diff --git a/liquidjava-verifier/pom.xml b/liquidjava-verifier/pom.xml
index 5b42f4cb..673b0b5f 100644
--- a/liquidjava-verifier/pom.xml
+++ b/liquidjava-verifier/pom.xml
@@ -39,6 +39,45 @@
 				</configuration>
 			</plugin>
 			<plugin>
+<groupId>org.jacoco</groupId>
+<artifactId>jacoco-maven-plugin</artifactId>
+<version>0.8.14</version>
+<executions>
+<execution>
+<id>default-prepare-agent</id>
+<goals>
+<goal>prepare-agent</goal>
+</goals>
+</execution>
+<execution>
+<id>default-report</id>
+<goals>
+<goal>report</goal>
+</goals>
+</execution>
+<execution>
+<id>default-check</id>
+<goals>
+<goal>check</goal>
+</goals>
+<configuration>
+<rules>
+<rule>
+<element>BUNDLE</element>
+<limits>
+<limit>
+<counter>COMPLEXITY</counter>
+<value>COVEREDRATIO</value>
+<minimum>0.60</minimum>
+</limit>
+</limits>
+</rule>
+</rules>
+</configuration>
+</execution>
+</executions>
+</plugin>
+			<plugin>
 				<groupId>org.apache.maven.plugins</groupId>
 				<artifactId>maven-compiler-plugin</artifactId>
 				<version>${pVersion.compiler}</version>
diff --git a/liquidjava-verifier/src/test/java/liquidjava/rj_language/TestLiteralString.java b/liquidjava-verifier/src/test/java/liquidjava/rj_language/TestLiteralString.java
new file mode 100644
index 00000000..341ce079
--- /dev/null
+++ b/liquidjava-verifier/src/test/java/liquidjava/rj_language/TestLiteralString.java
@@ -0,0 +1,15 @@
+
+package liquidjava.rj_language;
+
+import static org.junit.Assert.assertNotEquals;
+import org.junit.Test;
+import liquidjava.rj_language.ast.LiteralString;
+
+public class TestLiteralString {
+    @Test
+    public void testLiteralString() {
+        LiteralString s1 = new LiteralString("hello");
+        LiteralString s2 = new LiteralString("world");
+        assertNotEquals(s1.hashCode(), s2.hashCode());
+    }
+}
diff --git a/liquidjava-verifier/src/test/java/liquidjava/rj_language/opt/TestOptimization.java b/liquidjava-verifier/src/test/java/liquidjava/rj_language/opt/TestOptimization.java
new file mode 100644
index 00000000..cdf819a8
--- /dev/null
+++ b/liquidjava-verifier/src/test/java/liquidjava/rj_language/opt/TestOptimization.java
@@ -0,0 +1,18 @@
+import static org.junit.Assert.assertEquals;
+
+import org.junit.Test;
+
+import liquidjava.rj_language.ast.BinaryExpression;
+import liquidjava.rj_language.ast.LiteralInt;
+import liquidjava.rj_language.opt.ConstantFolding;
+import liquidjava.rj_language.opt.derivation_node.ValDerivationNode;
+
+public class TestOptimization {
+    @Test
+    public void testBinaryFold() {
+        BinaryExpression b = new BinaryExpression(new LiteralInt(1), "+", new LiteralInt(2));
+
+        ValDerivationNode r = ConstantFolding.fold(new ValDerivationNode(b, null));
+        assertEquals(r.getValue(), new LiteralInt(3));
+    }
+}
diff --git a/liquidjava-verifier/src/test/java/liquidjava/rj_language/opt/TesteIntegracao.java b/liquidjava-verifier/src/test/java/liquidjava/rj_language/opt/TesteIntegracao.java
new file mode 100644
index 00000000..eb156065
--- /dev/null
+++ b/liquidjava-verifier/src/test/java/liquidjava/rj_language/opt/TesteIntegracao.java
@@ -0,0 +1,28 @@
+package liquidjava.integration;
+
+import liquidjava.errors.ErrorEmitter;
+import org.junit.jupiter.api.Test;
+import static org.junit.jupiter.api.Assertions.*;
+
+/**
+ * Simple integration test that verifies interaction between the ErrorEmitter class and the simulated error reporting
+ * process.
+ */
+public class TesteIntegracao {
+
+    @Test
+    void shouldEmitAndRetrieveErrorInfo() {
+        ErrorEmitter emitter = new ErrorEmitter();
+
+        emitter.addError("Integration test error", "FakeFile.java", 42);
+
+        assertTrue(emitter.foundError(), "Emitter should register an error");
+        assertNotNull(emitter.getFullMessage(), "Full message should not be null");
+
+        try {
+            emitter.getFilePath();
+        } catch (Exception e) {
+            fail("getFilePath() should not throw an exception");
+        }
+    }
+}
diff --git a/liquidjava-verifier/src/test/java/liquidjava/rj_language/opt/TestesErrorEmitter.java b/liquidjava-verifier/src/test/java/liquidjava/rj_language/opt/TestesErrorEmitter.java
new file mode 100644
index 00000000..c690fa84
--- /dev/null
+++ b/liquidjava-verifier/src/test/java/liquidjava/rj_language/opt/TestesErrorEmitter.java
@@ -0,0 +1,41 @@
+package liquidjava.errors;
+
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import static org.junit.jupiter.api.Assertions.*;
+
+public class TestesErrorEmitter {
+
+    private ErrorEmitter emitter;
+
+    /**
+     * Initializes a new ErrorEmitter before each test.
+     */
+
+    @BeforeEach
+    void setup() {
+        emitter = new ErrorEmitter();
+    }
+
+    /**
+     * Tests that all getter methods return non-null values after an error is added.
+     */
+
+    @Test
+    void returnNonNullValues() {
+        emitter.addError("test", "main.java", 1);
+        assertNotNull(emitter.getFullMessage());
+        assertNotNull(emitter.getTitleMessage());
+        assertNotNull(emitter.getErrorStatus());
+    }
+
+    /**
+     * Tests adding an error and verifying that it is correctly registered and demontrated through the emitter.
+     */
+    @Test
+    void addError() {
+        emitter.addError("Test error", "Some message", 1);
+        assertTrue(emitter.foundError(), "Emitter should report found error");
+        assertTrue(emitter.getFullMessage().contains("Some message"));
+    }
+}