diff --git a/app-sample/src/main/java/io/noties/markwon/app/samples/editor/EditorHeadingSample.java b/app-sample/src/main/java/io/noties/markwon/app/samples/editor/EditorHeadingSample.java
index 915343f5..492d6a80 100644
--- a/app-sample/src/main/java/io/noties/markwon/app/samples/editor/EditorHeadingSample.java
+++ b/app-sample/src/main/java/io/noties/markwon/app/samples/editor/EditorHeadingSample.java
@@ -5,7 +5,7 @@ import java.util.concurrent.Executors;
 import io.noties.markwon.Markwon;
 import io.noties.markwon.app.sample.Tags;
 import io.noties.markwon.app.samples.editor.shared.MarkwonEditTextSample;
-import io.noties.markwon.app.samples.editor.shared.HeadingEditHandler;
+import io.noties.markwon.editor.handler.HeadingEditHandler;
 import io.noties.markwon.editor.MarkwonEditor;
 import io.noties.markwon.editor.MarkwonEditorTextWatcher;
 import io.noties.markwon.sample.annotations.MarkwonArtifact;
diff --git a/app-sample/src/main/java/io/noties/markwon/app/samples/editor/WYSIWYGEditorSample.java b/app-sample/src/main/java/io/noties/markwon/app/samples/editor/WYSIWYGEditorSample.java
index 01f916d8..0c36c870 100644
--- a/app-sample/src/main/java/io/noties/markwon/app/samples/editor/WYSIWYGEditorSample.java
+++ b/app-sample/src/main/java/io/noties/markwon/app/samples/editor/WYSIWYGEditorSample.java
@@ -15,7 +15,6 @@ import io.noties.markwon.SoftBreakAddsNewLinePlugin;
 import io.noties.markwon.app.sample.Tags;
 import io.noties.markwon.app.samples.editor.shared.BlockQuoteEditHandler;
 import io.noties.markwon.app.samples.editor.shared.CodeEditHandler;
-import io.noties.markwon.app.samples.editor.shared.HeadingEditHandler;
 import io.noties.markwon.app.samples.editor.shared.LinkEditHandler;
 import io.noties.markwon.app.samples.editor.shared.MarkwonEditTextSample;
 import io.noties.markwon.app.samples.editor.shared.StrikethroughEditHandler;
@@ -23,6 +22,7 @@ import io.noties.markwon.editor.MarkwonEditor;
 import io.noties.markwon.editor.MarkwonEditorTextWatcher;
 import io.noties.markwon.editor.PersistedSpans;
 import io.noties.markwon.editor.handler.EmphasisEditHandler;
+import io.noties.markwon.editor.handler.HeadingEditHandler;
 import io.noties.markwon.editor.handler.StrongEmphasisEditHandler;
 import io.noties.markwon.sample.annotations.MarkwonArtifact;
 import io.noties.markwon.sample.annotations.MarkwonSampleInfo;
diff --git a/markwon-editor/build.gradle b/markwon-editor/build.gradle
index 884f6fb6..393759ba 100644
--- a/markwon-editor/build.gradle
+++ b/markwon-editor/build.gradle
@@ -11,6 +11,11 @@ android {
         versionCode 1
         versionName version
     }
+
+    compileOptions {
+        targetCompatibility JavaVersion.VERSION_1_8
+        sourceCompatibility JavaVersion.VERSION_1_8
+    }
 }
 
 dependencies {
diff --git a/markwon-editor/src/main/java/io/noties/markwon/editor/handler/HeadingEditHandler.java b/markwon-editor/src/main/java/io/noties/markwon/editor/handler/HeadingEditHandler.java
index 70652bbc..ce4b5b25 100644
--- a/markwon-editor/src/main/java/io/noties/markwon/editor/handler/HeadingEditHandler.java
+++ b/markwon-editor/src/main/java/io/noties/markwon/editor/handler/HeadingEditHandler.java
@@ -1,4 +1,4 @@
-package it.niedermann.android.markdown.markwon.handler;
+package io.noties.markwon.editor.handler;
 
 import android.text.Editable;
 import android.text.Spanned;
@@ -13,7 +13,6 @@ import io.noties.markwon.editor.PersistedSpans;
 
 public class HeadingEditHandler implements EditHandler<HeadingSpan> {
 
-
   private MarkwonTheme theme;
 
   @Override
@@ -23,12 +22,12 @@ public class HeadingEditHandler implements EditHandler<HeadingSpan> {
 
   @Override
   public void configurePersistedSpans(@NonNull PersistedSpans.Builder builder) {
-    builder.persistSpan(Heading1Span.class, new Runnable() { new Heading1Span(theme);});
-    builder.persistSpan(Heading2Span.class, new Runnable() { new Heading2Span(theme);});
-    builder.persistSpan(Heading3Span.class, new Runnable() { new Heading3Span(theme);});
-    builder.persistSpan(Heading4Span.class, new Runnable() { new Heading4Span(theme);});
-    builder.persistSpan(Heading5Span.class, new Runnable() { new Heading5Span(theme);});
-    builder.persistSpan(Heading6Span.class, new Runnable() { new Heading6Span(theme);});
+    builder.persistSpan(Heading1Span.class, () -> new Heading1Span(theme));
+    builder.persistSpan(Heading2Span.class, () -> new Heading2Span(theme));
+    builder.persistSpan(Heading3Span.class, () -> new Heading3Span(theme));
+    builder.persistSpan(Heading4Span.class, () -> new Heading4Span(theme));
+    builder.persistSpan(Heading5Span.class, () -> new Heading5Span(theme));
+    builder.persistSpan(Heading6Span.class, () -> new Heading6Span(theme));
   }
 
   @Override
@@ -39,7 +38,7 @@ public class HeadingEditHandler implements EditHandler<HeadingSpan> {
           @NonNull HeadingSpan span,
           int spanStart,
           int spanTextLength) {
-    HeadingSpan newSpan;
+    final HeadingSpan newSpan;
 
     switch (span.getLevel()) {
       case 1:
@@ -64,8 +63,8 @@ public class HeadingEditHandler implements EditHandler<HeadingSpan> {
         return;
 
     }
-    int newStart = getNewSpanStart(input, spanStart);
-    int newEnd = findEnd(input, newStart, newSpan.getLevel());
+    final int newStart = getNewSpanStart(input, spanStart);
+    final int newEnd = findEnd(input, newStart, newSpan.getLevel());
 
     editable.setSpan(
             newSpan,
@@ -77,24 +76,24 @@ public class HeadingEditHandler implements EditHandler<HeadingSpan> {
 
   private int findEnd(String input, int searchFrom, int spanLevel) {
     int end = searchFrom + spanLevel;
-    int strLength = input.length();
-    while (end < strLength-1) {
+    final int strLength = input.length();
+    while (end < strLength - 1) {
       end++;
       if (input.charAt(end) == '\n') {
         break;
       }
     }
-    return end+1;
+    return end + 1;
   }
 
   private int getNewSpanStart(String input, int spanStart) {
-
     int start = spanStart;
 
     while (start >= 0 && input.charAt(start) != '\n') {
       start--;
     }
     start += 1;
+
     return start;
   }