (Class<Map<String, Integer>>) (Class) Map.class)
+                .entries(10)
                 .valueMarshaller(valueMarshaller);
 
         try (ChronicleMap<String, Map<String, Integer>> map = newInstance(builder)) {
@@ -2571,7 +2596,8 @@ public class CHMUseCasesTest {
     @Test
     public void testMapStringIntegerValueWithoutListMarshallers() throws IOException {
         ChronicleMapBuilder<String, Map<String, Integer>> builder = ChronicleMapBuilder
-                .of(String.class, (Class<Map<String, Integer>>) (Class) Map.class);
+                .of(String.class, (Class<Map<String, Integer>>) (Class) Map.class)
+                .entries(2);
         try (ChronicleMap<String, Map<String, Integer>> map = newInstance(builder)) {
             map.put("1", Collections.<String, Integer>emptyMap());
             map.put("2", mapOf("two", 2));
diff --git a/src/test/java/net/openhft/chronicle/map/ChronicleMapImportExportTest.java b/src/test/java/net/openhft/chronicle/map/ChronicleMapImportExportTest.java
index 301300245..8e8e41fa9 100644
--- a/src/test/java/net/openhft/chronicle/map/ChronicleMapImportExportTest.java
+++ b/src/test/java/net/openhft/chronicle/map/ChronicleMapImportExportTest.java
@@ -129,16 +129,14 @@ public class ChronicleMapImportExportTest {
         File file = new File(TMP + "/chronicle-map-" + System.nanoTime() + ".json");
         file.deleteOnExit();
 
-        try (ChronicleMap<Integer, Double> expected = ChronicleMapBuilder.of(Integer.class, Double
-                .class)
-                .create()) {
+        try (ChronicleMap<Integer, Double> expected = ChronicleMap.of(Integer.class, Double.class)
+                .entries(1).create()) {
             expected.put(1, 1.0);
 
             expected.getAll(file);
 
-            try (ChronicleMap<Integer, Double> actual = ChronicleMapBuilder.of(Integer.class, Double
-                    .class)
-                    .create()) {
+            try (ChronicleMap<Integer, Double> actual = ChronicleMap.of(Integer.class, Double.class)
+                    .entries(1).create()) {
                 actual.putAll(file);
 
                 Assert.assertEquals(expected, actual);
diff --git a/src/test/java/net/openhft/chronicle/map/ChronicleMapTest.java b/src/test/java/net/openhft/chronicle/map/ChronicleMapTest.java
index 5e000a220..f64c7b36e 100755
--- a/src/test/java/net/openhft/chronicle/map/ChronicleMapTest.java
+++ b/src/test/java/net/openhft/chronicle/map/ChronicleMapTest.java
@@ -139,6 +139,7 @@ public class ChronicleMapTest {
         try (final ChronicleMap<CharSequence, CharSequence> map =
                      ChronicleMapBuilder
                              .of(CharSequence.class, CharSequence.class)
+                             .entries(10)
                              .averageKey("key1").averageValue("one")
                              .minSegments(2).create()) {
 
@@ -186,8 +187,8 @@ public class ChronicleMapTest {
         final File persistenceFile = Builder.getPersistenceFile();
 
         for (int i = 0; i < 3; i++) {
-            try (ChronicleMap<byte[], byte[]> map = ChronicleMapBuilder
-                    .of(byte[].class, byte[].class)
+            try (ChronicleMap<byte[], byte[]> map = ChronicleMap.of(byte[].class, byte[].class)
+                    .entries(1)
                     .averageKey("hello".getBytes()).averageValue("world".getBytes())
                     .createPersistedTo(persistenceFile)) {
 
@@ -205,6 +206,7 @@ public class ChronicleMapTest {
 
         ChronicleMapBuilder<CharSequence, CharSequence> builder = ChronicleMapBuilder
                 .of(CharSequence.class, CharSequence.class)
+                .entries(1)
                 .averageKey("hello").averageValue("world");
 
         try (final ChronicleMap<CharSequence, CharSequence> map1 = builder.create()) {
@@ -228,6 +230,7 @@ public class ChronicleMapTest {
 
         ChronicleMapBuilder<CharSequence, char[]> builder = ChronicleMapBuilder
                 .of(CharSequence.class, char[].class)
+                .entries(1)
                 .averageKey("hello").averageValue(value);
 
         try (final ChronicleMap<CharSequence, char[]> map1 = builder.create()) {
@@ -252,6 +255,7 @@ public class ChronicleMapTest {
 
         ChronicleMapBuilder<CharSequence, byte[]> builder = ChronicleMapBuilder
                 .of(CharSequence.class, byte[].class)
+                .entries(1)
                 .averageKey("hello").averageValue(value);
 
         try (final ChronicleMap<CharSequence, byte[]> map1 = builder.create()) {
@@ -272,9 +276,10 @@ public class ChronicleMapTest {
     public void testSize() {
 
         try (final ChronicleMap<CharSequence, CharSequence> map =
-                     ChronicleMapBuilder.of(CharSequence.class, CharSequence.class)
+                     ChronicleMap.of(CharSequence.class, CharSequence.class)
                              .averageKey("key-1024").averageValue("value")
                              .minSegments(1024)
+                             .entries(1024)
                              .removeReturnsNull(true).create()) {
 
             for (int i = 1; i < 1024; i++) {
@@ -321,6 +326,7 @@ public class ChronicleMapTest {
 
         try (final ChronicleMap<CharSequence, CharSequence> map =
                      ChronicleMapBuilder.of(CharSequence.class, CharSequence.class)
+                             .entries(10)
                              .averageKey("key1").averageValue("one")
                              .minSegments(2)
                              .removeReturnsNull(true).create()) {
@@ -368,6 +374,7 @@ public class ChronicleMapTest {
 
         try (final ChronicleMap<CharSequence, CharSequence> map =
                      ChronicleMapBuilder.of(CharSequence.class, CharSequence.class)
+                             .entries(10)
                              .averageKey("key1").averageValue("one")
                              .minSegments(2).create()) {
 
@@ -433,6 +440,7 @@ public class ChronicleMapTest {
 
         try (final ChronicleMap<CharSequence, CharSequence> map =
                      ChronicleMapBuilder.of(CharSequence.class, CharSequence.class)
+                             .entries(10)
                              .averageKey("key1").averageValue("one")
                              .minSegments(2).create()) {
 
@@ -476,6 +484,7 @@ public class ChronicleMapTest {
 
         try (final ChronicleMap<CharSequence, CharSequence> map =
                      ChronicleMapBuilder.of(CharSequence.class, CharSequence.class)
+                             .entries(10)
                              .averageKey("key1").averageValue("one")
                              .minSegments(2).create()) {
 
@@ -1682,14 +1691,13 @@ public class ChronicleMapTest {
     @Test
     public void equalsTest() throws IOException {
         try (final ChronicleMap<Integer, String> map1 = ChronicleMap.of(Integer.class, String.class)
-                .averageValue("one").create()) {
+                .averageValue("one").entries(2).create()) {
 
             map1.put(1, "one");
             map1.put(2, "two");
 
-            try (final ChronicleMap<Integer, String> map2 = ChronicleMapBuilder
-                    .of(Integer.class, String.class)
-                    .averageValue("one").create()) {
+            try (ChronicleMap<Integer, String> map2 = ChronicleMap.of(Integer.class, String.class)
+                    .averageValue("one").entries(2).create()) {
 
                 map2.put(1, "one");
                 map2.put(2, "two");
diff --git a/src/test/java/net/openhft/chronicle/map/DefaultValueTest.java b/src/test/java/net/openhft/chronicle/map/DefaultValueTest.java
index 74ce6db6f..5d5ccc781 100644
--- a/src/test/java/net/openhft/chronicle/map/DefaultValueTest.java
+++ b/src/test/java/net/openhft/chronicle/map/DefaultValueTest.java
@@ -40,8 +40,9 @@ public class DefaultValueTest {
             defaultValue.add(42);
             ListMarshaller<Integer> valueMarshaller =
                     new ListMarshaller<>(IntegerMarshaller.INSTANCE, IntegerMarshaller.INSTANCE);
-            try (ChronicleMap<String, List<Integer>> map = ChronicleMapBuilder
+            try (ChronicleMap<String, List<Integer>> map = ChronicleMap
                     .of(String.class, (Class<List<Integer>>) ((Class) List.class))
+                    .entries(1)
                     .valueMarshaller(valueMarshaller)
                     .averageKey("a").averageValue(Arrays.asList(1, 2))
                     .defaultValueProvider(absentEntry ->
@@ -56,9 +57,8 @@ public class DefaultValueTest {
             }
 
             ArrayList<Integer> using = new ArrayList<Integer>();
-            try (ChronicleMap<String, List<Integer>> map = ChronicleMapBuilder
+            try (ChronicleMap<String, List<Integer>> map = ChronicleMap
                     .of(String.class, (Class<List<Integer>>) ((Class) List.class))
-                    .averageKey("a").averageValue(Arrays.asList(1, 2))
                     .defaultValueProvider(absentEntry ->
                             absentEntry.context().wrapValueAsData(defaultValue))
                     .createPersistedTo(file)) {
diff --git a/src/test/java/net/openhft/chronicle/map/Issue37Test.java b/src/test/java/net/openhft/chronicle/map/Issue37Test.java
index bc720cc36..23b0611cc 100644
--- a/src/test/java/net/openhft/chronicle/map/Issue37Test.java
+++ b/src/test/java/net/openhft/chronicle/map/Issue37Test.java
@@ -46,6 +46,7 @@ public class Issue37Test {
 
         File file1 = Builder.getPersistenceFile();
         ChronicleMap<String, String> map1 = ChronicleMapBuilder.of(String.class, String.class)
+                .entries(1)
                 .averageKeySize(10).averageValueSize(10)
                 .instance()
                 .replicatedViaChannel(replicationHub.createChannel(2))
@@ -54,6 +55,7 @@ public class Issue37Test {
 
         File file2 = Builder.getPersistenceFile();
         ChronicleMap<String, String> map2 = ChronicleMapBuilder.of(String.class, String.class)
+                .entries(1)
                 .averageKeySize(10).averageValueSize(10)
                 .instance()
                 .replicatedViaChannel(replicationHub.createChannel(3))
diff --git a/src/test/java/net/openhft/chronicle/map/KeySizesTest.java b/src/test/java/net/openhft/chronicle/map/KeySizesTest.java
index 07a341652..d7d26b3a1 100755
--- a/src/test/java/net/openhft/chronicle/map/KeySizesTest.java
+++ b/src/test/java/net/openhft/chronicle/map/KeySizesTest.java
@@ -32,7 +32,7 @@ public class KeySizesTest {
     public void testDifferentKeySizes() throws IOException {
 
         Map<String, String> map = ChronicleMap.of(String.class, String.class)
-                .averageKeySize(100).averageValueSize(100).create();
+                .entries(100).averageKeySize(100).averageValueSize(100).create();
 
         String k = "";
         for (int i = 0; i < 100; i++) {
diff --git a/src/test/java/net/openhft/chronicle/map/KeyValueInstanceTest.java b/src/test/java/net/openhft/chronicle/map/KeyValueInstanceTest.java
index 8851fdff0..c73ceefdc 100644
--- a/src/test/java/net/openhft/chronicle/map/KeyValueInstanceTest.java
+++ b/src/test/java/net/openhft/chronicle/map/KeyValueInstanceTest.java
@@ -54,8 +54,8 @@ public class KeyValueInstanceTest {
 
     @Test
     public void testNewKeyValueInstanceWithHahMapType() {
-        try (ChronicleMap map = ChronicleMapBuilder
-                .of(HashMap.class, HashMap.class)
+        try (ChronicleMap map = ChronicleMap.of(HashMap.class, HashMap.class)
+                .entries(1)
                 .averageKey(new HashMap()).averageValue(new HashMap())
                 .create()) {
 
@@ -82,8 +82,8 @@ public class KeyValueInstanceTest {
 
     @Test
     public void testNewKeyValueInstanceWithListType() {
-        try (ChronicleMap map = ChronicleMapBuilder
-                .of(HashMap.class, IBean.class)
+        try (ChronicleMap map = ChronicleMap.of(HashMap.class, IBean.class)
+                .entries(1)
                 .averageKey(new HashMap())
                 .create()) {
 
diff --git a/src/test/java/net/openhft/chronicle/map/NestedContextsTest.java b/src/test/java/net/openhft/chronicle/map/NestedContextsTest.java
index 71933934d..7bf72b2a9 100644
--- a/src/test/java/net/openhft/chronicle/map/NestedContextsTest.java
+++ b/src/test/java/net/openhft/chronicle/map/NestedContextsTest.java
@@ -37,8 +37,9 @@ public class NestedContextsTest {
         for (int i = 0; i < 5; i++) {
             averageValue.add(i);
         }
-        ChronicleMap<Integer, Set<Integer>> graph = ChronicleMapBuilder
+        ChronicleMap<Integer, Set<Integer>> graph = ChronicleMap
                 .of(Integer.class, (Class<Set<Integer>>) (Class) Set.class)
+                .entries(10)
                 .averageValue(averageValue)
                 .actualSegments(2)
                 .create();
diff --git a/src/test/java/net/openhft/chronicle/map/TCPSocketReplication3wayPutReturnsNullTest.java b/src/test/java/net/openhft/chronicle/map/TCPSocketReplication3wayPutReturnsNullTest.java
index 474e1f924..4d0534a40 100755
--- a/src/test/java/net/openhft/chronicle/map/TCPSocketReplication3wayPutReturnsNullTest.java
+++ b/src/test/java/net/openhft/chronicle/map/TCPSocketReplication3wayPutReturnsNullTest.java
@@ -49,6 +49,7 @@ public class TCPSocketReplication3wayPutReturnsNullTest {
                 .autoReconnectedUponDroppedConnection(true);
 
         return (T) ChronicleMapBuilder.of(Integer.class, CharSequence.class)
+                .entries(10)
                 .averageValue("EXAMPLE-1")
                 .putReturnsNull(true)
                 .replication(identifier, tcpConfig).create();
diff --git a/src/test/java/net/openhft/chronicle/map/TCPSocketReplicationBootStrapTest.java b/src/test/java/net/openhft/chronicle/map/TCPSocketReplicationBootStrapTest.java
index bf9b473a7..6acad31b5 100644
--- a/src/test/java/net/openhft/chronicle/map/TCPSocketReplicationBootStrapTest.java
+++ b/src/test/java/net/openhft/chronicle/map/TCPSocketReplicationBootStrapTest.java
@@ -98,9 +98,10 @@ public class TCPSocketReplicationBootStrapTest {
                 .heartBeatInterval(1L, TimeUnit.SECONDS)
                 .autoReconnectedUponDroppedConnection(true);
 
-        map1 = (ReplicatedChronicleMap<Integer, CharSequence, ?>)
-                ChronicleMapBuilder.of(Integer.class, CharSequence.class)
-                        .averageValueSize(100)
+        map1 = (ReplicatedChronicleMap<Integer, CharSequence, ?>) ChronicleMap
+                .of(Integer.class, CharSequence.class)
+                .entries(10)
+                .averageValueSize(100)
                 .replication(SingleChronicleHashReplication.builder()
                         .tcpTransportAndNetwork(map1Config)
                         .name("map1")
@@ -115,6 +116,7 @@ public class TCPSocketReplicationBootStrapTest {
         final ReplicatedChronicleMap<Integer, CharSequence, ?> map2a =
                 (ReplicatedChronicleMap<Integer, CharSequence, ?>)
                         ChronicleMapBuilder.of(Integer.class, CharSequence.class)
+                                .entries(10)
                                 .averageValueSize(100)
                                 .replication(SingleChronicleHashReplication.builder()
                                         .tcpTransportAndNetwork(map2Config)
@@ -137,7 +139,7 @@ public class TCPSocketReplicationBootStrapTest {
         {
             // restart map 2 but does not connect it to map1
             final ChronicleMap<Integer, CharSequence> map2b = ChronicleMap
-                    .of(Integer.class, CharSequence.class).averageValueSize(100)
+                    .of(Integer.class, CharSequence.class)
                     .replication((byte) 2).createPersistedTo(persistenceFile);
             // add data into it
             map2b.put(11, "ADDED WHEN DISCONNECTED TO MAP1");
@@ -148,7 +150,6 @@ public class TCPSocketReplicationBootStrapTest {
         TcpTransportAndNetworkConfig tcpConfigNewMap2 = TcpTransportAndNetworkConfig.of(8067)
                 .heartBeatInterval(1L, TimeUnit.SECONDS);
         map2 = ChronicleMapBuilder.of(Integer.class, CharSequence.class)
-                .averageValueSize(100)
                 .replication(SingleChronicleHashReplication.builder()
                         .tcpTransportAndNetwork(tcpConfigNewMap2)
                         .name("newMap2")
diff --git a/src/test/java/net/openhft/chronicle/map/TCPSocketReplicationNativeTest.java b/src/test/java/net/openhft/chronicle/map/TCPSocketReplicationNativeTest.java
index 5aef105d9..1561ef123 100644
--- a/src/test/java/net/openhft/chronicle/map/TCPSocketReplicationNativeTest.java
+++ b/src/test/java/net/openhft/chronicle/map/TCPSocketReplicationNativeTest.java
@@ -49,14 +49,14 @@ public class TCPSocketReplicationNativeTest {
         TcpTransportAndNetworkConfig tcpConfig1 = TcpTransportAndNetworkConfig.of(8076, endpoint)
                 .heartBeatInterval(1L, TimeUnit.SECONDS).autoReconnectedUponDroppedConnection(true);
 
-        map1 = ChronicleMapBuilder.of(Integer.class, LongValue.class)
-                .replication((byte) 1, tcpConfig1).create();
+        map1 = ChronicleMap.of(Integer.class, LongValue.class)
+                .entries(10).replication((byte) 1, tcpConfig1).create();
 
         TcpTransportAndNetworkConfig tcpConfig2 = TcpTransportAndNetworkConfig.of(8077)
                 .heartBeatInterval(1L, TimeUnit.SECONDS).autoReconnectedUponDroppedConnection(true);
 
-        map2 = ChronicleMapBuilder.of(Integer.class, LongValue.class)
-                .replication((byte) 2, tcpConfig2).create();
+        map2 = ChronicleMap.of(Integer.class, LongValue.class)
+                .entries(10).replication((byte) 2, tcpConfig2).create();
     }
 
     @After
diff --git a/src/test/java/net/openhft/chronicle/map/TcpReplicationWithAcquireContextTest.java b/src/test/java/net/openhft/chronicle/map/TcpReplicationWithAcquireContextTest.java
index 8775fbb9d..048ba8e7c 100644
--- a/src/test/java/net/openhft/chronicle/map/TcpReplicationWithAcquireContextTest.java
+++ b/src/test/java/net/openhft/chronicle/map/TcpReplicationWithAcquireContextTest.java
@@ -40,6 +40,7 @@ public class TcpReplicationWithAcquireContextTest {
 
         try (ChronicleMap<CharSequence, TestInstrumentVOInterface> map1 = ChronicleMap
                 .of(CharSequence.class, TestInstrumentVOInterface.class)
+                .entries(1)
                 .averageKey("hello")
                 .replication((byte) 1, config1)
                 .create()) {
@@ -52,6 +53,7 @@ public class TcpReplicationWithAcquireContextTest {
 
             try (ChronicleMap<CharSequence, TestInstrumentVOInterface> map2 =
                          ChronicleMap.of(CharSequence.class, TestInstrumentVOInterface.class)
+                                 .entries(1)
                                  .averageKey("hello")
                                  .replication((byte) 2, config2)
                                  .create()) {
diff --git a/src/test/java/net/openhft/chronicle/map/TestReplication.java b/src/test/java/net/openhft/chronicle/map/TestReplication.java
index 5b8452b7f..2192dd13d 100644
--- a/src/test/java/net/openhft/chronicle/map/TestReplication.java
+++ b/src/test/java/net/openhft/chronicle/map/TestReplication.java
@@ -38,12 +38,12 @@ public class TestReplication {
                 TcpTransportAndNetworkConfig.of(8098, new InetSocketAddress("localhost",
                         8097));
 
-        try (ChronicleMap<Integer, Integer> map2 = ChronicleMapBuilder
-                .of(Integer.class, Integer.class)
+        try (ChronicleMap<Integer, Integer> map2 = ChronicleMap.of(Integer.class, Integer.class)
+                .entries(70000)
                 .replication((byte) 2, tcpConfigServer2)
                 .create();
-             ChronicleMap<Integer, Integer> map1 = ChronicleMapBuilder
-                     .of(Integer.class, Integer.class)
+             ChronicleMap<Integer, Integer> map1 = ChronicleMap.of(Integer.class, Integer.class)
+                     .entries(70000)
                      .replication((byte) 3, tcpConfigServer1)
                      .create()) {
 
@@ -78,15 +78,15 @@ public class TestReplication {
             final File tempFile = File.createTempFile("test", "chron");
 
 
-            server1 = ChronicleMapBuilder.of(String.class, String.class)
+            server1 = ChronicleMap.of(String.class, String.class)
+                    .entries(1)
                     .averageKey("key").averageValue("value")
                     .replication((byte) 1).createPersistedTo(tempFile);
 
             TcpTransportAndNetworkConfig serverConfig = TcpTransportAndNetworkConfig.of(9000);
 
             // user for replication only
-            forServer1Replication = ChronicleMapBuilder.of(String.class, String.class)
-                    .averageKey("key").averageValue("value")
+            forServer1Replication = ChronicleMap.of(String.class, String.class)
                     .replication((byte) 1, serverConfig).createPersistedTo(tempFile);
 
         }
@@ -98,6 +98,7 @@ public class TestReplication {
                     InetSocketAddress("localhost", 9000));
 
             server2 = ChronicleMapBuilder.of(String.class, String.class)
+                    .entries(1)
                     .averageKey("key").averageValue("value")
                     .replication((byte) 2, server2Config).create();
 
diff --git a/src/test/java/net/openhft/chronicle/set/ChronicleSetBuilderTest.java b/src/test/java/net/openhft/chronicle/set/ChronicleSetBuilderTest.java
index 1b9a21074..6d3d51a7c 100644
--- a/src/test/java/net/openhft/chronicle/set/ChronicleSetBuilderTest.java
+++ b/src/test/java/net/openhft/chronicle/set/ChronicleSetBuilderTest.java
@@ -24,7 +24,7 @@ public class ChronicleSetBuilderTest {
     @Test
     public void test() {
 
-        try (ChronicleSet<Integer> integers = ChronicleSetBuilder.of(Integer.class).create()) {
+        try (ChronicleSet<Integer> integers = ChronicleSet.of(Integer.class).entries(10).create()) {
             for (int i = 0; i < 10; i++) {
                 integers.add(i);
             }
diff --git a/src/test/java/net/openhft/chronicle/set/SetForTCPSocketReplication3wayTest.java b/src/test/java/net/openhft/chronicle/set/SetForTCPSocketReplication3wayTest.java
index 6d029ba1e..d99518ddc 100644
--- a/src/test/java/net/openhft/chronicle/set/SetForTCPSocketReplication3wayTest.java
+++ b/src/test/java/net/openhft/chronicle/set/SetForTCPSocketReplication3wayTest.java
@@ -46,7 +46,8 @@ public class SetForTCPSocketReplication3wayTest {
             final byte identifier,
             final int serverPort,
             final InetSocketAddress... endpoints) throws IOException {
-        return (T) ChronicleSetBuilder.of(Integer.class)
+        return (T) ChronicleSet.of(Integer.class)
+                .entries(10)
                 .replication(identifier, TcpTransportAndNetworkConfig.of(serverPort, asList(endpoints))
                         .heartBeatInterval(1L, SECONDS).autoReconnectedUponDroppedConnection(true))
                 .createPersistedTo(getPersistenceFile());
diff --git a/src/test/java/net/openhft/lang/values/DoubleArrayTest.java b/src/test/java/net/openhft/lang/values/DoubleArrayTest.java
index 61560aca7..f3978b1b6 100755
--- a/src/test/java/net/openhft/lang/values/DoubleArrayTest.java
+++ b/src/test/java/net/openhft/lang/values/DoubleArrayTest.java
@@ -73,7 +73,9 @@ public class DoubleArrayTest {
         DoubleArray b = new DoubleArray(10);
         b.setData(new double[]{5, 6, 7, 8, 9});
 
-        ChronicleMap<Integer, DoubleArray> proxyMap = ChronicleMapBuilder.of(Integer.class, DoubleArray.class)
+        ChronicleMap<Integer, DoubleArray> proxyMap = ChronicleMap
+                .of(Integer.class, DoubleArray.class)
+                .entries(2)
                 .create();
         proxyMap.put(1, a);
         proxyMap.put(2, b);