diff --git a/builder/src/main/java/net/kemitix/checkstyle/ruleset/builder/DefaultReadmeIndexBuilder.java b/builder/src/main/java/net/kemitix/checkstyle/ruleset/builder/DefaultReadmeIndexBuilder.java
new file mode 100644
index 0000000..1c018f6
--- /dev/null
+++ b/builder/src/main/java/net/kemitix/checkstyle/ruleset/builder/DefaultReadmeIndexBuilder.java
@@ -0,0 +1,78 @@
+package net.kemitix.checkstyle.ruleset.builder;
+
+import lombok.RequiredArgsConstructor;
+import org.springframework.stereotype.Component;
+
+import java.util.Comparator;
+import java.util.Locale;
+import java.util.Optional;
+import java.util.function.Function;
+import java.util.stream.Collectors;
+
+/**
+ * Default Rule Index Builder.
+ *
+ * @author Paul Campbell (paul.campbell@hubio.com)
+ */
+@Component
+@RequiredArgsConstructor
+public class DefaultReadmeIndexBuilder implements ReadmeIndexBuilder {
+
+    private static final String NEWLINE = "\n";
+
+    private static final String HEADERROW = "Rule|Level|Source|Enabled|Suppressable\n";
+
+    private static final String SEPARATOR = "----|-----|------|-------|------------\n";
+
+    private static final Locale LOCALE = Locale.ENGLISH;
+
+    private final RulesProperties rulesProperties;
+
+    @Override
+    public String build() {
+        return HEADERROW + SEPARATOR + rulesProperties.getRules()
+                                                      .stream()
+                                                      .sorted(Comparator.comparing(lowerCaseRuleName()))
+                                                      .map(this::formatRuleRow)
+                                                      .collect(Collectors.joining(NEWLINE));
+    }
+
+    private Function<Rule, String> lowerCaseRuleName() {
+        return this::getLowerCaseRuleName;
+    }
+
+    private String getLowerCaseRuleName(final Rule rule) {
+        return rule.getName()
+                   .toLowerCase(LOCALE);
+    }
+
+    private String formatRuleRow(final Rule rule) {
+        return String.format(
+                "%s|%s|%s|%s|%s", link(rule), level(rule), source(rule), enabled(rule), suppressible(rule));
+    }
+
+    private String suppressible(final Rule rule) {
+        return rule.isInsuppressible() ? "No" : "";
+    }
+
+    private String enabled(final Rule rule) {
+        return rule.isEnabled() ? "Yes" : "";
+    }
+
+    private String source(final Rule rule) {
+        return rule.getSource()
+                   .toString()
+                   .toLowerCase(LOCALE);
+    }
+
+    private String link(final Rule rule) {
+        return String.format("[%s](#%s)", rule.getName(), getLowerCaseRuleName(rule));
+    }
+
+    private String level(final Rule rule) {
+        return Optional.ofNullable(rule.getLevel())
+                       .orElse(RuleLevel.UNSPECIFIED)
+                       .toString()
+                       .toLowerCase(LOCALE);
+    }
+}
diff --git a/builder/src/main/java/net/kemitix/checkstyle/ruleset/builder/ReadmeIndexBuilder.java b/builder/src/main/java/net/kemitix/checkstyle/ruleset/builder/ReadmeIndexBuilder.java
new file mode 100644
index 0000000..004cccd
--- /dev/null
+++ b/builder/src/main/java/net/kemitix/checkstyle/ruleset/builder/ReadmeIndexBuilder.java
@@ -0,0 +1,16 @@
+package net.kemitix.checkstyle.ruleset.builder;
+
+/**
+ * Creates the Rule Index for README.md in Markdown Format.
+ *
+ * @author Paul Campbell (paul.campbell@hubio.com)
+ */
+public interface ReadmeIndexBuilder {
+
+    /**
+     * Builds the Rule Index in Markdown Format.
+     *
+     * @return The rule index.
+     */
+    String build();
+}
diff --git a/builder/src/main/java/net/kemitix/checkstyle/ruleset/builder/ReadmeWriter.java b/builder/src/main/java/net/kemitix/checkstyle/ruleset/builder/ReadmeWriter.java
index 4a4a273..673f313 100644
--- a/builder/src/main/java/net/kemitix/checkstyle/ruleset/builder/ReadmeWriter.java
+++ b/builder/src/main/java/net/kemitix/checkstyle/ruleset/builder/ReadmeWriter.java
@@ -33,9 +33,6 @@ import java.nio.charset.StandardCharsets;
 import java.nio.file.Files;
 import java.nio.file.Path;
 import java.nio.file.StandardOpenOption;
-import java.util.Comparator;
-import java.util.Locale;
-import java.util.Optional;
 import java.util.function.Predicate;
 import java.util.stream.Collectors;
 
@@ -58,48 +55,23 @@ class ReadmeWriter implements CommandLineRunner {
 
     private final RuleReadmeLoader ruleReadmeLoader;
 
+    private final ReadmeIndexBuilder indexBuilder;
+
     @Override
     public void run(final String... args) throws Exception {
         final String readmeTemplate = readFile(templateProperties.getReadmeTemplate());
-        final String indexHeader =
-                "Rule|Level|Source|Enabled|Suppressable\n" + "----|-----|------|-------|------------\n";
-        final String index = ruleIndex();
         final String enabledCheckstyle = readmeRules(this::isEnabledCheckstyleRule);
         final String enabledSevntu = readmeRules(this::isEnabledSevntuRule);
         final String disabledCheckstyle = readmeRules(this::isDisabledCheckstyleRule);
         final String disabledSevntu = readmeRules(this::isDisabledSevntuRule);
         final byte[] readme =
-                String.format(readmeTemplate, indexHeader + index, enabledCheckstyle, enabledSevntu, disabledCheckstyle,
+                String.format(readmeTemplate, indexBuilder.build(), enabledCheckstyle, enabledSevntu, disabledCheckstyle,
                               disabledSevntu
                              )
                       .getBytes(StandardCharsets.UTF_8);
         Files.write(outputProperties.getReadme(), readme, StandardOpenOption.TRUNCATE_EXISTING);
     }
 
-    private String ruleIndex() {
-        return rulesProperties.getRules()
-                              .stream()
-                              .sorted(Comparator.comparing(rule -> rule.getName()
-                                                                       .toLowerCase(Locale.ENGLISH)))
-                              .map(this::formatRuleIndex)
-                              .collect(Collectors.joining(NEWLINE));
-    }
-
-    private String formatRuleIndex(final Rule rule) {
-        final String ruleLink = rule.getName()
-                                    .toLowerCase(Locale.ENGLISH);
-        final String level = Optional.ofNullable(rule.getLevel())
-                                     .orElse(RuleLevel.UNSPECIFIED)
-                                     .toString()
-                                     .toLowerCase(Locale.ENGLISH);
-        final String source = rule.getSource()
-                                  .toString()
-                                  .toLowerCase(Locale.ENGLISH);
-        final String enabled = rule.isEnabled() ? "Yes" : "";
-        final String insuppressible = rule.isInsuppressible() ? "No" : "";
-        return String.format("[%s](#%s)|%s|%s|%s|%s", rule.getName(), ruleLink, level, source, enabled, insuppressible);
-    }
-
     private boolean isEnabledSevntuRule(final Rule rule) {
         return rule.isEnabled() && RuleSource.SEVNTU.equals(rule.getSource());
     }