diff --git a/observable-cache-1/src/main/java/com/github/aleksandermielczarek/observablecache/CompletableFromCache.java b/observable-cache-1/src/main/java/com/github/aleksandermielczarek/observablecache/CompletableFromCache.java
index ad7d9ec..b9c49bb 100644
--- a/observable-cache-1/src/main/java/com/github/aleksandermielczarek/observablecache/CompletableFromCache.java
+++ b/observable-cache-1/src/main/java/com/github/aleksandermielczarek/observablecache/CompletableFromCache.java
@@ -11,12 +11,16 @@
  */
 public final class CompletableFromCache extends ValueFromCache<Completable> {
 
-    CompletableFromCache(@Nullable Completable valueFromCache) {
+    public CompletableFromCache() {
+        this(null);
+    }
+
+    public CompletableFromCache(@Nullable Completable valueFromCache) {
         super(valueFromCache);
     }
 
     public static CompletableFromCache empty() {
-        return new CompletableFromCache(null);
+        return new CompletableFromCache();
     }
 
     public static CompletableFromCache of(@Nullable Completable valueFromCache) {
diff --git a/observable-cache-1/src/main/java/com/github/aleksandermielczarek/observablecache/ObservableFromCache.java b/observable-cache-1/src/main/java/com/github/aleksandermielczarek/observablecache/ObservableFromCache.java
index 8e6a156..295ec5a 100644
--- a/observable-cache-1/src/main/java/com/github/aleksandermielczarek/observablecache/ObservableFromCache.java
+++ b/observable-cache-1/src/main/java/com/github/aleksandermielczarek/observablecache/ObservableFromCache.java
@@ -11,12 +11,16 @@
  */
 public final class ObservableFromCache<T> extends ValueFromCache<Observable<T>> {
 
-    ObservableFromCache(@Nullable Observable<T> valueFromCache) {
+    public ObservableFromCache() {
+        this(null);
+    }
+
+    public ObservableFromCache(@Nullable Observable<T> valueFromCache) {
         super(valueFromCache);
     }
 
     public static <T> ObservableFromCache<T> empty() {
-        return new ObservableFromCache<>(null);
+        return new ObservableFromCache<>();
     }
 
     public static <T> ObservableFromCache<T> of(@Nullable Observable<T> valueFromCache) {
diff --git a/observable-cache-1/src/main/java/com/github/aleksandermielczarek/observablecache/SingleFromCache.java b/observable-cache-1/src/main/java/com/github/aleksandermielczarek/observablecache/SingleFromCache.java
index 596ede0..73c3599 100644
--- a/observable-cache-1/src/main/java/com/github/aleksandermielczarek/observablecache/SingleFromCache.java
+++ b/observable-cache-1/src/main/java/com/github/aleksandermielczarek/observablecache/SingleFromCache.java
@@ -11,12 +11,16 @@
  */
 public final class SingleFromCache<T> extends ValueFromCache<Single<T>> {
 
-    SingleFromCache(@Nullable Single<T> valueFromCache) {
+    public SingleFromCache() {
+        this(null);
+    }
+
+    public SingleFromCache(@Nullable Single<T> valueFromCache) {
         super(valueFromCache);
     }
 
     public static <T> SingleFromCache<T> empty() {
-        return new SingleFromCache<>(null);
+        return new SingleFromCache<>();
     }
 
     public static <T> SingleFromCache<T> of(@Nullable Single<T> valueFromCache) {
diff --git a/observable-cache-2/src/main/java/com/github/aleksandermielczarek/observablecache2/CompletableFromCache.java b/observable-cache-2/src/main/java/com/github/aleksandermielczarek/observablecache2/CompletableFromCache.java
index 352bb1b..08d63f5 100644
--- a/observable-cache-2/src/main/java/com/github/aleksandermielczarek/observablecache2/CompletableFromCache.java
+++ b/observable-cache-2/src/main/java/com/github/aleksandermielczarek/observablecache2/CompletableFromCache.java
@@ -12,12 +12,16 @@
 
 public final class CompletableFromCache extends ValueFromCache<Completable> {
 
-    CompletableFromCache(@Nullable Completable valueFromCache) {
+    public CompletableFromCache() {
+        this(null);
+    }
+
+    public CompletableFromCache(@Nullable Completable valueFromCache) {
         super(valueFromCache);
     }
 
     public static CompletableFromCache empty() {
-        return new CompletableFromCache(null);
+        return new CompletableFromCache();
     }
 
     public static CompletableFromCache of(@Nullable Completable valueFromCache) {
diff --git a/observable-cache-2/src/main/java/com/github/aleksandermielczarek/observablecache2/FlowableFromCache.java b/observable-cache-2/src/main/java/com/github/aleksandermielczarek/observablecache2/FlowableFromCache.java
index d5a2f0d..3774d55 100644
--- a/observable-cache-2/src/main/java/com/github/aleksandermielczarek/observablecache2/FlowableFromCache.java
+++ b/observable-cache-2/src/main/java/com/github/aleksandermielczarek/observablecache2/FlowableFromCache.java
@@ -12,12 +12,16 @@
 
 public final class FlowableFromCache<T> extends ValueFromCache<Flowable<T>> {
 
-    FlowableFromCache(@Nullable Flowable<T> valueFromCache) {
+    public FlowableFromCache() {
+        this(null);
+    }
+
+    public FlowableFromCache(@Nullable Flowable<T> valueFromCache) {
         super(valueFromCache);
     }
 
     public static <T> FlowableFromCache<T> empty() {
-        return new FlowableFromCache<>(null);
+        return new FlowableFromCache<>();
     }
 
     public static <T> FlowableFromCache<T> of(@Nullable Flowable<T> valueFromCache) {
diff --git a/observable-cache-2/src/main/java/com/github/aleksandermielczarek/observablecache2/MaybeFromCache.java b/observable-cache-2/src/main/java/com/github/aleksandermielczarek/observablecache2/MaybeFromCache.java
index 97afa94..fa92a74 100644
--- a/observable-cache-2/src/main/java/com/github/aleksandermielczarek/observablecache2/MaybeFromCache.java
+++ b/observable-cache-2/src/main/java/com/github/aleksandermielczarek/observablecache2/MaybeFromCache.java
@@ -12,12 +12,16 @@
 
 public final class MaybeFromCache<T> extends ValueFromCache<Maybe<T>> {
 
-    MaybeFromCache(@Nullable Maybe<T> valueFromCache) {
+    public MaybeFromCache() {
+        this(null);
+    }
+
+    public MaybeFromCache(@Nullable Maybe<T> valueFromCache) {
         super(valueFromCache);
     }
 
     public static <T> MaybeFromCache<T> empty() {
-        return new MaybeFromCache<>(null);
+        return new MaybeFromCache<>();
     }
 
     public static <T> MaybeFromCache<T> of(@Nullable Maybe<T> valueFromCache) {
diff --git a/observable-cache-2/src/main/java/com/github/aleksandermielczarek/observablecache2/ObservableFromCache.java b/observable-cache-2/src/main/java/com/github/aleksandermielczarek/observablecache2/ObservableFromCache.java
index e3304cc..9943c52 100644
--- a/observable-cache-2/src/main/java/com/github/aleksandermielczarek/observablecache2/ObservableFromCache.java
+++ b/observable-cache-2/src/main/java/com/github/aleksandermielczarek/observablecache2/ObservableFromCache.java
@@ -12,12 +12,16 @@
 
 public final class ObservableFromCache<T> extends ValueFromCache<Observable<T>> {
 
-    ObservableFromCache(@Nullable Observable<T> valueFromCache) {
+    public ObservableFromCache() {
+        this(null);
+    }
+
+    public ObservableFromCache(@Nullable Observable<T> valueFromCache) {
         super(valueFromCache);
     }
 
     public static <T> ObservableFromCache<T> empty() {
-        return new ObservableFromCache<>(null);
+        return new ObservableFromCache<>();
     }
 
     public static <T> ObservableFromCache<T> of(@Nullable Observable<T> valueFromCache) {
diff --git a/observable-cache-2/src/main/java/com/github/aleksandermielczarek/observablecache2/SingleFromCache.java b/observable-cache-2/src/main/java/com/github/aleksandermielczarek/observablecache2/SingleFromCache.java
index cb7cf4b..5d78b91 100644
--- a/observable-cache-2/src/main/java/com/github/aleksandermielczarek/observablecache2/SingleFromCache.java
+++ b/observable-cache-2/src/main/java/com/github/aleksandermielczarek/observablecache2/SingleFromCache.java
@@ -12,12 +12,16 @@
 
 public final class SingleFromCache<T> extends ValueFromCache<Single<T>> {
 
-    SingleFromCache(@Nullable Single<T> valueFromCache) {
+    public SingleFromCache() {
+        this(null);
+    }
+
+    public SingleFromCache(@Nullable Single<T> valueFromCache) {
         super(valueFromCache);
     }
 
     public static <T> SingleFromCache<T> empty() {
-        return new SingleFromCache<>(null);
+        return new SingleFromCache<>();
     }
 
     public static <T> SingleFromCache<T> of(@Nullable Single<T> valueFromCache) {
diff --git a/observable-cache-api/src/main/java/com/github/aleksandermielczarek/observablecache/api/ValueFromCache.java b/observable-cache-api/src/main/java/com/github/aleksandermielczarek/observablecache/api/ValueFromCache.java
index 33a69af..8267dd5 100644
--- a/observable-cache-api/src/main/java/com/github/aleksandermielczarek/observablecache/api/ValueFromCache.java
+++ b/observable-cache-api/src/main/java/com/github/aleksandermielczarek/observablecache/api/ValueFromCache.java
@@ -11,7 +11,7 @@ public abstract class ValueFromCache<T> {
     @Nullable
     private final T valueFromCache;
 
-    protected ValueFromCache(@Nullable T valueFromCache) {
+    public ValueFromCache(@Nullable T valueFromCache) {
         this.valueFromCache = valueFromCache;
     }