diff --git a/codecov.yml b/codecov.yml
new file mode 100644
index 0000000..76fbf04
--- /dev/null
+++ b/codecov.yml
@@ -0,0 +1,6 @@
+coverage:
+  status:
+    project:
+      default:
+        # basic
+        target: 100%
\ No newline at end of file
diff --git a/src/main/java/se/cygni/palmithor/tdd/StringUtils.java b/src/main/java/se/cygni/palmithor/tdd/StringUtils.java
index 3b36d6b..2b27b72 100644
--- a/src/main/java/se/cygni/palmithor/tdd/StringUtils.java
+++ b/src/main/java/se/cygni/palmithor/tdd/StringUtils.java
@@ -4,7 +4,12 @@ public class StringUtils {
 
 
     public boolean isPalindrome(final String str) {
-        throw new RuntimeException("Not yet implemented");
+        if (str == null) {
+            return false;
+        }
+        String revStr = new StringBuilder(str).reverse().toString();
+        return str.equals(revStr);
+
     }
 
 
@@ -15,6 +20,6 @@ public boolean isPalindrome(final String str) {
      * @return true if str is null, empty or whitespace only, otherwise false
      */
     public boolean isBlank(final String str) {
-        throw new RuntimeException("Not yet implemented");
+        return str == null || str.trim().isEmpty();
     }
 }
diff --git a/src/test/java/se/cygni/palmithor/tdd/CalculatorTest.java b/src/test/java/se/cygni/palmithor/tdd/CalculatorTest.java
index ed4264e..013a3c0 100644
--- a/src/test/java/se/cygni/palmithor/tdd/CalculatorTest.java
+++ b/src/test/java/se/cygni/palmithor/tdd/CalculatorTest.java
@@ -3,6 +3,7 @@
 
 import org.junit.Test;
 
+import java.util.Arrays;
 import java.util.Optional;
 
 import static org.assertj.core.api.Assertions.assertThat;
@@ -13,8 +14,10 @@ public class CalculatorTest {
 
     @Test
     public void test() {
-        //assertThat(calculator.sumAll().get()).isEqualTo(1); // fail un purpose
-    }
-
 
+        assertThat(calculator.sumAll(null).isPresent()).isFalse();
+        assertThat(calculator.sumAll(new Integer[0]).get()).isEqualTo(0);
+        assertThat(calculator.sumAll(1,2).get()).isEqualTo(3);
+        assertThat(calculator.sumAll(1,2,3,4).get()).isEqualTo(10);
+    }
 }
\ No newline at end of file
diff --git a/src/test/java/se/cygni/palmithor/tdd/StringUtilsTest.java b/src/test/java/se/cygni/palmithor/tdd/StringUtilsTest.java
index 09cabc4..856f939 100644
--- a/src/test/java/se/cygni/palmithor/tdd/StringUtilsTest.java
+++ b/src/test/java/se/cygni/palmithor/tdd/StringUtilsTest.java
@@ -11,14 +11,12 @@ public class StringUtilsTest {
 
     @Test
     public void isPalindrome() {
-        /*
         assertThat(stringUtils.isPalindrome("aabb")).isFalse();
         assertThat(stringUtils.isPalindrome(null)).isFalse();
         assertThat(stringUtils.isPalindrome("NotEvenClose")).isFalse();
         assertThat(stringUtils.isPalindrome("")).isTrue();
         assertThat(stringUtils.isPalindrome("abba")).isTrue();
         assertThat(stringUtils.isPalindrome("tattarrattat")).isTrue();
-        */
     }
 
     /**
@@ -26,6 +24,10 @@ public void isPalindrome() {
      */
     @Test
     public void isBlank() {
-        // stringUtils.isBlank()
+        assertThat(stringUtils.isBlank(null)).isTrue();
+        assertThat(stringUtils.isBlank("")).isTrue();
+        assertThat(stringUtils.isBlank(" ")).isTrue();
+        assertThat(stringUtils.isBlank("  \n     ")).isTrue();
+        assertThat(stringUtils.isBlank("This is sparta!!")).isFalse();
     }
 }
\ No newline at end of file