diff --git a/backend/src/logging/mikroOrmLogger.ts b/backend/src/logging/mikroOrmLogger.ts
index f6907691..9cb797a8 100644
--- a/backend/src/logging/mikroOrmLogger.ts
+++ b/backend/src/logging/mikroOrmLogger.ts
@@ -5,6 +5,25 @@ import { LokiLabels } from 'loki-logger-ts';
 export class MikroOrmLogger extends DefaultLogger {
     private logger: Logger = getLogger();
 
+    static createMessage(namespace: LoggerNamespace, messageArg: string, context?: LogContext): unknown {
+        const labels: LokiLabels = {
+            service: 'ORM',
+        };
+
+        let message: string;
+        if (context?.label) {
+            message = `[${namespace}] (${context.label}) ${messageArg}`;
+        } else {
+            message = `[${namespace}] ${messageArg}`;
+        }
+
+        return {
+            message: message,
+            labels: labels,
+            context: context,
+        };
+    }
+
     log(namespace: LoggerNamespace, message: string, context?: LogContext): void {
         if (!this.isEnabled(namespace, context)) {
             return;
@@ -12,28 +31,28 @@ export class MikroOrmLogger extends DefaultLogger {
 
         switch (namespace) {
             case 'query':
-                this.logger.debug(this.createMessage(namespace, message, context));
+                this.logger.debug(MikroOrmLogger.createMessage(namespace, message, context));
                 break;
             case 'query-params':
                 // TODO Which log level should this be?
-                this.logger.info(this.createMessage(namespace, message, context));
+                this.logger.info(MikroOrmLogger.createMessage(namespace, message, context));
                 break;
             case 'schema':
-                this.logger.info(this.createMessage(namespace, message, context));
+                this.logger.info(MikroOrmLogger.createMessage(namespace, message, context));
                 break;
             case 'discovery':
-                this.logger.debug(this.createMessage(namespace, message, context));
+                this.logger.debug(MikroOrmLogger.createMessage(namespace, message, context));
                 break;
             case 'info':
-                this.logger.info(this.createMessage(namespace, message, context));
+                this.logger.info(MikroOrmLogger.createMessage(namespace, message, context));
                 break;
             case 'deprecated':
-                this.logger.warn(this.createMessage(namespace, message, context));
+                this.logger.warn(MikroOrmLogger.createMessage(namespace, message, context));
                 break;
             default:
                 switch (context?.level) {
                     case 'info':
-                        this.logger.info(this.createMessage(namespace, message, context));
+                        this.logger.info(MikroOrmLogger.createMessage(namespace, message, context));
                         break;
                     case 'warning':
                         this.logger.warn(message);
@@ -47,23 +66,4 @@ export class MikroOrmLogger extends DefaultLogger {
                 }
         }
     }
-
-    private createMessage(namespace: LoggerNamespace, messageArg: string, context?: LogContext): unknown {
-        const labels: LokiLabels = {
-            service: 'ORM',
-        };
-
-        let message: string;
-        if (context?.label) {
-            message = `[${namespace}] (${context?.label}) ${messageArg}`;
-        } else {
-            message = `[${namespace}] ${messageArg}`;
-        }
-
-        return {
-            message: message,
-            labels: labels,
-            context: context,
-        };
-    }
 }
diff --git a/backend/src/services/learning-objects/processing/audio/audio-processor.ts b/backend/src/services/learning-objects/processing/audio/audio-processor.ts
index 592669d5..227eae13 100644
--- a/backend/src/services/learning-objects/processing/audio/audio-processor.ts
+++ b/backend/src/services/learning-objects/processing/audio/audio-processor.ts
@@ -14,7 +14,7 @@ class AudioProcessor extends StringProcessor {
         super(DwengoContentType.AUDIO_MPEG);
     }
 
-    protected renderFn(audioUrl: string): string {
+    override renderFn(audioUrl: string): string {
         return DOMPurify.sanitize(`<audio controls>
             <source src="${audioUrl}" type=${type}>
             Your browser does not support the audio element.
diff --git a/backend/src/services/learning-objects/processing/gift/question-renderers/category-question-renderer.ts b/backend/src/services/learning-objects/processing/gift/question-renderers/category-question-renderer.ts
index 256a38a7..13311e6e 100644
--- a/backend/src/services/learning-objects/processing/gift/question-renderers/category-question-renderer.ts
+++ b/backend/src/services/learning-objects/processing/gift/question-renderers/category-question-renderer.ts
@@ -3,7 +3,7 @@ import { Category } from 'gift-pegjs';
 import { ProcessingError } from '../../processing-error.js';
 
 export class CategoryQuestionRenderer extends GIFTQuestionRenderer<Category> {
-    render(_question: Category, _questionNumber: number): string {
+    override render(_question: Category, _questionNumber: number): string {
         throw new ProcessingError("The question type 'Category' is not supported yet!");
     }
 }
diff --git a/backend/src/services/learning-objects/processing/gift/question-renderers/description-question-renderer.ts b/backend/src/services/learning-objects/processing/gift/question-renderers/description-question-renderer.ts
index 7bab255f..9de260e3 100644
--- a/backend/src/services/learning-objects/processing/gift/question-renderers/description-question-renderer.ts
+++ b/backend/src/services/learning-objects/processing/gift/question-renderers/description-question-renderer.ts
@@ -3,7 +3,7 @@ import { Description } from 'gift-pegjs';
 import { ProcessingError } from '../../processing-error.js';
 
 export class DescriptionQuestionRenderer extends GIFTQuestionRenderer<Description> {
-    render(_question: Description, _questionNumber: number): string {
+    override render(_question: Description, _questionNumber: number): string {
         throw new ProcessingError("The question type 'Description' is not supported yet!");
     }
 }
diff --git a/backend/src/services/learning-objects/processing/gift/question-renderers/essay-question-renderer.ts b/backend/src/services/learning-objects/processing/gift/question-renderers/essay-question-renderer.ts
index 987fbcaf..d27fef57 100644
--- a/backend/src/services/learning-objects/processing/gift/question-renderers/essay-question-renderer.ts
+++ b/backend/src/services/learning-objects/processing/gift/question-renderers/essay-question-renderer.ts
@@ -2,7 +2,7 @@ import { GIFTQuestionRenderer } from './gift-question-renderer.js';
 import { Essay } from 'gift-pegjs';
 
 export class EssayQuestionRenderer extends GIFTQuestionRenderer<Essay> {
-    render(question: Essay, questionNumber: number): string {
+    override render(question: Essay, questionNumber: number): string {
         let renderedHtml = '';
         if (question.title) {
             renderedHtml += `<h2 class='gift-title' id='gift-q${questionNumber}-title'>${question.title}</h2>\n`;
diff --git a/backend/src/services/learning-objects/processing/gift/question-renderers/matching-question-renderer.ts b/backend/src/services/learning-objects/processing/gift/question-renderers/matching-question-renderer.ts
index 21713920..9642a3cb 100644
--- a/backend/src/services/learning-objects/processing/gift/question-renderers/matching-question-renderer.ts
+++ b/backend/src/services/learning-objects/processing/gift/question-renderers/matching-question-renderer.ts
@@ -3,7 +3,7 @@ import { Matching } from 'gift-pegjs';
 import { ProcessingError } from '../../processing-error.js';
 
 export class MatchingQuestionRenderer extends GIFTQuestionRenderer<Matching> {
-    render(_question: Matching, _questionNumber: number): string {
+    override render(_question: Matching, _questionNumber: number): string {
         throw new ProcessingError("The question type 'Matching' is not supported yet!");
     }
 }
diff --git a/backend/src/services/learning-objects/processing/gift/question-renderers/multiple-choice-question-renderer.ts b/backend/src/services/learning-objects/processing/gift/question-renderers/multiple-choice-question-renderer.ts
index 39846c51..9b09004f 100644
--- a/backend/src/services/learning-objects/processing/gift/question-renderers/multiple-choice-question-renderer.ts
+++ b/backend/src/services/learning-objects/processing/gift/question-renderers/multiple-choice-question-renderer.ts
@@ -2,7 +2,7 @@ import { GIFTQuestionRenderer } from './gift-question-renderer.js';
 import { MultipleChoice } from 'gift-pegjs';
 
 export class MultipleChoiceQuestionRenderer extends GIFTQuestionRenderer<MultipleChoice> {
-    render(question: MultipleChoice, questionNumber: number): string {
+    override render(question: MultipleChoice, questionNumber: number): string {
         let renderedHtml = '';
         if (question.title) {
             renderedHtml += `<h2 class='gift-title' id='gift-q${questionNumber}-title'>${question.title}</h2>\n`;
diff --git a/backend/src/services/learning-objects/processing/gift/question-renderers/numerical-question-renderer.ts b/backend/src/services/learning-objects/processing/gift/question-renderers/numerical-question-renderer.ts
index 2286cd42..3338c1e3 100644
--- a/backend/src/services/learning-objects/processing/gift/question-renderers/numerical-question-renderer.ts
+++ b/backend/src/services/learning-objects/processing/gift/question-renderers/numerical-question-renderer.ts
@@ -3,7 +3,7 @@ import { Numerical } from 'gift-pegjs';
 import { ProcessingError } from '../../processing-error.js';
 
 export class NumericalQuestionRenderer extends GIFTQuestionRenderer<Numerical> {
-    render(_question: Numerical, _questionNumber: number): string {
+    override render(_question: Numerical, _questionNumber: number): string {
         throw new ProcessingError("The question type 'Numerical' is not supported yet!");
     }
 }
diff --git a/backend/src/services/learning-objects/processing/gift/question-renderers/short-question-renderer.ts b/backend/src/services/learning-objects/processing/gift/question-renderers/short-question-renderer.ts
index 1e5527e0..68656422 100644
--- a/backend/src/services/learning-objects/processing/gift/question-renderers/short-question-renderer.ts
+++ b/backend/src/services/learning-objects/processing/gift/question-renderers/short-question-renderer.ts
@@ -3,7 +3,7 @@ import { ShortAnswer } from 'gift-pegjs';
 import { ProcessingError } from '../../processing-error.js';
 
 export class ShortQuestionRenderer extends GIFTQuestionRenderer<ShortAnswer> {
-    render(_question: ShortAnswer, _questionNumber: number): string {
+    override render(_question: ShortAnswer, _questionNumber: number): string {
         throw new ProcessingError("The question type 'ShortAnswer' is not supported yet!");
     }
 }
diff --git a/backend/src/services/learning-objects/processing/gift/question-renderers/true-false-question-renderer.ts b/backend/src/services/learning-objects/processing/gift/question-renderers/true-false-question-renderer.ts
index fabbc634..0c390ad9 100644
--- a/backend/src/services/learning-objects/processing/gift/question-renderers/true-false-question-renderer.ts
+++ b/backend/src/services/learning-objects/processing/gift/question-renderers/true-false-question-renderer.ts
@@ -3,7 +3,7 @@ import { TrueFalse } from 'gift-pegjs';
 import { ProcessingError } from '../../processing-error.js';
 
 export class TrueFalseQuestionRenderer extends GIFTQuestionRenderer<TrueFalse> {
-    render(_question: TrueFalse, _questionNumber: number): string {
+    override render(_question: TrueFalse, _questionNumber: number): string {
         throw new ProcessingError("The question type 'TrueFalse' is not supported yet!");
     }
 }
diff --git a/backend/src/services/learning-objects/processing/markdown/markdown-processor.ts b/backend/src/services/learning-objects/processing/markdown/markdown-processor.ts
index dbbf2a37..6486aca5 100644
--- a/backend/src/services/learning-objects/processing/markdown/markdown-processor.ts
+++ b/backend/src/services/learning-objects/processing/markdown/markdown-processor.ts
@@ -15,11 +15,20 @@ class MarkdownProcessor extends StringProcessor {
         super(DwengoContentType.TEXT_MARKDOWN);
     }
 
+    static replaceLinks(html: string): string {
+        const proc = new InlineImageProcessor();
+        html = html.replace(
+            /<img.*?src="(.*?)".*?(alt="(.*?)")?.*?(title="(.*?)")?.*?>/g,
+            (_match: string, src: string, _alt: string, _altText: string, _title: string, _titleText: string) => proc.render(src)
+        );
+        return html;
+    }
+
     override renderFn(mdText: string): string {
         try {
             marked.use({ renderer: dwengoMarkedRenderer });
             const html = marked(mdText, { async: false });
-            return this.replaceLinks(html); // Replace html image links path
+            return MarkdownProcessor.replaceLinks(html); // Replace html image links path
         } catch (e: unknown) {
             if (e instanceof YAMLException) {
                 throw new ProcessingError(e.message);
@@ -28,15 +37,6 @@ class MarkdownProcessor extends StringProcessor {
             throw new ProcessingError('Unknown error while processing markdown: ' + e);
         }
     }
-
-    replaceLinks(html: string): string {
-        const proc = new InlineImageProcessor();
-        html = html.replace(
-            /<img.*?src="(.*?)".*?(alt="(.*?)")?.*?(title="(.*?)")?.*?>/g,
-            (_match: string, src: string, _alt: string, _altText: string, _title: string, _titleText: string) => proc.render(src)
-        );
-        return html;
-    }
 }
 
 export { MarkdownProcessor };
diff --git a/eslint.config.ts b/eslint.config.ts
index 7c606d0c..0541aa4a 100644
--- a/eslint.config.ts
+++ b/eslint.config.ts
@@ -35,6 +35,9 @@ export default [
             '@typescript-eslint/array-type': 'warn',
             '@typescript-eslint/await-thenable': 'error',
 
+            'class-methods-use-this': 'off',
+            '@typescript-eslint/class-methods-use-this': [ 'error', { ignoreOverrideMethods: true } ],
+
             'consistent-return': 'off',
             '@typescript-eslint/consistent-return': 'off',
             '@typescript-eslint/consistent-type-assertions': 'error',