diff --git a/client/src/components/competences/PerformanceCriteriaRow.vue b/client/src/components/competences/PerformanceCriteriaRow.vue
index a0ecd306..7bdc099a 100644
--- a/client/src/components/competences/PerformanceCriteriaRow.vue
+++ b/client/src/components/competences/PerformanceCriteriaRow.vue
@@ -19,10 +19,10 @@ const props = withDefaults(defineProps<Props>(), {
     <div class="flex flex-row items-center">
       <div v-if="showState" class="mr-4 h-8 w-8">
         <it-icon-smiley-happy
-          v-if="criteria.completion_status === 'success'"
+          v-if="criteria.completion_status === 'SUCCESS'"
         ></it-icon-smiley-happy>
         <it-icon-smiley-thinking
-          v-else-if="criteria.completion_status === 'fail'"
+          v-else-if="criteria.completion_status === 'FAIL'"
         ></it-icon-smiley-thinking>
         <it-icon-smiley-neutral v-else></it-icon-smiley-neutral>
       </div>
diff --git a/client/src/components/ui/ItProgress.vue b/client/src/components/ui/ItProgress.vue
index 37403218..fba9ec6b 100644
--- a/client/src/components/ui/ItProgress.vue
+++ b/client/src/components/ui/ItProgress.vue
@@ -1,7 +1,7 @@
 <script setup lang="ts">
 import { computed } from "vue";
 
-export type StatusCountKey = "fail" | "success" | "unknown";
+export type StatusCountKey = "FAIL" | "SUCCESS" | "UNKNOWN";
 export type StatusCount = Record<StatusCountKey, number>;
 
 const props = defineProps<{
@@ -10,9 +10,9 @@ const props = defineProps<{
 
 const total = computed(() => {
   return (
-    (props.statusCount?.fail || 0) +
-    (props.statusCount?.success || 0) +
-    (props.statusCount?.unknown || 0)
+    (props.statusCount?.FAIL || 0) +
+    (props.statusCount?.SUCCESS || 0) +
+    (props.statusCount?.UNKNOWN || 0)
   );
 });
 
@@ -21,7 +21,7 @@ const done = computed(() => {
     return 0;
   }
 
-  return ((props.statusCount?.success || 0) / total.value) * 100;
+  return ((props.statusCount?.SUCCESS || 0) / total.value) * 100;
 });
 
 const notDone = computed(() => {
@@ -29,7 +29,7 @@ const notDone = computed(() => {
     return 0;
   }
 
-  return ((props.statusCount?.fail || 0) / total.value) * 100 + done.value;
+  return ((props.statusCount?.FAIL || 0) / total.value) * 100 + done.value;
 });
 </script>
 
diff --git a/client/src/constants.ts b/client/src/constants.ts
index 4c7d1916..0b981057 100644
--- a/client/src/constants.ts
+++ b/client/src/constants.ts
@@ -1,5 +1,5 @@
 import type { CourseCompletionStatus } from "@/types";
 
-export const COMPLETION_SUCCESS: CourseCompletionStatus = "success";
-export const COMPLETION_FAILURE: CourseCompletionStatus = "fail";
-export const COMPLETION_UNKNOWN: CourseCompletionStatus = "unknown";
+export const COMPLETION_SUCCESS: CourseCompletionStatus = "SUCCESS";
+export const COMPLETION_FAILURE: CourseCompletionStatus = "FAIL";
+export const COMPLETION_UNKNOWN: CourseCompletionStatus = "UNKNOWN";
diff --git a/client/src/pages/cockpit/assignmentsPage/AssignmentDetails.vue b/client/src/pages/cockpit/assignmentsPage/AssignmentDetails.vue
index 515ad009..b36b0fdb 100644
--- a/client/src/pages/cockpit/assignmentsPage/AssignmentDetails.vue
+++ b/client/src/pages/cockpit/assignmentsPage/AssignmentDetails.vue
@@ -129,7 +129,7 @@ const assignmentDetail = computed(() =>
           </template>
           <template #link>
             <router-link
-              v-if="submissionStatusForUser(csu.user_id)?.progressStatus === 'success'"
+              v-if="submissionStatusForUser(csu.user_id)?.progressStatus === 'SUCCESS'"
               :to="`/course/${props.courseSession.course.slug}/cockpit/assignment/${assignment.assignmentId}/${csu.user_id}`"
               class="w-full text-right underline"
               data-cy="show-results"
diff --git a/client/src/pages/cockpit/assignmentsPage/AssignmentSubmissionProgress.vue b/client/src/pages/cockpit/assignmentsPage/AssignmentSubmissionProgress.vue
index 3a3aa87a..cb277c71 100644
--- a/client/src/pages/cockpit/assignmentsPage/AssignmentSubmissionProgress.vue
+++ b/client/src/pages/cockpit/assignmentsPage/AssignmentSubmissionProgress.vue
@@ -45,10 +45,10 @@ onMounted(async () => {
     </div>
     <div><ItProgress :status-count="state.progressStatusCount" /></div>
     <div class="text-gray-900" :class="{ 'text-gray-900': showTitle }">
-      {{ state.progressStatusCount.success || 0 }} von
+      {{ state.progressStatusCount.SUCCESS || 0 }} von
       {{
-        (state.progressStatusCount.success || 0) +
-        (state.progressStatusCount.unknown || 0)
+        (state.progressStatusCount.SUCCESS || 0) +
+        (state.progressStatusCount.UNKNOWN || 0)
       }}
       Lernenden haben ihre Ergebnisse eingereicht.
     </div>
diff --git a/client/src/pages/cockpit/cockpitPage/CockpitPage.vue b/client/src/pages/cockpit/cockpitPage/CockpitPage.vue
index cd45cbf1..d1630f85 100644
--- a/client/src/pages/cockpit/cockpitPage/CockpitPage.vue
+++ b/client/src/pages/cockpit/cockpitPage/CockpitPage.vue
@@ -174,7 +174,7 @@ function setActiveClasses(translationKey: string) {
                             class="mr-2 inline-block h-8 w-8"
                           ></it-icon-smiley-thinking>
                           <p class="text-bold inline-block">
-                            {{ userCountStatusForCircle(csu.user_id, circle).fail }}
+                            {{ userCountStatusForCircle(csu.user_id, circle).FAIL }}
                           </p>
                         </div>
                         <li class="mr-6 flex flex-row items-center">
@@ -182,7 +182,7 @@ function setActiveClasses(translationKey: string) {
                             class="mr-2 inline-block h-8 w-8"
                           ></it-icon-smiley-happy>
                           <p class="text-bold inline-block">
-                            {{ userCountStatusForCircle(csu.user_id, circle).success }}
+                            {{ userCountStatusForCircle(csu.user_id, circle).SUCCESS }}
                           </p>
                         </li>
                         <li class="flex flex-row items-center">
@@ -190,7 +190,7 @@ function setActiveClasses(translationKey: string) {
                             class="mr-2 inline-block h-8 w-8"
                           ></it-icon-smiley-neutral>
                           <p class="text-bold inline-block">
-                            {{ userCountStatusForCircle(csu.user_id, circle).unknown }}
+                            {{ userCountStatusForCircle(csu.user_id, circle).UNKNOWN }}
                           </p>
                         </li>
                       </div>
diff --git a/client/src/pages/competence/CompetenceIndexPage.vue b/client/src/pages/competence/CompetenceIndexPage.vue
index 235f1372..3ac8e99c 100644
--- a/client/src/pages/competence/CompetenceIndexPage.vue
+++ b/client/src/pages/competence/CompetenceIndexPage.vue
@@ -22,7 +22,7 @@ const failedCriteria = computed(() => {
   return competenceStore
     .flatPerformanceCriteria()
     .filter((criteria) => {
-      return criteria.completion_status === "fail";
+      return criteria.completion_status === "FAIL";
     })
     .slice(0, 3);
 });
@@ -111,7 +111,7 @@ const countStatus = computed(() => {
           <h5 class="mb-4 text-gray-700">«{{ $t("selfEvaluation.no") }}»</h5>
           <div class="flex flex-row items-center">
             <it-icon-smiley-thinking class="h-16 w-16"></it-icon-smiley-thinking>
-            <p class="ml-4 inline-block text-7xl font-bold">{{ countStatus.fail }}</p>
+            <p class="ml-4 inline-block text-7xl font-bold">{{ countStatus.FAIL }}</p>
           </div>
         </li>
         <li
@@ -121,7 +121,7 @@ const countStatus = computed(() => {
           <div class="flex flex-row items-center">
             <it-icon-smiley-happy class="h-16 w-16"></it-icon-smiley-happy>
             <p class="ml-4 inline-block text-7xl font-bold">
-              {{ countStatus.success }}
+              {{ countStatus.SUCCESS }}
             </p>
           </div>
         </li>
@@ -130,7 +130,7 @@ const countStatus = computed(() => {
           <div class="flex flex-row items-center">
             <it-icon-smiley-neutral class="h-16 w-16"></it-icon-smiley-neutral>
             <p class="ml-4 inline-block text-7xl font-bold">
-              {{ countStatus.unknown }}
+              {{ countStatus.UNKNOWN }}
             </p>
           </div>
         </li>
diff --git a/client/src/pages/competence/PerformanceCriteriaPage.vue b/client/src/pages/competence/PerformanceCriteriaPage.vue
index d4bb10ed..dfd96b54 100644
--- a/client/src/pages/competence/PerformanceCriteriaPage.vue
+++ b/client/src/pages/competence/PerformanceCriteriaPage.vue
@@ -32,17 +32,17 @@ const { t } = useTranslation();
 
 const mobileMenuItems: MenuItem[] = [
   {
-    id: "fail",
+    id: "FAIL",
     name: `«${t("selfEvaluation.no")}»`,
     iconName: "it-icon-smiley-thinking",
   },
   {
-    id: "success",
+    id: "SUCCESS",
     name: `«${t("selfEvaluation.yes")}»`,
     iconName: "it-icon-smiley-happy",
   },
   {
-    id: "unknown",
+    id: "UNKNOWN",
     name: t("competences.notAssessed"),
     iconName: "it-icon-smiley-neutral",
   },
@@ -91,7 +91,7 @@ function updateActiveState(status: CourseCompletionStatus) {
           :key="item.id"
           :class="{
             'bg-gray-200': activeMenuItem.id === item.id,
-            'mr-6': item.id !== 'unknown',
+            'mr-6': item.id !== 'UNKNOWN',
           }"
           class="mr-6 inline-block px-2 py-4"
           @click="updateActiveState(item.id)"
diff --git a/client/src/pages/competence/SinglePerformanceCriteriaPage.vue b/client/src/pages/competence/SinglePerformanceCriteriaPage.vue
index c9068206..4e3a9f5d 100644
--- a/client/src/pages/competence/SinglePerformanceCriteriaPage.vue
+++ b/client/src/pages/competence/SinglePerformanceCriteriaPage.vue
@@ -39,11 +39,11 @@ const singleCriteria = computed(() => {
             <button
               class="inline-flex flex-1 items-center border p-4 text-left"
               :class="{
-                'border-green-500': singleCriteria.completion_status === 'success',
-                'border-2': singleCriteria.completion_status === 'success',
+                'border-green-500': singleCriteria.completion_status === 'SUCCESS',
+                'border-2': singleCriteria.completion_status === 'SUCCESS',
               }"
               data-cy="success"
-              @click="circleStore.markCompletion(singleCriteria, 'success')"
+              @click="circleStore.markCompletion(singleCriteria, 'SUCCESS')"
             >
               <it-icon-smiley-happy class="mr-4 h-16 w-16"></it-icon-smiley-happy>
               <span class="text-large font-bold">{{ $t("selfEvaluation.yes") }}</span>
@@ -51,11 +51,11 @@ const singleCriteria = computed(() => {
             <button
               class="inline-flex flex-1 items-center border p-4 text-left"
               :class="{
-                'border-orange-500': singleCriteria.completion_status === 'fail',
-                'border-2': singleCriteria.completion_status === 'fail',
+                'border-orange-500': singleCriteria.completion_status === 'FAIL',
+                'border-2': singleCriteria.completion_status === 'FAIL',
               }"
               data-cy="fail"
-              @click="circleStore.markCompletion(singleCriteria, 'fail')"
+              @click="circleStore.markCompletion(singleCriteria, 'FAIL')"
             >
               <it-icon-smiley-thinking class="mr-4 h-16 w-16"></it-icon-smiley-thinking>
               <span class="text-xl font-bold">{{ $t("selfEvaluation.no") }}</span>
diff --git a/client/src/pages/learningPath/circlePage/LearningSequence.vue b/client/src/pages/learningPath/circlePage/LearningSequence.vue
index 6fd0d5ba..69798e5a 100644
--- a/client/src/pages/learningPath/circlePage/LearningSequence.vue
+++ b/client/src/pages/learningPath/circlePage/LearningSequence.vue
@@ -24,9 +24,9 @@ const props = withDefaults(defineProps<Props>(), {
 const circleStore = useCircleStore();
 
 function toggleCompleted(learningContent: LearningContentInterface) {
-  let completionStatus: CourseCompletionStatus = "success";
-  if (learningContent.completion_status === "success") {
-    completionStatus = "fail";
+  let completionStatus: CourseCompletionStatus = "SUCCESS";
+  if (learningContent.completion_status === "SUCCESS") {
+    completionStatus = "FAIL";
   }
   circleStore.markCompletion(learningContent, completionStatus);
 }
@@ -56,7 +56,7 @@ const continueTranslationKeyTuple = computed(() => {
     const lastFinished = findLast(
       circleStore.circle.flatLearningContents,
       (learningContent) => {
-        return learningContent.completion_status === "success";
+        return learningContent.completion_status === "SUCCESS";
       }
     );
 
@@ -127,7 +127,7 @@ const learningSequenceBorderClass = computed(() => {
           >
             <div v-if="props.readonly">
               <it-icon-check
-                v-if="learningContent.completion_status === 'success'"
+                v-if="learningContent.completion_status === 'SUCCESS'"
                 class="block h-8 w-8"
               ></it-icon-check>
               <div v-else class="h-8 w-8"></div>
@@ -136,7 +136,7 @@ const learningSequenceBorderClass = computed(() => {
               v-else
               :checkbox-item="{
                 value: learningContent.completion_status,
-                checked: learningContent.completion_status === 'success',
+                checked: learningContent.completion_status === 'SUCCESS',
               }"
               :data-cy="`${learningContent.slug}-checkbox`"
               @toggle="toggleCompleted(learningContent)"
@@ -194,14 +194,14 @@ const learningSequenceBorderClass = computed(() => {
           @click="!props.readonly && circleStore.openSelfEvaluation(learningUnit)"
         >
           <div
-            v-if="circleStore.calcSelfEvaluationStatus(learningUnit) === 'success'"
+            v-if="circleStore.calcSelfEvaluationStatus(learningUnit) === 'SUCCESS'"
             class="self-evaluation-success flex items-center gap-4 pb-3 lg:pb-6"
           >
             <it-icon-smiley-happy class="h-8 w-8 flex-none" data-cy="success" />
             <div>{{ $t("selfEvaluation.selfEvaluationYes") }}</div>
           </div>
           <div
-            v-else-if="circleStore.calcSelfEvaluationStatus(learningUnit) === 'fail'"
+            v-else-if="circleStore.calcSelfEvaluationStatus(learningUnit) === 'FAIL'"
             class="self-evaluation-fail flex items-center gap-4 pb-3 lg:pb-6"
           >
             <it-icon-smiley-thinking class="h-8 w-8 flex-none" data-cy="fail" />
diff --git a/client/src/pages/learningPath/selfEvaluationPage/SelfEvaluation.vue b/client/src/pages/learningPath/selfEvaluationPage/SelfEvaluation.vue
index 100689db..d2c1c350 100644
--- a/client/src/pages/learningPath/selfEvaluationPage/SelfEvaluation.vue
+++ b/client/src/pages/learningPath/selfEvaluationPage/SelfEvaluation.vue
@@ -93,8 +93,8 @@ onUnmounted(() => {
               <button
                 class="inline-flex flex-1 items-center border p-4 text-left"
                 :class="{
-                  'border-green-500': currentQuestion.completion_status === 'success',
-                  'border-2': currentQuestion.completion_status === 'success',
+                  'border-green-500': currentQuestion.completion_status === 'SUCCESS',
+                  'border-2': currentQuestion.completion_status === 'SUCCESS',
                 }"
                 data-cy="success"
                 @click="circleStore.markCompletion(currentQuestion, COMPLETION_SUCCESS)"
@@ -112,7 +112,7 @@ onUnmounted(() => {
                   'border-2': currentQuestion.completion_status === COMPLETION_FAILURE,
                 }"
                 data-cy="fail"
-                @click="circleStore.markCompletion(currentQuestion, 'fail')"
+                @click="circleStore.markCompletion(currentQuestion, 'FAIL')"
               >
                 <it-icon-smiley-thinking
                   class="mr-4 h-16 w-16"
diff --git a/client/src/services/assignmentService.ts b/client/src/services/assignmentService.ts
index 3db79596..c8ffe276 100644
--- a/client/src/services/assignmentService.ts
+++ b/client/src/services/assignmentService.ts
@@ -70,13 +70,13 @@ export function calcUserAssignmentCompletionStatus(
     if (userAssignmentStatus) {
       userStatus = userAssignmentStatus.completion_status;
     }
-    let progressStatus: StatusCountKey = "unknown";
+    let progressStatus: StatusCountKey = "UNKNOWN";
     if (
       ["SUBMITTED", "EVALUATION_IN_PROGRESS", "EVALUATION_SUBMITTED"].includes(
         userStatus
       )
     ) {
-      progressStatus = "success";
+      progressStatus = "SUCCESS";
     }
 
     return {
diff --git a/client/src/services/circle.ts b/client/src/services/circle.ts
index 1455c12e..bd82b4ca 100644
--- a/client/src/services/circle.ts
+++ b/client/src/services/circle.ts
@@ -203,7 +203,7 @@ export class Circle implements WagtailCircle {
       return (
         this.flatChildren.filter((lc) => {
           return (
-            lc.completion_status === "success" &&
+            lc.completion_status === "SUCCESS" &&
             lc.parentLearningSequence?.translation_key === translationKey
           );
         }).length > 0
@@ -229,12 +229,12 @@ export class Circle implements WagtailCircle {
       );
 
       return (
-        learningContents.every((lc) => lc.completion_status === "success") &&
+        learningContents.every((lc) => lc.completion_status === "SUCCESS") &&
         (groupedPerformanceCriteria.length === 0 ||
           groupedPerformanceCriteria.every((group) =>
             group.every(
               (pc) =>
-                pc.completion_status === "success" || pc.completion_status === "fail"
+                pc.completion_status === "SUCCESS" || pc.completion_status === "FAIL"
             )
           ))
       );
@@ -252,12 +252,12 @@ export class Circle implements WagtailCircle {
   public parseCompletionData(completionData: CourseCompletion[]) {
     this.flatChildren.forEach((page) => {
       const pageIndex = completionData.findIndex((e) => {
-        return e.page_key === page.translation_key;
+        return e.page_id === page.id;
       });
       if (pageIndex >= 0) {
         page.completion_status = completionData[pageIndex].completion_status;
       } else {
-        page.completion_status = "unknown";
+        page.completion_status = "UNKNOWN";
       }
     });
 
diff --git a/client/src/services/learningPath.ts b/client/src/services/learningPath.ts
index 05104da7..6d0a9727 100644
--- a/client/src/services/learningPath.ts
+++ b/client/src/services/learningPath.ts
@@ -25,7 +25,7 @@ function getLastCompleted(courseSlug: string, completionData: CourseCompletion[]
   const courseSession = courseSessionsStore.courseSessionForCourse(courseSlug);
   return orderBy(completionData, ["updated_at"], "desc").find((c: CourseCompletion) => {
     return (
-      c.completion_status === "success" &&
+      c.completion_status === "SUCCESS" &&
       c.course_session === courseSession?.id &&
       c.page_type.startsWith("learnpath.LearningContent")
     );
@@ -129,13 +129,13 @@ export class LearningPath implements WagtailLearningPath {
       const lastCircle = this.circles.find((circle) => {
         return circle.flatLearningContents.find(
           (learningContent) =>
-            learningContent.translation_key === lastCompletedLearningContent.page_key
+            learningContent.id === lastCompletedLearningContent.page_id
         );
       });
       if (lastCircle) {
         const lastLearningContent = lastCircle.flatLearningContents.find(
           (learningContent) =>
-            learningContent.translation_key === lastCompletedLearningContent.page_key
+            learningContent.id === lastCompletedLearningContent.page_id
         );
         if (lastLearningContent && lastLearningContent.nextLearningContent) {
           this.nextLearningContent = lastLearningContent.nextLearningContent;
diff --git a/client/src/stores/circle.ts b/client/src/stores/circle.ts
index 7b89ae59..62f0f84e 100644
--- a/client/src/stores/circle.ts
+++ b/client/src/stores/circle.ts
@@ -105,7 +105,7 @@ export const useCircleStore = defineStore({
         | LearningUnitPerformanceCriteria
         | PerformanceCriteria
         | undefined,
-      completion_status: CourseCompletionStatus = "success"
+      completion_status: CourseCompletionStatus = "SUCCESS"
     ) {
       const completionStore = useCompletionStore();
 
@@ -146,22 +146,22 @@ export const useCircleStore = defineStore({
     },
     calcSelfEvaluationStatus(learningUnit: LearningUnit): CourseCompletionStatus {
       if (learningUnit.children.length > 0) {
-        if (learningUnit.children.every((q) => q.completion_status === "success")) {
-          return "success";
+        if (learningUnit.children.every((q) => q.completion_status === "SUCCESS")) {
+          return "SUCCESS";
         }
         if (
           learningUnit.children.every(
-            (q) => q.completion_status === "fail" || q.completion_status === "success"
+            (q) => q.completion_status === "FAIL" || q.completion_status === "SUCCESS"
           )
         ) {
-          return "fail";
+          return "FAIL";
         }
       }
-      return "unknown";
+      return "UNKNOWN";
     },
     continueFromLearningContent(currentLearningContent: LearningContentInterface) {
       if (currentLearningContent) {
-        this.markCompletion(currentLearningContent, "success");
+        this.markCompletion(currentLearningContent, "SUCCESS");
         this.closeLearningContent(currentLearningContent);
       } else {
         log.error("currentLearningContent is undefined");
diff --git a/client/src/stores/competence.ts b/client/src/stores/competence.ts
index 6a80960e..c6e54e4f 100644
--- a/client/src/stores/competence.ts
+++ b/client/src/stores/competence.ts
@@ -35,16 +35,16 @@ export const useCompetenceStore = defineStore({
       if (criteria) {
         const grouped = groupBy(criteria, "completion_status");
         return {
-          fail: grouped?.fail?.length || 0,
-          success: grouped?.success?.length || 0,
-          unknown: grouped?.unknown?.length || 0,
+          FAIL: grouped?.FAIL.length || 0,
+          SUCCESS: grouped?.SUCCESS.length || 0,
+          UNKNOWN: grouped?.UNKNOWN.length || 0,
         };
       }
 
       return {
-        success: 0,
-        fail: 0,
-        unknown: 0,
+        SUCCESS: 0,
+        FAIL: 0,
+        UNKNOWN: 0,
       };
     },
     criteriaByCompetence(competence: CompetencePage) {
@@ -177,14 +177,14 @@ export const useCompetenceStore = defineStore({
             competenceProfilePage.children.forEach((competence) => {
               competence.children.forEach((performanceCriteria) => {
                 const completion = completionData.find(
-                  (c) => c.page_key === performanceCriteria.translation_key
+                  (c) => c.page_id === performanceCriteria.id
                 );
                 if (completion) {
                   performanceCriteria.completion_status = completion.completion_status;
                   performanceCriteria.completion_status_updated_at =
                     completion.updated_at;
                 } else {
-                  performanceCriteria.completion_status = "unknown";
+                  performanceCriteria.completion_status = "UNKNOWN";
                   performanceCriteria.completion_status_updated_at = "";
                 }
               });
diff --git a/client/src/stores/completion.ts b/client/src/stores/completion.ts
index ed394905..4bc82f75 100644
--- a/client/src/stores/completion.ts
+++ b/client/src/stores/completion.ts
@@ -43,7 +43,7 @@ export const useCompletionStore = defineStore({
 
       if (courseSessionId) {
         const completionData = await itPost("/api/course/completion/mark/", {
-          page_key: page.translation_key,
+          page_id: page.id,
           completion_status: page.completion_status,
           course_session_id: courseSessionId,
         });
diff --git a/client/src/types.ts b/client/src/types.ts
index 7b523401..aa60c437 100644
--- a/client/src/types.ts
+++ b/client/src/types.ts
@@ -5,7 +5,7 @@ import type { Component } from "vue";
 
 export type LoginMethod = "local" | "sso";
 
-export type CourseCompletionStatus = "unknown" | "fail" | "success";
+export type CourseCompletionStatus = "UNKNOWN" | "FAIL" | "SUCCESS";
 
 export interface BaseCourseWagtailPage {
   readonly id: number;
@@ -169,14 +169,13 @@ export interface Topic extends BaseCourseWagtailPage {
 export type LearningPathChild = Topic | WagtailCircle;
 
 export interface CourseCompletion {
-  id: number;
+  readonly id: number;
   created_at: string;
   updated_at: string;
-  user: number;
-  page_key: string;
-  page_type: string;
-  page_slug: string;
-  course_session: number;
+  readonly user: number;
+  readonly page_id: number;
+  readonly page_type: string;
+  readonly course_session: number;
   completion_status: CourseCompletionStatus;
   additional_json_data: unknown;
 }
diff --git a/server/vbv_lernwelt/course/management/commands/create_default_courses.py b/server/vbv_lernwelt/course/management/commands/create_default_courses.py
index 3023653e..52074a7e 100644
--- a/server/vbv_lernwelt/course/management/commands/create_default_courses.py
+++ b/server/vbv_lernwelt/course/management/commands/create_default_courses.py
@@ -464,19 +464,19 @@ def create_course_uk_de_completion_data(course_session):
     for circle in circles:
         for index, lc in enumerate(circle.get_descendants().type(LearningContent)):
             mark_course_completion(
-                str(lc.translation_key),
-                User.objects.get(email="lina.egger@example.com"),
+                page=lc,
+                user=User.objects.get(email="lina.egger@example.com"),
                 course_session=course_session,
-                completion_status="success",
+                completion_status="SUCCESS",
             )
 
             random_number = random.randint(1, 3)
             if index % random_number == 0:
                 mark_course_completion(
-                    str(lc.translation_key),
-                    User.objects.get(email="michael.meier@example.com"),
+                    page=lc,
+                    user=User.objects.get(email="michael.meier@example.com"),
                     course_session=course_session,
-                    completion_status="success",
+                    completion_status="SUCCESS",
                 )
 
     performance_criteria = (
@@ -486,26 +486,26 @@ def create_course_uk_de_completion_data(course_session):
     )
     for index, pc in enumerate(performance_criteria):
         mark_course_completion(
-            str(pc.translation_key),
-            User.objects.get(email="lina.egger@example.com"),
+            page=pc,
+            user=User.objects.get(email="lina.egger@example.com"),
             course_session=course_session,
-            completion_status="success",
+            completion_status="SUCCESS",
         )
 
         random_number = random.randint(1, 4)
         if index % random_number == 0:
             mark_course_completion(
-                str(pc.translation_key),
-                User.objects.get(email="michael.meier@example.com"),
+                page=pc,
+                user=User.objects.get(email="michael.meier@example.com"),
                 course_session=course_session,
-                completion_status="success",
+                completion_status="SUCCESS",
             )
         if index % random_number == 1:
             mark_course_completion(
-                str(pc.translation_key),
-                User.objects.get(email="michael.meier@example.com"),
+                page=pc,
+                user=User.objects.get(email="michael.meier@example.com"),
                 course_session=course_session,
-                completion_status="fail",
+                completion_status="FAIL",
             )
 
 
diff --git a/server/vbv_lernwelt/course/migrations/0006_auto_20230626_1724.py b/server/vbv_lernwelt/course/migrations/0006_auto_20230626_1724.py
new file mode 100644
index 00000000..9be75406
--- /dev/null
+++ b/server/vbv_lernwelt/course/migrations/0006_auto_20230626_1724.py
@@ -0,0 +1,43 @@
+# Generated by Django 3.2.13 on 2023-06-26 15:24
+
+from django.db import migrations, models
+import django.db.models.deletion
+import vbv_lernwelt.course.models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('wagtailcore', '0083_workflowcontenttype'),
+        ('course', '0005_remove_coursesession_attendance_courses'),
+    ]
+
+    operations = [
+        migrations.RemoveConstraint(
+            model_name='coursecompletion',
+            name='course_completion_unique_user_page_key',
+        ),
+        migrations.RemoveField(
+            model_name='coursecompletion',
+            name='page_key',
+        ),
+        migrations.RemoveField(
+            model_name='coursecompletion',
+            name='page_slug',
+        ),
+        migrations.AddField(
+            model_name='coursecompletion',
+            name='page',
+            field=models.ForeignKey(default=1, on_delete=django.db.models.deletion.CASCADE, to='wagtailcore.page'),
+            preserve_default=False,
+        ),
+        migrations.AlterField(
+            model_name='coursecompletion',
+            name='completion_status',
+            field=models.CharField(choices=[(vbv_lernwelt.course.models.CourseCompletionStatus['SUCCESS'], 'SUCCESS'), (vbv_lernwelt.course.models.CourseCompletionStatus['FAIL'], 'FAIL'), (vbv_lernwelt.course.models.CourseCompletionStatus['UNKNOWN'], 'UNKNOWN')], default='UNKNOWN', max_length=255),
+        ),
+        migrations.AddConstraint(
+            model_name='coursecompletion',
+            constraint=models.UniqueConstraint(fields=('user', 'page', 'course_session'), name='course_completion_unique_user_page_key'),
+        ),
+    ]
diff --git a/server/vbv_lernwelt/course/models.py b/server/vbv_lernwelt/course/models.py
index c2cd39a2..c13dbc45 100644
--- a/server/vbv_lernwelt/course/models.py
+++ b/server/vbv_lernwelt/course/models.py
@@ -1,3 +1,5 @@
+import enum
+
 from django.db import models
 from django.db.models import UniqueConstraint
 from django.utils.text import slugify
@@ -152,6 +154,12 @@ class CoursePage(CourseBasePage):
         return f"{self.title}"
 
 
+class CourseCompletionStatus(enum.Enum):
+    SUCCESS = "SUCCESS"
+    FAIL = "FAIL"
+    UNKNOWN = "UNKNOWN"
+
+
 class CourseCompletion(models.Model):
     created_at = models.DateTimeField(auto_now_add=True)
     updated_at = models.DateTimeField(auto_now=True)
@@ -159,27 +167,24 @@ class CourseCompletion(models.Model):
     user = models.ForeignKey(User, on_delete=models.CASCADE)
 
     # page can logically be a LearningContent or a PerformanceCriteria for now
-    page_key = models.UUIDField()
+    page = models.ForeignKey(Page, on_delete=models.CASCADE)
+
+    # store for convenience and performance...
     page_type = models.CharField(max_length=255, default="", blank=True)
-    page_slug = models.CharField(max_length=255, default="", blank=True)
 
     course_session = models.ForeignKey("course.CourseSession", on_delete=models.CASCADE)
 
     completion_status = models.CharField(
         max_length=255,
-        choices=[
-            ("unknown", "unknown"),
-            ("success", "success"),
-            ("fail", "fail"),
-        ],
-        default="unknown",
+        choices=[(status, status.value) for status in CourseCompletionStatus],
+        default=CourseCompletionStatus.UNKNOWN.value,
     )
     additional_json_data = models.JSONField(default=dict)
 
     class Meta:
         constraints = [
             UniqueConstraint(
-                fields=["user", "page_key", "course_session"],
+                fields=["user", "page", "course_session"],
                 name="course_completion_unique_user_page_key",
             )
         ]
diff --git a/server/vbv_lernwelt/course/serializers.py b/server/vbv_lernwelt/course/serializers.py
index 7ce71f0a..676aeeda 100644
--- a/server/vbv_lernwelt/course/serializers.py
+++ b/server/vbv_lernwelt/course/serializers.py
@@ -43,10 +43,9 @@ class CourseCompletionSerializer(serializers.ModelSerializer):
             "created_at",
             "updated_at",
             "user",
-            "page_key",
+            "page_id",
             "page_type",
-            "page_slug",
-            "course_session",
+            "course_session_id",
             "completion_status",
             "additional_json_data",
         ]
diff --git a/server/vbv_lernwelt/course/services.py b/server/vbv_lernwelt/course/services.py
index 9bfa561d..6ffa1d95 100644
--- a/server/vbv_lernwelt/course/services.py
+++ b/server/vbv_lernwelt/course/services.py
@@ -1,20 +1,23 @@
-from wagtail.models import Page
-
-from vbv_lernwelt.course.models import CourseCompletion
+from vbv_lernwelt.course.models import CourseCompletion, CourseCompletionStatus
 from vbv_lernwelt.learnpath.utils import get_wagtail_type
 
 
-def mark_course_completion(page_key, user, course_session, completion_status="success"):
-    page = Page.objects.get(translation_key=page_key, locale__language_code="de-CH")
-    page_type = get_wagtail_type(page.specific)
-    course = page.specific.get_course()
+def mark_course_completion(
+    page, user, course_session, completion_status=CourseCompletionStatus.SUCCESS.value
+):
+    if completion_status not in CourseCompletionStatus.__members__:
+        raise ValueError(
+            f"Invalid value for CourseCompletionStatus: {completion_status}"
+        )
+
+    # TODO: check if this page can be "marked" by user
     cc, created = CourseCompletion.objects.get_or_create(
-        user=user,
-        page_key=page_key,
+        user_id=user.id,
+        page_id=page.id,
         course_session_id=course_session.id,
     )
-    cc.page_slug = page.slug
-    cc.page_type = page_type
     cc.completion_status = completion_status
+    cc.page_type = get_wagtail_type(page.specific)
+
     cc.save()
     return cc
diff --git a/server/vbv_lernwelt/course/tests/test_completion_api.py b/server/vbv_lernwelt/course/tests/test_completion_api.py
index 4c5db0af..8a81334f 100644
--- a/server/vbv_lernwelt/course/tests/test_completion_api.py
+++ b/server/vbv_lernwelt/course/tests/test_completion_api.py
@@ -18,7 +18,7 @@ class CourseCompletionApiTestCase(APITestCase):
     def setUp(self) -> None:
         create_default_users()
         create_test_course(include_uk=False)
-        self.user = User.objects.get(username="admin")
+        self.user = User.objects.get(username="test-student1@example.com")
         self.cs = CourseSession.objects.create(
             course_id=COURSE_TEST_ID,
             title="Test Lehrgang Session",
@@ -27,20 +27,19 @@ class CourseCompletionApiTestCase(APITestCase):
             course_session=self.cs,
             user=self.user,
         )
-        self.client.login(username="admin", password="test")
+        self.client.force_login(self.user)
 
-    def test_completeLearningContent_works(self):
+    def test_completeLearningContent_happyCase(self):
         learning_content = LearningContentPlaceholder.objects.get(
             title="Fachcheck Reisen"
         )
-        learning_content_key = str(learning_content.translation_key)
 
         mark_url = f"/api/course/completion/mark/"
 
         response = self.client.post(
             mark_url,
             {
-                "page_key": learning_content_key,
+                "page_id": learning_content.id,
                 "course_session_id": self.cs.id,
             },
         )
@@ -49,13 +48,16 @@ class CourseCompletionApiTestCase(APITestCase):
 
         self.assertEqual(response.status_code, 200)
         self.assertEqual(len(response_json), 1)
-        self.assertEqual(response_json[0]["page_key"], learning_content_key)
-        self.assertEqual(response_json[0]["completion_status"], "success")
+        self.assertEqual(response_json[0]["page_id"], learning_content.id)
+        self.assertEqual(
+            response_json[0]["page_type"], "learnpath.LearningContentPlaceholder"
+        )
+        self.assertEqual(response_json[0]["completion_status"], "SUCCESS")
 
         db_entry = CourseCompletion.objects.get(
-            user=self.user, course_session_id=self.cs.id, page_key=learning_content_key
+            user=self.user, course_session_id=self.cs.id, page_id=learning_content.id
         )
-        self.assertEqual(db_entry.completion_status, "success")
+        self.assertEqual(db_entry.completion_status, "SUCCESS")
 
         # test getting the circle data
         response = self.client.get(f"/api/course/completion/{self.cs.id}/")
@@ -65,15 +67,18 @@ class CourseCompletionApiTestCase(APITestCase):
 
         self.assertEqual(response.status_code, 200)
         self.assertEqual(len(response_json), 1)
-        self.assertEqual(response_json[0]["page_key"], learning_content_key)
-        self.assertTrue(response_json[0]["completion_status"], "success")
+        self.assertEqual(response_json[0]["page_id"], learning_content.id)
+        self.assertEqual(
+            response_json[0]["page_type"], "learnpath.LearningContentPlaceholder"
+        )
+        self.assertEqual(response_json[0]["completion_status"], "SUCCESS")
 
         # test with "fail"
         response = self.client.post(
             mark_url,
             {
-                "page_key": learning_content_key,
-                "completion_status": "fail",
+                "page_id": learning_content.id,
+                "completion_status": "FAIL",
                 "course_session_id": self.cs.id,
             },
         )
@@ -81,10 +86,13 @@ class CourseCompletionApiTestCase(APITestCase):
         response_json = response.json()
         self.assertEqual(response.status_code, 200)
         self.assertEqual(len(response_json), 1)
-        self.assertEqual(response_json[0]["page_key"], learning_content_key)
-        self.assertEqual(response_json[0]["completion_status"], "fail")
+        self.assertEqual(response_json[0]["page_id"], learning_content.id)
+        self.assertEqual(
+            response_json[0]["page_type"], "learnpath.LearningContentPlaceholder"
+        )
+        self.assertEqual(response_json[0]["completion_status"], "FAIL")
 
         db_entry = CourseCompletion.objects.get(
-            user=self.user, course_session_id=self.cs.id, page_key=learning_content_key
+            user=self.user, course_session_id=self.cs.id, page_id=learning_content.id
         )
-        self.assertEqual(db_entry.completion_status, "fail")
+        self.assertEqual(db_entry.completion_status, "FAIL")
diff --git a/server/vbv_lernwelt/course/views.py b/server/vbv_lernwelt/course/views.py
index 13089192..1310b731 100644
--- a/server/vbv_lernwelt/course/views.py
+++ b/server/vbv_lernwelt/course/views.py
@@ -89,20 +89,17 @@ def request_course_completion_for_user(request, course_session_id, user_id):
 @api_view(["POST"])
 def mark_course_completion_view(request):
     try:
-        page_key = request.data.get("page_key")
-        completion_status = request.data.get("completion_status", "success")
+        page_id = request.data.get("page_id")
+        completion_status = request.data.get("completion_status", "SUCCESS")
         course_session_id = request.data.get("course_session_id")
-        page = Page.objects.get(translation_key=page_key, locale__language_code="de-CH")
+        page = Page.objects.get(id=page_id)
 
         if not has_course_access_by_page_request(request, page):
             raise PermissionDenied()
 
-        page_type = get_wagtail_type(page.specific)
-        course = page.specific.get_course()
-
         mark_course_completion(
-            page_key,
-            request.user,
+            page=page,
+            user=request.user,
             course_session=CourseSession.objects.get(id=course_session_id),
             completion_status=completion_status,
         )
@@ -117,8 +114,8 @@ def mark_course_completion_view(request):
         logger.debug(
             "mark_course_completion successful",
             label="completion_api",
-            page_key=page_key,
-            page_type=page_type,
+            page_id=page_id,
+            page_type=get_wagtail_type(page.specific),
             page_slug=page.slug,
             page_title=page.title,
             user_id=request.user.id,
diff --git a/server/vbv_lernwelt/course_session/services/attendance.py b/server/vbv_lernwelt/course_session/services/attendance.py
index c52306ed..79ffb62b 100644
--- a/server/vbv_lernwelt/course_session/services/attendance.py
+++ b/server/vbv_lernwelt/course_session/services/attendance.py
@@ -38,12 +38,12 @@ def update_attendance_list(
                 }
             )
             completion_status = (
-                "success"
+                "SUCCESS"
                 if attendance_user.get("status").value == "PRESENT"
-                else "fail"
+                else "FAIL"
             )
             mark_course_completion(
-                page_key=attendance_course.learning_content.translation_key,
+                page=attendance_course.learning_content,
                 user=u,
                 course_session=attendance_course.course_session,
                 completion_status=completion_status,
@@ -63,10 +63,10 @@ def update_attendance_list(
         u = User.objects.filter(id=user_id).first()
         if u is not None:
             mark_course_completion(
-                page_key=attendance_course.learning_content.translation_key,
+                page=attendance_course.learning_content,
                 user=u,
                 course_session=attendance_course.course_session,
-                completion_status="fail",
+                completion_status="FAIL",
             )
 
     return attendance_course
diff --git a/server/vbv_lernwelt/course_session/tests/test_attendance.py b/server/vbv_lernwelt/course_session/tests/test_attendance.py
index 43b4c9b6..841da952 100644
--- a/server/vbv_lernwelt/course_session/tests/test_attendance.py
+++ b/server/vbv_lernwelt/course_session/tests/test_attendance.py
@@ -59,13 +59,8 @@ class AttendanceServicesTestCase(TestCase):
         self.assertEqual(CourseCompletion.objects.count(), 1)
         cc = CourseCompletion.objects.first()
         self.assertEqual(cc.user, student)
-        self.assertEqual(cc.completion_status, "success")
-        self.assertEqual(
-            cc.page_key, self.attendance_course.learning_content.translation_key
-        )
-        self.assertEqual(
-            cc.page_slug, "test-lehrgang-lp-circle-fahrzeug-lc-präsenzkurs-fahrzeug"
-        )
+        self.assertEqual(cc.completion_status, "SUCCESS")
+        self.assertEqual(cc.page_id, self.attendance_course.learning_content.id)
 
     def test_updateAttendanceList_withRemovedUser_willUpdateUserCourseCompletion(self):
         student = User.objects.get(username="test-student1@example.com")
@@ -80,20 +75,15 @@ class AttendanceServicesTestCase(TestCase):
         ]
         self.attendance_course.save()
         mark_course_completion(
-            page_key=self.attendance_course.learning_content.translation_key,
+            page=self.attendance_course.learning_content,
             user=student,
             course_session=self.course_session,
-            completion_status="success",
+            completion_status="SUCCESS",
         )
         update_attendance_list(self.attendance_course, [])
 
         self.assertEqual(CourseCompletion.objects.count(), 1)
         cc = CourseCompletion.objects.first()
         self.assertEqual(cc.user, student)
-        self.assertEqual(cc.completion_status, "fail")
-        self.assertEqual(
-            cc.page_key, self.attendance_course.learning_content.translation_key
-        )
-        self.assertEqual(
-            cc.page_slug, "test-lehrgang-lp-circle-fahrzeug-lc-präsenzkurs-fahrzeug"
-        )
+        self.assertEqual(cc.completion_status, "FAIL")
+        self.assertEqual(cc.page_id, self.attendance_course.learning_content.id)