diff --git a/ui/package.json b/ui/package.json
index 10979cd..6235feb 100644
--- a/ui/package.json
+++ b/ui/package.json
@@ -15,9 +15,9 @@
     "@vitejs/plugin-react": "^4.7.0",
     "axios": "^1.11.0",
     "detect-browser": "^5.3.0",
-    "mobx": "^5.15.6",
-    "mobx-react": "^6.3.0",
-    "mobx-utils": "^5.6.1",
+    "mobx": "^6.13.7",
+    "mobx-react": "^9.2.0",
+    "mobx-utils": "^6.1.1",
     "notifyjs": "^3.0.0",
     "notistack": "^3.0.2",
     "react": "^19.1.1",
diff --git a/ui/src/CurrentUser.ts b/ui/src/CurrentUser.ts
index 34e2e0a..39409cd 100644
--- a/ui/src/CurrentUser.ts
+++ b/ui/src/CurrentUser.ts
@@ -2,7 +2,7 @@ import axios, {AxiosError, AxiosResponse} from 'axios';
 import * as config from './config';
 import {detect} from 'detect-browser';
 import {SnackReporter} from './snack/SnackManager';
-import {observable} from 'mobx';
+import {observable, makeObservable} from 'mobx';
 import {IClient, IUser} from './types';
 
 const tokenKey = 'gotify-login-key';
@@ -11,16 +11,19 @@ export class CurrentUser {
     private tokenCache: string | null = null;
     private reconnectTimeoutId: number | null = null;
     private reconnectTime = 7500;
-    @observable
     public loggedIn = false;
-    @observable
     public authenticating = true;
-    @observable
     public user: IUser = {name: 'unknown', admin: false, id: -1};
-    @observable
     public connectionErrorMessage: string | null = null;
 
-    public constructor(private readonly snack: SnackReporter) {}
+    public constructor(private readonly snack: SnackReporter) {
+        makeObservable(this, {
+            loggedIn: observable,
+            authenticating: observable,
+            user: observable,
+            connectionErrorMessage: observable,
+        });
+    }
 
     public token = (): string => {
         if (this.tokenCache !== null) {
diff --git a/ui/src/application/AppStore.ts b/ui/src/application/AppStore.ts
index dc5d5f2..9ffacb3 100644
--- a/ui/src/application/AppStore.ts
+++ b/ui/src/application/AppStore.ts
@@ -1,7 +1,7 @@
 import {BaseStore} from '../common/BaseStore';
 import axios from 'axios';
 import * as config from '../config';
-import {action} from 'mobx';
+import {action, makeObservable} from 'mobx';
 import {SnackReporter} from '../snack/SnackManager';
 import {IApplication} from '../types';
 
@@ -10,6 +10,12 @@ export class AppStore extends BaseStore<IApplication> {
 
     public constructor(private readonly snack: SnackReporter) {
         super();
+
+        makeObservable(this, {
+            uploadImage: action,
+            update: action,
+            create: action,
+        });
     }
 
     protected requestItems = (): Promise<IApplication[]> =>
@@ -23,7 +29,6 @@ export class AppStore extends BaseStore<IApplication> {
             return this.snack('Application deleted');
         });
 
-    @action
     public uploadImage = async (id: number, file: Blob): Promise<void> => {
         const formData = new FormData();
         formData.append('file', file);
@@ -34,7 +39,6 @@ export class AppStore extends BaseStore<IApplication> {
         this.snack('Application image updated');
     };
 
-    @action
     public update = async (
         id: number,
         name: string,
@@ -50,7 +54,6 @@ export class AppStore extends BaseStore<IApplication> {
         this.snack('Application updated');
     };
 
-    @action
     public create = async (
         name: string,
         description: string,
diff --git a/ui/src/client/ClientStore.ts b/ui/src/client/ClientStore.ts
index cc63b6e..3e7edd7 100644
--- a/ui/src/client/ClientStore.ts
+++ b/ui/src/client/ClientStore.ts
@@ -1,13 +1,19 @@
 import {BaseStore} from '../common/BaseStore';
 import axios from 'axios';
 import * as config from '../config';
-import {action} from 'mobx';
+import {action, makeObservable} from 'mobx';
 import {SnackReporter} from '../snack/SnackManager';
 import {IClient} from '../types';
 
 export class ClientStore extends BaseStore<IClient> {
     public constructor(private readonly snack: SnackReporter) {
         super();
+
+        makeObservable(this, {
+            update: action,
+            createNoNotifcation: action,
+            create: action,
+        });
     }
 
     protected requestItems = (): Promise<IClient[]> =>
@@ -19,21 +25,18 @@ export class ClientStore extends BaseStore<IClient> {
             .then(() => this.snack('Client deleted'));
     }
 
-    @action
     public update = async (id: number, name: string): Promise<void> => {
         await axios.put(`${config.get('url')}client/${id}`, {name});
         await this.refresh();
         this.snack('Client updated');
     };
 
-    @action
     public createNoNotifcation = async (name: string): Promise<IClient> => {
         const client = await axios.post(`${config.get('url')}client`, {name});
         await this.refresh();
         return client.data;
     };
 
-    @action
     public create = async (name: string): Promise<void> => {
         await this.createNoNotifcation(name);
         this.snack('Client added');
diff --git a/ui/src/common/BaseStore.ts b/ui/src/common/BaseStore.ts
index 4b2b4ee..7601400 100644
--- a/ui/src/common/BaseStore.ts
+++ b/ui/src/common/BaseStore.ts
@@ -1,4 +1,4 @@
-import {action, observable} from 'mobx';
+import {action, observable, makeObservable} from 'mobx';
 
 interface HasID {
     id: number;
@@ -12,25 +12,21 @@ export interface IClearable {
  * Base implementation for handling items with ids.
  */
 export abstract class BaseStore<T extends HasID> implements IClearable {
-    @observable
     protected items: T[] = [];
 
     protected abstract requestItems(): Promise<T[]>;
 
     protected abstract requestDelete(id: number): Promise<void>;
 
-    @action
     public remove = async (id: number): Promise<void> => {
         await this.requestDelete(id);
         await this.refresh();
     };
 
-    @action
     public refresh = async (): Promise<void> => {
         this.items = await this.requestItems().then((items) => items || []);
     };
 
-    @action
     public refreshIfMissing = async (id: number): Promise<void> => {
         if (this.getByIDOrUndefined(id) === undefined) {
             await this.refresh();
@@ -50,8 +46,18 @@ export abstract class BaseStore<T extends HasID> implements IClearable {
 
     public getItems = (): T[] => this.items;
 
-    @action
     public clear = (): void => {
         this.items = [];
     };
+
+    constructor() {
+        // eslint-disable-next-line
+        makeObservable<BaseStore<any>, 'items'>(this, {
+            items: observable,
+            remove: action,
+            refresh: action,
+            refreshIfMissing: action,
+            clear: action,
+        });
+    }
 }
diff --git a/ui/src/message/MessagesStore.ts b/ui/src/message/MessagesStore.ts
index 24ff431..406fcb3 100644
--- a/ui/src/message/MessagesStore.ts
+++ b/ui/src/message/MessagesStore.ts
@@ -1,5 +1,5 @@
 import {BaseStore} from '../common/BaseStore';
-import {action, IObservableArray, observable, reaction} from 'mobx';
+import {action, IObservableArray, observable, reaction, makeObservable} from 'mobx';
 import axios, {AxiosResponse} from 'axios';
 import * as config from '../config';
 import {createTransformer} from 'mobx-utils';
@@ -16,7 +16,6 @@ interface MessagesState {
 }
 
 export class MessagesStore {
-    @observable
     private state: Record<string, MessagesState> = {};
 
     private loading = false;
@@ -25,6 +24,16 @@ export class MessagesStore {
         private readonly appStore: BaseStore<IApplication>,
         private readonly snack: SnackReporter
     ) {
+        makeObservable<MessagesStore, 'state'>(this, {
+            state: observable,
+            loadMore: action,
+            publishSingleMessage: action,
+            removeByApp: action,
+            removeSingle: action,
+            clearAll: action,
+            refreshByApp: action,
+        });
+
         reaction(() => appStore.getItems(), this.createEmptyStatesForApps);
     }
 
@@ -39,7 +48,6 @@ export class MessagesStore {
 
     public canLoadMore = (appId: number) => this.stateOf(appId, /*create*/ false).hasMore;
 
-    @action
     public loadMore = async (appId: number) => {
         const state = this.stateOf(appId);
         if (!state.hasMore || this.loading) {
@@ -59,7 +67,6 @@ export class MessagesStore {
         return Promise.resolve();
     };
 
-    @action
     public publishSingleMessage = (message: IMessage) => {
         if (this.exists(AllMessages)) {
             this.stateOf(AllMessages).messages.unshift(message);
@@ -69,7 +76,6 @@ export class MessagesStore {
         }
     };
 
-    @action
     public removeByApp = async (appId: number) => {
         if (appId === AllMessages) {
             await axios.delete(config.get('url') + 'message');
@@ -84,7 +90,6 @@ export class MessagesStore {
         await this.loadMore(appId);
     };
 
-    @action
     public removeSingle = async (message: IMessage) => {
         await axios.delete(config.get('url') + 'message/' + message.id);
         if (this.exists(AllMessages)) {
@@ -96,13 +101,11 @@ export class MessagesStore {
         this.snack('Message deleted');
     };
 
-    @action
     public clearAll = () => {
         this.state = {};
         this.createEmptyStatesForApps(this.appStore.getItems());
     };
 
-    @action
     public refreshByApp = async (appId: number) => {
         this.clearAll();
         this.loadMore(appId);
diff --git a/ui/src/plugin/PluginStore.ts b/ui/src/plugin/PluginStore.ts
index 363af47..920366b 100644
--- a/ui/src/plugin/PluginStore.ts
+++ b/ui/src/plugin/PluginStore.ts
@@ -1,5 +1,5 @@
 import axios from 'axios';
-import {action} from 'mobx';
+import {action, makeObservable} from 'mobx';
 import {BaseStore} from '../common/BaseStore';
 import * as config from '../config';
 import {SnackReporter} from '../snack/SnackManager';
@@ -10,6 +10,11 @@ export class PluginStore extends BaseStore<IPlugin> {
 
     public constructor(private readonly snack: SnackReporter) {
         super();
+
+        makeObservable(this, {
+            changeConfig: action,
+            changeEnabledState: action,
+        });
     }
 
     public requestConfig = (id: number): Promise<string> =>
@@ -31,7 +36,6 @@ export class PluginStore extends BaseStore<IPlugin> {
         return id === -1 ? 'All Plugins' : plugin !== undefined ? plugin.name : 'unknown';
     };
 
-    @action
     public changeConfig = async (id: number, newConfig: string): Promise<void> => {
         await axios.post(`${config.get('url')}plugin/${id}/config`, newConfig, {
             headers: {'content-type': 'application/x-yaml'},
@@ -40,7 +44,6 @@ export class PluginStore extends BaseStore<IPlugin> {
         await this.refresh();
     };
 
-    @action
     public changeEnabledState = async (id: number, enabled: boolean): Promise<void> => {
         await axios.post(`${config.get('url')}plugin/${id}/${enabled ? 'enable' : 'disable'}`);
         this.snack(`Plugin ${enabled ? 'enabled' : 'disabled'}`);
diff --git a/ui/src/user/UserStore.ts b/ui/src/user/UserStore.ts
index dc42f37..5068b69 100644
--- a/ui/src/user/UserStore.ts
+++ b/ui/src/user/UserStore.ts
@@ -1,13 +1,18 @@
 import {BaseStore} from '../common/BaseStore';
 import axios from 'axios';
 import * as config from '../config';
-import {action} from 'mobx';
+import {action, makeObservable} from 'mobx';
 import {SnackReporter} from '../snack/SnackManager';
 import {IUser} from '../types';
 
 export class UserStore extends BaseStore<IUser> {
     constructor(private readonly snack: SnackReporter) {
         super();
+
+        makeObservable(this, {
+            create: action,
+            update: action,
+        });
     }
 
     protected requestItems = (): Promise<IUser[]> =>
@@ -19,14 +24,12 @@ export class UserStore extends BaseStore<IUser> {
             .then(() => this.snack('User deleted'));
     }
 
-    @action
     public create = async (name: string, pass: string, admin: boolean) => {
         await axios.post(`${config.get('url')}user`, {name, pass, admin});
         await this.refresh();
         this.snack('User created');
     };
 
-    @action
     public update = async (id: number, name: string, pass: string | null, admin: boolean) => {
         await axios.post(config.get('url') + 'user/' + id, {name, pass, admin});
         await this.refresh();
diff --git a/ui/tsconfig.json b/ui/tsconfig.json
index 892284f..d5e4e10 100644
--- a/ui/tsconfig.json
+++ b/ui/tsconfig.json
@@ -16,7 +16,6 @@
     "strictNullChecks": true,
     "noUnusedLocals": true,
     "allowSyntheticDefaultImports": true,
-    "experimentalDecorators": true,
     "skipLibCheck": true,
     "esModuleInterop": true,
     "strict": true,
diff --git a/ui/vite.config.ts b/ui/vite.config.ts
index 769069a..639f6cf 100644
--- a/ui/vite.config.ts
+++ b/ui/vite.config.ts
@@ -10,15 +10,7 @@ export default defineConfig({
         sourcemap: false,
         assetsDir: 'static',
     },
-    plugins: [
-        react({
-            babel: {
-                parserOpts: {
-                    plugins: ['decorators-legacy'],
-                },
-            },
-        }),
-    ],
+    plugins: [react()],
     define: {
         // Some libraries use the global object, even though it doesn't exist in the browser.
         // Alternatively, we could add `<script>window.global = window;</script>` to index.html.
diff --git a/ui/yarn.lock b/ui/yarn.lock
index 6914a49..25677a2 100644
--- a/ui/yarn.lock
+++ b/ui/yarn.lock
@@ -3613,27 +3613,29 @@ mitt@^3.0.1:
   resolved "https://registry.yarnpkg.com/mitt/-/mitt-3.0.1.tgz#ea36cf0cc30403601ae074c8f77b7092cdab36d1"
   integrity sha512-vKivATfr97l2/QBCYAkXYDbrIWPM2IIKEl7YPhjCvKlG3kE2gm+uBo6nEXK3M5/Ffh/FLpKExzOQ3JJoJGFKBw==
 
-mobx-react-lite@^2.2.0:
-  version "2.2.2"
-  resolved "https://registry.yarnpkg.com/mobx-react-lite/-/mobx-react-lite-2.2.2.tgz#87c217dc72b4e47b22493daf155daf3759f868a6"
-  integrity sha512-2SlXALHIkyUPDsV4VTKVR9DW7K3Ksh1aaIv3NrNJygTbhXe2A9GrcKHZ2ovIiOp/BXilOcTYemfHHZubP431dg==
-
-mobx-react@^6.3.0:
-  version "6.3.1"
-  resolved "https://registry.yarnpkg.com/mobx-react/-/mobx-react-6.3.1.tgz#204f9756e42e19d91cb6598837063b7e7de87c52"
-  integrity sha512-IOxdJGnRSNSJrL2uGpWO5w9JH5q5HoxEqwOF4gye1gmZYdjoYkkMzSGMDnRCUpN/BNzZcFoMdHXrjvkwO7KgaQ==
+mobx-react-lite@^4.1.0:
+  version "4.1.0"
+  resolved "https://registry.yarnpkg.com/mobx-react-lite/-/mobx-react-lite-4.1.0.tgz#6a03ed2d94150848213cfebd7d172e123528a972"
+  integrity sha512-QEP10dpHHBeQNv1pks3WnHRCem2Zp636lq54M2nKO2Sarr13pL4u6diQXf65yzXUn0mkk18SyIDCm9UOJYTi1w==
   dependencies:
-    mobx-react-lite "^2.2.0"
+    use-sync-external-store "^1.4.0"
 
-mobx-utils@^5.6.1:
-  version "5.6.2"
-  resolved "https://registry.yarnpkg.com/mobx-utils/-/mobx-utils-5.6.2.tgz#4858acbdb03f0470e260854f87e8c2ba916ebaec"
-  integrity sha512-a/WlXyGkp6F12b01sTarENpxbmlRgPHFyR1Xv2bsSjQBm5dcOtd16ONb40/vOqck8L99NHpI+C9MXQ+SZ8f+yw==
+mobx-react@^9.2.0:
+  version "9.2.0"
+  resolved "https://registry.yarnpkg.com/mobx-react/-/mobx-react-9.2.0.tgz#c1e4d1ed406f6664d9de0787c948bac3a7ed5893"
+  integrity sha512-dkGWCx+S0/1mfiuFfHRH8D9cplmwhxOV5CkXMp38u6rQGG2Pv3FWYztS0M7ncR6TyPRQKaTG/pnitInoYE9Vrw==
+  dependencies:
+    mobx-react-lite "^4.1.0"
 
-mobx@^5.15.6:
-  version "5.15.7"
-  resolved "https://registry.yarnpkg.com/mobx/-/mobx-5.15.7.tgz#b9a5f2b6251f5d96980d13c78e9b5d8d4ce22665"
-  integrity sha512-wyM3FghTkhmC+hQjyPGGFdpehrcX1KOXsDuERhfK2YbJemkUhEB+6wzEN639T21onxlfYBmriA1PFnvxTUhcKw==
+mobx-utils@^6.1.1:
+  version "6.1.1"
+  resolved "https://registry.yarnpkg.com/mobx-utils/-/mobx-utils-6.1.1.tgz#61c66563e7646fb75462c189f4110a76d2e35768"
+  integrity sha512-ZR4tOKucWAHOdMjqElRl2BEvrzK7duuDdKmsbEbt2kzgVpuLuoYLiDCjc3QwWQl8CmOlxPgaZQpZ7emwNqPkIg==
+
+mobx@^6.13.7:
+  version "6.13.7"
+  resolved "https://registry.yarnpkg.com/mobx/-/mobx-6.13.7.tgz#70e5dda7a45da947f773b3cd3b065dfe7c8a75de"
+  integrity sha512-aChaVU/DO5aRPmk1GX8L+whocagUUpBQqoPtJk+cm7UOXUk87J4PeWCh6nNmTTIfEhiR9DI/+FnA8dln/hTK7g==
 
 ms@^2.1.3:
   version "2.1.3"
@@ -4543,6 +4545,11 @@ uri-js@^4.2.2:
   dependencies:
     punycode "^2.1.0"
 
+use-sync-external-store@^1.4.0:
+  version "1.5.0"
+  resolved "https://registry.yarnpkg.com/use-sync-external-store/-/use-sync-external-store-1.5.0.tgz#55122e2a3edd2a6c106174c27485e0fd59bcfca0"
+  integrity sha512-Rb46I4cGGVBmjamjphe8L/UnvJD+uPPtTkNvX5mZgqdbavhI4EbgIWJiIHXJ8bc/i9EQGPRh4DwEURJ552Do0A==
+
 vfile-message@^4.0.0:
   version "4.0.3"
   resolved "https://registry.yarnpkg.com/vfile-message/-/vfile-message-4.0.3.tgz#87b44dddd7b70f0641c2e3ed0864ba73e2ea8df4"