diff --git a/build.gradle b/build.gradle
index e664287e..7f1f6b7f 100644
--- a/build.gradle
+++ b/build.gradle
@@ -31,6 +31,7 @@ plugins {
 }
 
 apply plugin: 'java'
+apply plugin: 'jacoco'
 apply plugin: 'org.owasp.dependencycheck'
 sourceCompatibility=1.8
 targetCompatibility=1.8
@@ -111,6 +112,75 @@ test {
     reports.html.enabled = false
 }
 
+// --- JaCoCo Code Coverage ---
+
+jacoco {
+    toolVersion = "0.8.3"
+}
+
+test.finalizedBy jacocoTestReport
+check.dependsOn jacocoTestCoverageVerification
+
+// Only for purely JHipster/MapStruct generated classes.
+// Please do NOT add any self coded classes!
+// Keep in mind, git will blame you ;-)
+def jhipsterGeneratedClassesWithDecentCoverage = [
+    'org.hostsharing.hsadminng.repository.CustomAuditEventRepository',
+    'org.hostsharing.hsadminng.service.ContactQueryService',
+    'org.hostsharing.hsadminng.service.UserService',
+    'org.hostsharing.hsadminng.service.CustomerContactQueryService'
+]
+
+// Only for purely JHipster/MapStruct generated classes.
+// Please do NOT add any self coded classes!
+// Keep in mind, git will blame you ;-)
+def jhipsterGeneratedClassesWithLowCoverage = [
+    'org.hostsharing.hsadminng.service.MailService',
+    'org.hostsharing.hsadminng.security.SecurityUtils',
+    'org.hostsharing.hsadminng.config.DefaultProfileUtil',
+    'org.hostsharing.hsadminng.config.WebConfigurer',
+    'org.hostsharing.hsadminng.web.rest.AccountResource',
+    'org.hostsharing.hsadminng.web.rest.errors.ExceptionTranslator',
+    'org.hostsharing.hsadminng.web.rest.errors.CustomParameterizedException',
+    'org.hostsharing.hsadminng.config.audit.AuditEventConverter',
+    'org.hostsharing.hsadminng.security.jwt.TokenProvider',
+    'org.hostsharing.hsadminng.aop.logging.LoggingAspect',
+    'org.hostsharing.hsadminng.HsadminNgApp',
+    '*.*QueryService',
+    '*.*Configuration',
+    '*MapperImpl',
+    '*Criteria',
+    '*_'
+]
+
+jacocoTestCoverageVerification {
+    violationRules {
+        rule {
+            element = 'CLASS'
+            limit {
+                counter = 'BRANCH'
+                value = 'COVEREDRATIO'
+                // Increasing the threshold is fine, decreasing is not.
+                // Keep in mind, git will blame you ;-)
+                minimum = 0.95
+            }
+            excludes = jhipsterGeneratedClassesWithDecentCoverage + jhipsterGeneratedClassesWithLowCoverage
+        }
+
+        rule {
+            element = 'CLASS'
+            limit {
+                counter = 'BRANCH'
+                value = 'COVEREDRATIO'
+                minimum = 0.85
+            }
+            includes = jhipsterGeneratedClassesWithDecentCoverage
+        }
+    }
+}
+
+// --- Cucumber BDD Tests ---
+
 task cucumberTest(type: Test) {
     description = "Execute cucumber BDD tests."
     group = "verification"
@@ -133,6 +203,8 @@ task cucumberTestReport(type: TestReport) {
     reportOn cucumberTest
 }
 
+// ------------------------------
+
 apply from: 'gradle/docker.gradle'
 apply from: 'gradle/sonar.gradle'
 apply from: 'gradle/swagger.gradle'
diff --git a/src/main/java/org/hostsharing/hsadminng/web/rest/ShareResource.java b/src/main/java/org/hostsharing/hsadminng/web/rest/ShareResource.java
index d7c2d2f2..64bc8430 100644
--- a/src/main/java/org/hostsharing/hsadminng/web/rest/ShareResource.java
+++ b/src/main/java/org/hostsharing/hsadminng/web/rest/ShareResource.java
@@ -1,25 +1,24 @@
 package org.hostsharing.hsadminng.web.rest;
+
+import io.github.jhipster.web.util.ResponseUtil;
+import org.hostsharing.hsadminng.service.ShareQueryService;
 import org.hostsharing.hsadminng.service.ShareService;
+import org.hostsharing.hsadminng.service.dto.ShareCriteria;
+import org.hostsharing.hsadminng.service.dto.ShareDTO;
 import org.hostsharing.hsadminng.web.rest.errors.BadRequestAlertException;
 import org.hostsharing.hsadminng.web.rest.util.HeaderUtil;
 import org.hostsharing.hsadminng.web.rest.util.PaginationUtil;
-import org.hostsharing.hsadminng.service.dto.ShareDTO;
-import org.hostsharing.hsadminng.service.dto.ShareCriteria;
-import org.hostsharing.hsadminng.service.ShareQueryService;
-import io.github.jhipster.web.util.ResponseUtil;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 import org.springframework.data.domain.Page;
 import org.springframework.data.domain.Pageable;
 import org.springframework.http.HttpHeaders;
-import org.springframework.http.HttpStatus;
 import org.springframework.http.ResponseEntity;
 import org.springframework.web.bind.annotation.*;
 
 import javax.validation.Valid;
 import java.net.URI;
 import java.net.URISyntaxException;
-
 import java.util.List;
 import java.util.Optional;
 
@@ -74,13 +73,8 @@ public class ShareResource {
     @PutMapping("/shares")
     public ResponseEntity<ShareDTO> updateShare(@Valid @RequestBody ShareDTO shareDTO) throws URISyntaxException {
         log.debug("REST request to update Share : {}", shareDTO);
-        if (shareDTO.getId() == null) {
-            throw new BadRequestAlertException("Invalid id", ENTITY_NAME, "idnull");
-        }
-        ShareDTO result = shareService.save(shareDTO);
-        return ResponseEntity.ok()
-            .headers(HeaderUtil.createEntityUpdateAlert(ENTITY_NAME, shareDTO.getId().toString()))
-            .body(result);
+        // TODO mhoennig: Rather completely remove the endpoint?
+        throw new BadRequestAlertException("Shares are immutable", ENTITY_NAME, "shareTransactionImmutable");
     }
 
     /**
@@ -132,7 +126,7 @@ public class ShareResource {
     @DeleteMapping("/shares/{id}")
     public ResponseEntity<Void> deleteShare(@PathVariable Long id) {
         log.debug("REST request to delete Share : {}", id);
-        shareService.delete(id);
-        return ResponseEntity.ok().headers(HeaderUtil.createEntityDeletionAlert(ENTITY_NAME, id.toString())).build();
+        // TODO mhoennig: Rather completely remove the endpoint?
+        throw new BadRequestAlertException("Shares are immutable", ENTITY_NAME, "shareTransactionImmutable");
     }
 }