diff --git a/backend/eslint.config.ts b/backend/eslint.config.ts
index 6b696021..f5f225b2 100644
--- a/backend/eslint.config.ts
+++ b/backend/eslint.config.ts
@@ -8,14 +8,4 @@ export default [
             globals: globals.node,
         },
     },
-
-    {
-        files: ['tests/**/*.ts'],
-        languageOptions: {
-            globals: globals.node,
-        },
-        rules: {
-            'no-console': 'off',
-        },
-    },
 ];
diff --git a/backend/package.json b/backend/package.json
index 4e3b890d..c08fb1dc 100644
--- a/backend/package.json
+++ b/backend/package.json
@@ -11,7 +11,7 @@
         "format": "prettier --write src/",
         "format-check": "prettier --check src/",
         "lint": "eslint . --fix",
-        "test:unit": "vitest"
+        "test:unit": "vitest --run"
     },
     "dependencies": {
         "@mikro-orm/core": "6.4.9",
diff --git a/backend/src/controllers/assignments.ts b/backend/src/controllers/assignments.ts
index e1a39448..c66e8799 100644
--- a/backend/src/controllers/assignments.ts
+++ b/backend/src/controllers/assignments.ts
@@ -2,7 +2,7 @@ import { Request, Response } from 'express';
 import { createAssignment, getAllAssignments, getAssignment, getAssignmentsSubmissions } from '../services/assignments.js';
 import { AssignmentDTO } from '../interfaces/assignment.js';
 
-// Typescript is annoy with with parameter forwarding from class.ts
+// Typescript is annoying with parameter forwarding from class.ts
 interface AssignmentParams {
     classid: string;
     id: string;
diff --git a/backend/src/controllers/groups.ts b/backend/src/controllers/groups.ts
index 787d3761..7b1f5a1e 100644
--- a/backend/src/controllers/groups.ts
+++ b/backend/src/controllers/groups.ts
@@ -80,7 +80,7 @@ export async function getGroupSubmissionsHandler(req: Request, res: Response): P
         return;
     }
 
-    const groupId = Number(req.params.groupid!); // Can't be undefined
+    const groupId = Number(req.params.groupid); // Can't be undefined
 
     if (isNaN(groupId)) {
         res.status(400).json({ error: 'Group id must be a number' });
diff --git a/backend/src/controllers/themes.ts b/backend/src/controllers/themes.ts
index 1ef113cd..37539690 100644
--- a/backend/src/controllers/themes.ts
+++ b/backend/src/controllers/themes.ts
@@ -3,18 +3,16 @@ import { themes } from '../data/themes.js';
 import { loadTranslations } from '../util/translation-helper.js';
 
 interface Translations {
-    curricula_page: {
-        [key: string]: { title: string; description?: string };
-    };
+    curricula_page: Record<string, { title: string; description?: string }>;
 }
 
 export function getThemes(req: Request, res: Response): void {
-    const language = (req.query.language as string)?.toLowerCase() || 'nl';
+    const language = (req.query.language as string).toLowerCase() || 'nl';
     const translations = loadTranslations<Translations>(language);
     const themeList = themes.map((theme) => ({
         key: theme.title,
-        title: translations.curricula_page[theme.title]?.title || theme.title,
-        description: translations.curricula_page[theme.title]?.description,
+        title: translations.curricula_page[theme.title].title || theme.title,
+        description: translations.curricula_page[theme.title].description,
         image: `https://dwengo.org/images/curricula/logo_${theme.title}.png`,
     }));
 
diff --git a/backend/src/services/learning-paths/database-learning-path-provider.ts b/backend/src/services/learning-paths/database-learning-path-provider.ts
index c8ab41ca..3d883ef2 100644
--- a/backend/src/services/learning-paths/database-learning-path-provider.ts
+++ b/backend/src/services/learning-paths/database-learning-path-provider.ts
@@ -25,7 +25,7 @@ async function getLearningObjectsForNodes(nodes: LearningPathNode[]): Promise<Ma
                         version: node.version,
                         language: node.language,
                     })
-                    .then((learningObject) => ([node, learningObject] as [LearningPathNode, FilteredLearningObject | null]))
+                    .then((learningObject) => [node, learningObject] as [LearningPathNode, FilteredLearningObject | null])
             )
         )
     );
diff --git a/backend/tests/data/content/learning-path-repository.test.ts b/backend/tests/data/content/learning-path-repository.test.ts
index 8dbff3c1..4424fced 100644
--- a/backend/tests/data/content/learning-path-repository.test.ts
+++ b/backend/tests/data/content/learning-path-repository.test.ts
@@ -10,7 +10,7 @@ import { Language } from '../../../src/entities/content/language.js';
 function expectToHaveFoundPrecisely(expected: LearningPath, result: LearningPath[]): void {
     expect(result).toHaveProperty('length');
     expect(result.length).toBe(1);
-    expectToBeCorrectEntity({ entity: result[0]! }, { entity: expected });
+    expectToBeCorrectEntity({ entity: result[0] }, { entity: expected });
 }
 
 function expectToHaveFoundNothing(result: LearningPath[]): void {
diff --git a/backend/tests/services/learning-path/database-learning-path-provider.test.ts b/backend/tests/services/learning-path/database-learning-path-provider.test.ts
index 8d9dd530..a5943f5f 100644
--- a/backend/tests/services/learning-path/database-learning-path-provider.test.ts
+++ b/backend/tests/services/learning-path/database-learning-path-provider.test.ts
@@ -46,8 +46,6 @@ async function initPersonalizationTestData(): Promise<{
     await learningObjectRepo.save(learningContent.extraExerciseObject);
     await learningPathRepo.save(learningContent.learningPath);
 
-    console.log(await getSubmissionRepository().findAll({}));
-
     const studentA = studentRepo.create({
         username: 'student_a',
         firstName: 'Aron',
diff --git a/eslint.config.ts b/eslint.config.ts
index 0541aa4a..ad4a831f 100644
--- a/eslint.config.ts
+++ b/eslint.config.ts
@@ -32,12 +32,23 @@ export default [
             reportUnusedInlineConfigs: 'error',
         },
         rules: {
+            // All @typescript-eslint configuration options are listed.
+            // If the rules are commented, they are configured by the inherited configurations.
+
+            '@typescript-eslint/adjacent-overload-signatures': 'warn',
             '@typescript-eslint/array-type': 'warn',
             '@typescript-eslint/await-thenable': 'error',
-
+            '@typescript-eslint/ban-ts-comment': [
+                'error',
+                { minimumDescriptionLength: 10 },
+            ],
+            '@typescript-eslint/ban-tslint-comment': 'error',
+            'camelcase': 'off',
+            '@typescript-eslint/class-literal-property-style': 'warn',
             'class-methods-use-this': 'off',
             '@typescript-eslint/class-methods-use-this': [ 'error', { ignoreOverrideMethods: true } ],
-
+            '@typescript-eslint/consistent-generic-constructors': 'warn',
+            '@typescript-eslint/consistent-indexed-object-style': 'error',
             'consistent-return': 'off',
             '@typescript-eslint/consistent-return': 'off',
             '@typescript-eslint/consistent-type-assertions': 'error',
@@ -46,9 +57,13 @@ export default [
             '@typescript-eslint/consistent-type-imports': 'off',
             'default-param-last': 'off',
             '@typescript-eslint/default-param-last': 'error',
-
+            'dot-notation': 'off',
+            '@typescript-eslint/dot-notation': 'warn',
             '@typescript-eslint/explicit-function-return-type': 'warn',
-
+            '@typescript-eslint/explicit-member-accessibility': 'off',
+            '@typescript-eslint/explicit-module-boundary-types': 'warn',
+            'init-declarations': 'off',
+            '@typescript-eslint/init-declarations': 'off',
             'max-params': 'off',
             '@typescript-eslint/max-params': ['error', { 'max': 6 }],
             '@typescript-eslint/member-ordering': 'warn',
@@ -76,22 +91,41 @@ export default [
             'no-array-constructor': 'off',
             '@typescript-eslint/no-array-constructor': 'error',
             '@typescript-eslint/no-array-delete': 'error',
-
+            '@typescript-eslint/no-base-to-string': 'off',
+            '@typescript-eslint/no-confusing-non-null-assertion': 'error',
+            '@typescript-eslint/no-confusing-void-expression': 'error',
+            '@typescript-eslint/no-deprecated': 'error',
             'no-dupe-class-members': 'off',
             '@typescript-eslint/no-dupe-class-members': 'off',
             '@typescript-eslint/no-duplicate-enum-values': 'error',
             'no-duplicate-imports': 'off',
             '@typescript-eslint/no-duplicate-type-constituents': 'off',
-
-            // 'no-empty-function': 'off',
+            '@typescript-eslint/no-dynamic-delete': 'error',
+            'no-empty-function': 'off',
             '@typescript-eslint/no-empty-function': 'error',
-
+            '@typescript-eslint/no-empty-interface': 'off',
+            '@typescript-eslint/no-empty-object-type': 'error',
+            '@typescript-eslint/no-explicit-any': 'warn', // Once in production, this should be an error.
+            '@typescript-eslint/no-extra-non-null-assertion': 'error',
+            '@typescript-eslint/no-extraneous-class': 'error',
+            '@typescript-eslint/no-floating-promises': 'error',
             '@typescript-eslint/no-for-in-array': 'error',
-
+            'no-implied-eval': 'off',
+            '@typescript-eslint/no-implied-eval': 'error',
+            '@typescript-eslint/no-import-type-side-effects': 'error',
             '@typescript-eslint/no-inferrable-types': 'warn',
-
+            'no-invalid-this': 'off',
+            '@typescript-eslint/no-invalid-this': 'off',
+            '@typescript-eslint/no-invalid-void-type': 'error',
             'no-loop-func': 'off',
             '@typescript-eslint/no-loop-func': 'error',
+            'no-loss-of-precision': 'off',
+            '@typescript-eslint/no-loss-of-precision': 'off',
+            'no-magic-numbers': 'off',
+            '@typescript-eslint/no-magic-numbers': 'off',
+
+            'no-redeclare': 'off',
+            '@typescript-eslint/no-redeclare': 'off',
 
             '@typescript-eslint/no-type-alias': 'off',
 
@@ -149,7 +183,6 @@ export default [
             curly: 'error',
             'default-case': 'error',
             'default-case-last': 'error',
-            'dot-notation': 'warn',
             eqeqeq: 'error',
             'func-names': 'warn',
             'func-style': ['warn', 'declaration'],