diff --git a/core/pom.xml b/core/pom.xml
index a3c2a1a1e9..e34cb44596 100644
--- a/core/pom.xml
+++ b/core/pom.xml
@@ -86,8 +86,23 @@
             <scope>test</scope>
         </dependency>
         <dependency>
-            <groupId>org.hsqldb</groupId>
-            <artifactId>hsqldb</artifactId>
+            <groupId>org.testcontainers</groupId>
+            <artifactId>junit-jupiter</artifactId>
+            <scope>test</scope>
+        </dependency>
+        <dependency>
+            <groupId>org.testcontainers</groupId>
+            <artifactId>mariadb</artifactId>
+            <scope>test</scope>
+        </dependency>
+        <dependency>
+            <groupId>org.mariadb.jdbc</groupId>
+            <artifactId>mariadb-java-client</artifactId>
+            <scope>test</scope>
+        </dependency>
+        <dependency>
+            <groupId>org.flywaydb</groupId>
+            <artifactId>flyway-mysql</artifactId>
             <scope>test</scope>
         </dependency>
 
diff --git a/core/src/main/resources/META-INF/persistence.xml b/core/src/main/resources/META-INF/persistence.xml
index fc5f0a5977..902cc7aeae 100755
--- a/core/src/main/resources/META-INF/persistence.xml
+++ b/core/src/main/resources/META-INF/persistence.xml
@@ -4,9 +4,6 @@
              xsi:schemaLocation="https://jakarta.ee/xml/ns/persistence https://jakarta.ee/xml/ns/persistence/persistence_3_0.xsd"
              version="3.0">
 
-    <!-- NOTE THAT THERE ARE TWO PERSISTENCE UNITS, one default and one test
-            used for either running or unit-tests -->
-
     <!-- A JPA Persistence Unit -->
     <persistence-unit name="defaultPersistenceUnit"
                       transaction-type="RESOURCE_LOCAL">
@@ -17,13 +14,4 @@
         </properties>
     </persistence-unit>
 
-    <!-- A JPA Persistence Unit used for tests -->
-    <persistence-unit name="testPersistenceUnit"
-                      transaction-type="RESOURCE_LOCAL">
-        <properties>
-            <property name="jakarta.persistence.jdbc.driver" value="org.hsqldb.jdbc.JDBCDriver"/>
-            <property name="jakarta.persistence.jdbc.url" value="jdbc:hsqldb:mem:test"/>
-            <property name="hibernate.hbm2ddl.auto" value="create"/>
-        </properties>
-    </persistence-unit>
 </persistence>
diff --git a/core/src/test/java/se/su/dsv/scipro/finalseminar/FinalSeminarSchedulingTest.java b/core/src/test/java/se/su/dsv/scipro/finalseminar/FinalSeminarSchedulingTest.java
index 23ebd8113c..cca047aed5 100644
--- a/core/src/test/java/se/su/dsv/scipro/finalseminar/FinalSeminarSchedulingTest.java
+++ b/core/src/test/java/se/su/dsv/scipro/finalseminar/FinalSeminarSchedulingTest.java
@@ -197,6 +197,7 @@ public class FinalSeminarSchedulingTest extends IntegrationTest {
         NonWorkDayPeriod nonWorkDayPeriod = new NonWorkDayPeriod();
         nonWorkDayPeriod.setStartDate(date);
         nonWorkDayPeriod.setEndDate(date);
+        nonWorkDayPeriod.setComment("test non work day");
         save(nonWorkDayPeriod);
     }
 
diff --git a/core/src/test/java/se/su/dsv/scipro/peer/CommentThreadServiceImplTest.java b/core/src/test/java/se/su/dsv/scipro/peer/CommentThreadServiceImplTest.java
index cd037f3ee5..625162f167 100644
--- a/core/src/test/java/se/su/dsv/scipro/peer/CommentThreadServiceImplTest.java
+++ b/core/src/test/java/se/su/dsv/scipro/peer/CommentThreadServiceImplTest.java
@@ -12,6 +12,7 @@ import se.su.dsv.scipro.file.FileDescription;
 import se.su.dsv.scipro.file.FileReference;
 import se.su.dsv.scipro.project.Project;
 import se.su.dsv.scipro.system.DegreeType;
+import se.su.dsv.scipro.system.Language;
 import se.su.dsv.scipro.system.ProjectType;
 import se.su.dsv.scipro.system.User;
 import se.su.dsv.scipro.test.Dates;
@@ -66,6 +67,7 @@ public class CommentThreadServiceImplTest extends IntegrationTest {
         PeerRequest peerRequest = new PeerRequest();
         peerRequest.setProject(project);
         peerRequest.setRequester(createUser());
+        peerRequest.setLanguage(Language.ENGLISH);
         final FileDescription fileDescription = save(new FileDescription());
         final FileReference fileReference = new FileReference();
         fileReference.setFileDescription(fileDescription);
diff --git a/core/src/test/java/se/su/dsv/scipro/peer/PeerRequestServiceImplTest.java b/core/src/test/java/se/su/dsv/scipro/peer/PeerRequestServiceImplTest.java
index 215e6c5f45..fc98ba6f7b 100644
--- a/core/src/test/java/se/su/dsv/scipro/peer/PeerRequestServiceImplTest.java
+++ b/core/src/test/java/se/su/dsv/scipro/peer/PeerRequestServiceImplTest.java
@@ -13,6 +13,7 @@ import se.su.dsv.scipro.file.FileDescription;
 import se.su.dsv.scipro.file.FileReference;
 import se.su.dsv.scipro.project.Project;
 import se.su.dsv.scipro.system.DegreeType;
+import se.su.dsv.scipro.system.Language;
 import se.su.dsv.scipro.system.PageRequest;
 import se.su.dsv.scipro.system.ProjectType;
 import se.su.dsv.scipro.system.User;
@@ -158,6 +159,7 @@ public class PeerRequestServiceImplTest extends IntegrationTest {
         peerRequest.setProject(project);
         peerRequest.setRequester(requester);
         peerRequest.setStatus(status);
+        peerRequest.setLanguage(Language.ENGLISH);
         final FileDescription fileDescription = save(new FileDescription());
         final FileReference fileReference = new FileReference();
         fileReference.setFileDescription(fileDescription);
diff --git a/core/src/test/java/se/su/dsv/scipro/peer/PeerReviewServiceImplIntegrationTest.java b/core/src/test/java/se/su/dsv/scipro/peer/PeerReviewServiceImplIntegrationTest.java
index 15a004fd89..a954f455be 100644
--- a/core/src/test/java/se/su/dsv/scipro/peer/PeerReviewServiceImplIntegrationTest.java
+++ b/core/src/test/java/se/su/dsv/scipro/peer/PeerReviewServiceImplIntegrationTest.java
@@ -14,6 +14,7 @@ import se.su.dsv.scipro.file.FileDescription;
 import se.su.dsv.scipro.file.FileReference;
 import se.su.dsv.scipro.project.Project;
 import se.su.dsv.scipro.system.DegreeType;
+import se.su.dsv.scipro.system.Language;
 import se.su.dsv.scipro.system.PageRequest;
 import se.su.dsv.scipro.system.ProjectType;
 import se.su.dsv.scipro.system.User;
@@ -102,6 +103,7 @@ public class PeerReviewServiceImplIntegrationTest extends IntegrationTest {
         PeerRequest peerRequest = new PeerRequest();
         peerRequest.setProject(createProject());
         peerRequest.setRequester(createUser());
+        peerRequest.setLanguage(Language.ENGLISH);
         final FileDescription fileDescription = save(new FileDescription());
         final FileReference fileReference = new FileReference();
         fileReference.setFileDescription(fileDescription);
diff --git a/core/src/test/java/se/su/dsv/scipro/peer/PeerReviewServiceImplTest.java b/core/src/test/java/se/su/dsv/scipro/peer/PeerReviewServiceImplTest.java
index 9c6a5dd3da..6495faaf7a 100644
--- a/core/src/test/java/se/su/dsv/scipro/peer/PeerReviewServiceImplTest.java
+++ b/core/src/test/java/se/su/dsv/scipro/peer/PeerReviewServiceImplTest.java
@@ -14,6 +14,7 @@ import se.su.dsv.scipro.file.FileDescription;
 import se.su.dsv.scipro.file.FileReference;
 import se.su.dsv.scipro.project.Project;
 import se.su.dsv.scipro.system.DegreeType;
+import se.su.dsv.scipro.system.Language;
 import se.su.dsv.scipro.system.PageRequest;
 import se.su.dsv.scipro.system.ProjectType;
 import se.su.dsv.scipro.system.User;
@@ -95,6 +96,7 @@ public class PeerReviewServiceImplTest extends IntegrationTest {
         peerRequest.setRequester(
             save(User.builder().firstName("Bob").lastName("Sponge").emailAddress("bob@example.com").build())
         );
+        peerRequest.setLanguage(Language.ENGLISH);
         final FileDescription fileDescription = save(new FileDescription());
         final FileReference fileReference = new FileReference();
         fileReference.setFileDescription(fileDescription);
diff --git a/core/src/test/java/se/su/dsv/scipro/peer/TestPeerReview.java b/core/src/test/java/se/su/dsv/scipro/peer/TestPeerReview.java
index 34e5e5c7e2..fe5e2be992 100755
--- a/core/src/test/java/se/su/dsv/scipro/peer/TestPeerReview.java
+++ b/core/src/test/java/se/su/dsv/scipro/peer/TestPeerReview.java
@@ -19,6 +19,7 @@ import se.su.dsv.scipro.file.FileDescription;
 import se.su.dsv.scipro.file.FileReference;
 import se.su.dsv.scipro.project.Project;
 import se.su.dsv.scipro.project.ProjectStatus;
+import se.su.dsv.scipro.system.Language;
 import se.su.dsv.scipro.system.PageRequest;
 import se.su.dsv.scipro.system.ProjectType;
 import se.su.dsv.scipro.system.User;
@@ -196,6 +197,7 @@ public class TestPeerReview extends IntegrationTest {
         request.setComment(comment);
         request.setRequester(requester);
         request.setProject(project);
+        request.setLanguage(Language.ENGLISH);
         final FileDescription fileDescription = save(new FileDescription());
         final FileReference fileReference = new FileReference();
         fileReference.setFileDescription(fileDescription);
diff --git a/core/src/test/java/se/su/dsv/scipro/plagiarism/urkund/UrkundSubmissionRepositoryTest.java b/core/src/test/java/se/su/dsv/scipro/plagiarism/urkund/UrkundSubmissionRepositoryTest.java
index c09f3ea67e..a3b40ed7ae 100644
--- a/core/src/test/java/se/su/dsv/scipro/plagiarism/urkund/UrkundSubmissionRepositoryTest.java
+++ b/core/src/test/java/se/su/dsv/scipro/plagiarism/urkund/UrkundSubmissionRepositoryTest.java
@@ -13,6 +13,7 @@ import org.hamcrest.TypeSafeMatcher;
 import org.junit.jupiter.api.Test;
 import se.su.dsv.scipro.file.FileDescription;
 import se.su.dsv.scipro.file.FileReference;
+import se.su.dsv.scipro.system.User;
 import se.su.dsv.scipro.test.SpringTest;
 
 public class UrkundSubmissionRepositoryTest extends SpringTest {
@@ -23,11 +24,14 @@ public class UrkundSubmissionRepositoryTest extends SpringTest {
     @Test
     public void save() {
         final Instant submitted = Instant.now();
+        User bob = User.builder().firstName("Bob").lastName("Sponge").emailAddress("bob@example.com").build();
+        save(bob);
         final UrkundSubmission submission = new UrkundSubmission();
         submission.setState(UrkundSubmission.State.SUBMITTED);
         submission.setMessage("Hi");
         submission.setSubmitted(submitted);
         submission.setNextPoll(submitted);
+        submission.setReceiver(bob);
         final FileDescription file = save(new FileDescription());
         final FileReference fileReference = new FileReference();
         fileReference.setFileDescription(file);
diff --git a/core/src/test/java/se/su/dsv/scipro/test/SpringTest.java b/core/src/test/java/se/su/dsv/scipro/test/SpringTest.java
index 2b68b55008..04d0f70da7 100644
--- a/core/src/test/java/se/su/dsv/scipro/test/SpringTest.java
+++ b/core/src/test/java/se/su/dsv/scipro/test/SpringTest.java
@@ -4,28 +4,47 @@ import jakarta.persistence.EntityManager;
 import jakarta.persistence.EntityManagerFactory;
 import jakarta.persistence.EntityTransaction;
 import jakarta.persistence.Persistence;
+import java.sql.SQLException;
 import java.time.Clock;
+import java.util.Map;
 import java.util.Optional;
+import org.flywaydb.core.Flyway;
+import org.hibernate.cfg.Environment;
 import org.junit.jupiter.api.AfterEach;
 import org.junit.jupiter.api.BeforeEach;
+import org.mariadb.jdbc.MariaDbDataSource;
 import org.springframework.context.annotation.AnnotationConfigApplicationContext;
 import org.springframework.context.annotation.Bean;
 import org.springframework.context.annotation.Configuration;
 import org.springframework.context.annotation.Import;
+import org.testcontainers.containers.MariaDBContainer;
+import org.testcontainers.junit.jupiter.Container;
+import org.testcontainers.junit.jupiter.Testcontainers;
 import se.su.dsv.scipro.CoreConfig;
 import se.su.dsv.scipro.RepositoryConfiguration;
 import se.su.dsv.scipro.profiles.CurrentProfile;
 import se.su.dsv.scipro.sukat.Sukat;
 import se.su.dsv.scipro.system.CurrentUser;
 
+@Testcontainers
 public abstract class SpringTest {
 
     private EntityManager entityManager;
     private EntityManagerFactory entityManagerFactory;
 
+    @Container
+    static MariaDBContainer<?> mariaDBContainer = new MariaDBContainer<>("mariadb:10.11");
+
     @BeforeEach
-    public final void prepareSpring() {
-        entityManagerFactory = Persistence.createEntityManagerFactory("testPersistenceUnit");
+    public final void prepareSpring() throws SQLException {
+        MariaDbDataSource dataSource = new MariaDbDataSource(mariaDBContainer.getJdbcUrl());
+        dataSource.setUser(mariaDBContainer.getUsername());
+        dataSource.setPassword(mariaDBContainer.getPassword());
+
+        Flyway.configure().dataSource(dataSource).load().migrate();
+
+        Map<String, Object> jpaProperties = Map.of(Environment.JAKARTA_JTA_DATASOURCE, dataSource);
+        entityManagerFactory = Persistence.createEntityManagerFactory("defaultPersistenceUnit", jpaProperties);
         this.entityManager = entityManagerFactory.createEntityManager();
         EntityTransaction transaction = entityManager.getTransaction();
         transaction.begin();
diff --git a/pom.xml b/pom.xml
index 8448e670cf..a4b4f57961 100755
--- a/pom.xml
+++ b/pom.xml
@@ -34,7 +34,6 @@
         <querydsl.version>5.0.0</querydsl.version>
         <jakarta.servlet.version>5.0.0</jakarta.servlet.version>
         <junit.version>5.9.3</junit.version>
-        <hsqldb.version>2.7.1</hsqldb.version>
         <mockito.version>5.3.1</mockito.version>
         <flyway.version>9.19.1</flyway.version>
         <jersey.version>3.1.6</jersey.version>
@@ -133,14 +132,6 @@
                 <scope>import</scope>
             </dependency>
 
-            <!-- Database stuff -->
-            <dependency>
-                <groupId>org.hsqldb</groupId>
-                <artifactId>hsqldb</artifactId>
-                <version>${hsqldb.version}</version>
-                <scope>test</scope>
-            </dependency>
-
             <dependency>
                 <groupId>org.mariadb.jdbc</groupId>
                 <artifactId>mariadb-java-client</artifactId>