diff --git a/.dockerignore b/.dockerignore
index 7f5bf79b..130e3269 100644
--- a/.dockerignore
+++ b/.dockerignore
@@ -11,7 +11,7 @@ server/test
 server/.tmp
 server/.venv
 
-server/views/index.html
+server/views/index.ejs
 
 server/data/*
 !server/data/.gitkeep
diff --git a/.github/workflows/build-and-publish-release-package.yml b/.github/workflows/build-and-publish-release-package.yml
index 3b9d8970..f53e7ac5 100644
--- a/.github/workflows/build-and-publish-release-package.yml
+++ b/.github/workflows/build-and-publish-release-package.yml
@@ -34,7 +34,7 @@ jobs:
         working-directory: ./client
 
       - name: Build client
-        run: DISABLE_ESLINT_PLUGIN=true npm run build
+        run: INDEX_FORMAT=ejs DISABLE_ESLINT_PLUGIN=true npm run build
         working-directory: ./client
 
       - name: Include licenses into dist
@@ -45,7 +45,7 @@ jobs:
       - name: Include built client into dist
         run: |
           mv ../../client/dist/* public
-          cp public/index.html views
+          mv public/index.ejs views
         working-directory: ./server/dist
 
       - name: Create release package
diff --git a/.github/workflows/build-and-push-docker-image.yml b/.github/workflows/build-and-push-docker-image.yml
index e01ab2b4..45112b37 100644
--- a/.github/workflows/build-and-push-docker-image.yml
+++ b/.github/workflows/build-and-push-docker-image.yml
@@ -24,13 +24,13 @@ jobs:
 
       - name: Build client
         run: |
-          DISABLE_ESLINT_PLUGIN=true npm run build
+          INDEX_FORMAT=ejs DISABLE_ESLINT_PLUGIN=true npm run build
           mv dist build
         working-directory: ./client
 
       - name: Update Dockerfile to use prebuilt client
         run: |
-          sed -i '/^FROM node:22 AS client/,/^  && DISABLE_ESLINT_PLUGIN=true npm run build$/c\
+          sed -i '/^FROM node:22 AS client/,/^  && INDEX_FORMAT=ejs DISABLE_ESLINT_PLUGIN=true npm run build$/c\
           FROM node:22 AS client\n\
           WORKDIR /app\n\
           COPY client/build /app/dist' Dockerfile
diff --git a/.github/workflows/build-and-push-docker-nightly-image.yml b/.github/workflows/build-and-push-docker-nightly-image.yml
index 33305e1f..7858372f 100644
--- a/.github/workflows/build-and-push-docker-nightly-image.yml
+++ b/.github/workflows/build-and-push-docker-nightly-image.yml
@@ -38,13 +38,13 @@ jobs:
 
       - name: Build client
         run: |
-          DISABLE_ESLINT_PLUGIN=true npm run build
+          INDEX_FORMAT=ejs DISABLE_ESLINT_PLUGIN=true npm run build
           mv dist build
         working-directory: ./client
 
       - name: Update Dockerfile to use prebuilt client
         run: |
-          sed -i '/^FROM node:22 AS client/,/^  && DISABLE_ESLINT_PLUGIN=true npm run build$/c\
+          sed -i '/^FROM node:22 AS client/,/^  && INDEX_FORMAT=ejs DISABLE_ESLINT_PLUGIN=true npm run build$/c\
           FROM node:22 AS client\n\
           WORKDIR /app\n\
           COPY client/build /app/dist' Dockerfile
diff --git a/.github/workflows/build-and-test.yml b/.github/workflows/build-and-test.yml
index 58ba33ad..d16f51c9 100644
--- a/.github/workflows/build-and-test.yml
+++ b/.github/workflows/build-and-test.yml
@@ -46,7 +46,7 @@ jobs:
         run: |
           npm install
           cd client
-          npm run build
+          INDEX_FORMAT=ejs npm run build
 
       - name: Set up and start server for testing
         env:
diff --git a/Dockerfile b/Dockerfile
index 575fa822..dc8d1338 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -22,7 +22,7 @@ COPY client .
 
 RUN npm install npm --global \
   && npm install --omit=dev \
-  && DISABLE_ESLINT_PLUGIN=true npm run build
+  && INDEX_FORMAT=ejs DISABLE_ESLINT_PLUGIN=true npm run build
 
 # Stage 3: Final image
 FROM node:22-alpine
@@ -41,12 +41,12 @@ COPY --from=server --chown=node:node /app/node_modules node_modules
 COPY --from=server --chown=node:node /app/dist .
 
 COPY --from=client --chown=node:node /app/dist public
-COPY --from=client --chown=node:node /app/dist/index.html views
 
 RUN python3 -m venv .venv \
   && .venv/bin/pip3 install --upgrade pip \
   && .venv/bin/pip3 install -r requirements.txt --no-cache-dir \
   && mv .env.sample .env \
+  && mv public/index.ejs views \
   && npm config set update-notifier false
 
 VOLUME /app/data
diff --git a/client/src/api/http.js b/client/src/api/http.js
index 4d5ceca1..f48d03a0 100755
--- a/client/src/api/http.js
+++ b/client/src/api/http.js
@@ -18,7 +18,7 @@ const http = {};
         return result;
       }, new FormData());
 
-    return fetch(`${Config.SERVER_BASE_URL}/api${url}`, {
+    return fetch(`${Config.BASE_PATH}/api${url}`, {
       method,
       headers,
       body: formData,
diff --git a/client/src/api/socket.js b/client/src/api/socket.js
index 81b9ccd8..4a962d5b 100755
--- a/client/src/api/socket.js
+++ b/client/src/api/socket.js
@@ -10,7 +10,7 @@ import Config from '../constants/Config';
 
 const io = sailsIOClient(socketIOClient);
 
-io.sails.url = Config.SERVER_BASE_URL;
+io.sails.path = `${Config.BASE_PATH}/socket.io`;
 io.sails.autoConnect = false;
 io.sails.reconnection = true;
 io.sails.useCORSRouteToGetCookie = false;
diff --git a/client/src/components/common/Linkify/Link.jsx b/client/src/components/common/Linkify/Link.jsx
index ff1d15c5..80122b73 100644
--- a/client/src/components/common/Linkify/Link.jsx
+++ b/client/src/components/common/Linkify/Link.jsx
@@ -10,6 +10,7 @@ import { useSelector } from 'react-redux';
 import history from '../../../history';
 import selectors from '../../../selectors';
 import matchPaths from '../../../utils/match-paths';
+import Config from '../../../constants/Config';
 import Paths from '../../../constants/Paths';
 
 const Link = React.memo(({ href, content, stopPropagation, ...props }) => {
@@ -23,7 +24,8 @@ const Link = React.memo(({ href, content, stopPropagation, ...props }) => {
     }
   }, [href]);
 
-  const isSameSite = !!url && url.origin === window.location.origin;
+  const isSameSite =
+    !!url && url.origin === window.location.origin && url.pathname.startsWith(Config.BASE_PATH);
 
   const cardsPathMatch = useMemo(() => {
     if (!isSameSite) {
diff --git a/client/src/configs/markdown-plugins/link.js b/client/src/configs/markdown-plugins/link.js
index 09f03fa6..b0463a9a 100644
--- a/client/src/configs/markdown-plugins/link.js
+++ b/client/src/configs/markdown-plugins/link.js
@@ -4,6 +4,7 @@
  */
 
 import history from '../../history';
+import Config from '../../constants/Config';
 
 const SAME_SITE_CLASS = 'same-site';
 
@@ -30,7 +31,9 @@ function process(token, nextToken) {
     return;
   }
 
-  const isSameSite = url.origin === window.location.origin;
+  const isSameSite =
+    url.origin === window.location.origin && url.pathname.startsWith(Config.BASE_PATH);
+
   const trimOrigin = isSameSite && nextToken.type === 'text' && nextToken.content === href;
 
   if (isSameSite) {
diff --git a/client/src/constants/Config.js b/client/src/constants/Config.js
index e48c58ab..029e75ee 100755
--- a/client/src/constants/Config.js
+++ b/client/src/constants/Config.js
@@ -3,8 +3,7 @@
  * Licensed under the Fair Use License: https://github.com/plankanban/planka/blob/master/LICENSE.md
  */
 
-const SERVER_BASE_URL =
-  import.meta.env.VITE_SERVER_BASE_URL || (import.meta.env.DEV ? 'http://localhost:1337' : '');
+const BASE_PATH = window.BASE_PATH || '';
 
 const ACCESS_TOKEN_KEY = 'accessToken';
 const ACCESS_TOKEN_VERSION_KEY = 'accessTokenVersion';
@@ -20,7 +19,7 @@ const MAX_SIZE_TO_DISPLAY_CONTENT = 256 * 1024;
 const IS_MAC = navigator.platform.startsWith('Mac');
 
 export default {
-  SERVER_BASE_URL,
+  BASE_PATH,
   ACCESS_TOKEN_KEY,
   ACCESS_TOKEN_VERSION_KEY,
   ACCESS_TOKEN_VERSION,
diff --git a/client/src/constants/Paths.js b/client/src/constants/Paths.js
index 91bd78d0..940eb932 100755
--- a/client/src/constants/Paths.js
+++ b/client/src/constants/Paths.js
@@ -3,12 +3,14 @@
  * Licensed under the Fair Use License: https://github.com/plankanban/planka/blob/master/LICENSE.md
  */
 
-const ROOT = '/';
-const LOGIN = '/login';
-const OIDC_CALLBACK = '/oidc-callback';
-const PROJECTS = '/projects/:id';
-const BOARDS = '/boards/:id';
-const CARDS = '/cards/:id';
+import Config from './Config';
+
+const ROOT = `${Config.BASE_PATH}/`;
+const LOGIN = `${Config.BASE_PATH}/login`;
+const OIDC_CALLBACK = `${Config.BASE_PATH}/oidc-callback`;
+const PROJECTS = `${Config.BASE_PATH}/projects/:id`;
+const BOARDS = `${Config.BASE_PATH}/boards/:id`;
+const CARDS = `${Config.BASE_PATH}/cards/:id`;
 
 export default {
   ROOT,
diff --git a/client/src/utils/access-token-storage.js b/client/src/utils/access-token-storage.js
index e07924f4..0ed81641 100755
--- a/client/src/utils/access-token-storage.js
+++ b/client/src/utils/access-token-storage.js
@@ -8,24 +8,28 @@ import { jwtDecode } from 'jwt-decode';
 
 import Config from '../constants/Config';
 
+const PATH = Config.BASE_PATH || '/';
+
 export const setAccessToken = (accessToken) => {
   const { exp } = jwtDecode(accessToken);
   const expires = new Date(exp * 1000);
 
   Cookies.set(Config.ACCESS_TOKEN_KEY, accessToken, {
     expires,
+    path: PATH,
     secure: window.location.protocol === 'https:',
     sameSite: 'strict',
   });
 
   Cookies.set(Config.ACCESS_TOKEN_VERSION_KEY, Config.ACCESS_TOKEN_VERSION, {
     expires,
+    path: PATH,
   });
 };
 
 export const removeAccessToken = () => {
-  Cookies.remove(Config.ACCESS_TOKEN_KEY);
-  Cookies.remove(Config.ACCESS_TOKEN_VERSION_KEY);
+  Cookies.remove(Config.ACCESS_TOKEN_KEY, { path: PATH });
+  Cookies.remove(Config.ACCESS_TOKEN_VERSION_KEY, { path: PATH });
 };
 
 export const getAccessToken = () => {
diff --git a/client/tests/setup-symlinks.sh b/client/tests/setup-symlinks.sh
index f7f57f70..2b068b2b 100755
--- a/client/tests/setup-symlinks.sh
+++ b/client/tests/setup-symlinks.sh
@@ -17,6 +17,6 @@ ln -s ${CLIENT_PATH}/logo512.png ${SERVER_PUBLIC_PATH}/logo512.png && echo "Link
 ln -s ${CLIENT_PATH}/manifest.json ${SERVER_PUBLIC_PATH}/manifest.json && echo "Linked manifest.json successfully"
 ln -s ${CLIENT_PATH}/robots.txt ${SERVER_PUBLIC_PATH}/robots.txt && echo "Linked robots.txt successfully"
 ln -s ${CLIENT_PATH}/assets ${SERVER_PUBLIC_PATH}/assets && echo "Linked assets folder successfully"
-ln -s ${CLIENT_PATH}/index.html ${SERVER_VIEWS_PATH}/index.html && echo "Linked index.html successfully"
+ln -s ${CLIENT_PATH}/index.ejs ${SERVER_VIEWS_PATH}/index.ejs && echo "Linked index.ejs successfully"
 
 echo "Setup symbolic links completed successfully."
diff --git a/client/vite.config.js b/client/vite.config.js
index 231cd045..60245fa3 100644
--- a/client/vite.config.js
+++ b/client/vite.config.js
@@ -1,13 +1,42 @@
+import fs from 'fs';
+import path from 'path';
+import { fileURLToPath } from 'url';
 import { defineConfig } from 'vite';
 import commonjs from 'vite-plugin-commonjs';
 import { nodePolyfills } from 'vite-plugin-node-polyfills';
+// eslint-disable-next-line import/no-unresolved
 import react from '@vitejs/plugin-react';
 import svgr from 'vite-plugin-svgr';
 // eslint-disable-next-line import/no-unresolved
 import browserslistToEsbuild from 'browserslist-to-esbuild';
 
+// eslint-disable-next-line no-underscore-dangle
+const __dirname = path.dirname(fileURLToPath(import.meta.url));
+
+const createEjsTemplate = () => ({
+  name: 'create-ejs-template',
+  closeBundle() {
+    if (process.env.INDEX_FORMAT !== 'ejs') return;
+
+    const distPath = path.resolve(__dirname, 'dist');
+    const htmlPath = path.join(distPath, 'index.html');
+
+    if (!fs.existsSync(htmlPath)) return;
+
+    const html = fs.readFileSync(htmlPath, 'utf8');
+
+    const ejs = html
+      .replace(/(href|src)="\.\/([^"]+)"/g, '$1="<%- basePath %>/$2"')
+      .replace('</head>', "  <script>window.BASE_PATH = '<%- basePath %>';</script>\n  </head>");
+
+    fs.writeFileSync(path.join(distPath, 'index.ejs'), ejs);
+    fs.unlinkSync(htmlPath);
+  },
+});
+
 // https://vitejs.dev/config/
 export default defineConfig({
+  base: './',
   plugins: [
     commonjs(),
     nodePolyfills({
@@ -15,6 +44,7 @@ export default defineConfig({
     }),
     react(),
     svgr(),
+    createEjsTemplate(),
   ],
   resolve: {
     alias: {
@@ -24,6 +54,10 @@ export default defineConfig({
   server: {
     port: 3000,
     open: true,
+    proxy: {
+      '/api': 'http://localhost:1337',
+      '/socket.io': { target: 'http://localhost:1337', ws: true },
+    },
   },
   build: {
     target: browserslistToEsbuild(['>0.2%', 'not dead', 'not op_mini all']),
diff --git a/server/.buildignore b/server/.buildignore
index 9f527b0b..43a420a5 100644
--- a/server/.buildignore
+++ b/server/.buildignore
@@ -20,7 +20,7 @@ test
 .tmp
 .venv
 
-views/index.html
+views/index.ejs
 
 data/*
 
diff --git a/server/.gitignore b/server/.gitignore
index 1ff70729..bb317dac 100644
--- a/server/.gitignore
+++ b/server/.gitignore
@@ -134,7 +134,7 @@ swagger.json
 dist
 logs
 
-views/index.html
+views/index.ejs
 
 data/*
 !data/.gitkeep
diff --git a/server/api/controllers/index.js b/server/api/controllers/index.js
new file mode 100644
index 00000000..57b636f6
--- /dev/null
+++ b/server/api/controllers/index.js
@@ -0,0 +1,19 @@
+/*!
+ * Copyright (c) 2025 PLANKA Software GmbH
+ * Licensed under the Fair Use License: https://github.com/plankanban/planka/blob/master/LICENSE.md
+ */
+
+module.exports = {
+  exits: {
+    success: {
+      responseType: 'view',
+      viewTemplatePath: 'index',
+    },
+  },
+
+  fn() {
+    return {
+      basePath: sails.config.custom.baseUrlPath,
+    };
+  },
+};
diff --git a/server/api/helpers/utils/clear-http-only-token-cookie.js b/server/api/helpers/utils/clear-http-only-token-cookie.js
index bcd7de35..c95ec98b 100644
--- a/server/api/helpers/utils/clear-http-only-token-cookie.js
+++ b/server/api/helpers/utils/clear-http-only-token-cookie.js
@@ -15,7 +15,7 @@ module.exports = {
 
   fn(inputs) {
     inputs.response.clearCookie('httpOnlyToken', {
-      path: sails.config.custom.baseUrlPath,
+      path: sails.config.custom.baseUrlPath || '/',
     });
   },
 };
diff --git a/server/api/helpers/utils/set-http-only-token-cookie.js b/server/api/helpers/utils/set-http-only-token-cookie.js
index 71867ce0..b13a648e 100644
--- a/server/api/helpers/utils/set-http-only-token-cookie.js
+++ b/server/api/helpers/utils/set-http-only-token-cookie.js
@@ -24,7 +24,7 @@ module.exports = {
   fn(inputs) {
     inputs.response.cookie('httpOnlyToken', inputs.value, {
       expires: new Date(inputs.accessTokenPayload.exp * 1000),
-      path: sails.config.custom.baseUrlPath,
+      path: sails.config.custom.baseUrlPath || '/',
       secure: sails.config.custom.baseUrlSecure,
       httpOnly: true,
       sameSite: 'strict',
diff --git a/server/config/custom.js b/server/config/custom.js
index 5378e407..5db04627 100644
--- a/server/config/custom.js
+++ b/server/config/custom.js
@@ -41,7 +41,7 @@ module.exports.custom = {
   version,
 
   baseUrl,
-  baseUrlPath: parsedBasedUrl.pathname,
+  baseUrlPath: parsedBasedUrl.pathname.replace(/\/$/, ''), // Remove trailing slash
   baseUrlSecure: parsedBasedUrl.protocol === 'https:',
 
   maxUploadFileSize: envToBytes(process.env.MAX_UPLOAD_FILE_SIZE),
diff --git a/server/config/policies.js b/server/config/policies.js
index 9c62dd20..b2a64c3b 100644
--- a/server/config/policies.js
+++ b/server/config/policies.js
@@ -44,6 +44,7 @@ module.exports.policies = {
 
   '_internal/update-config': ['is-authenticated', 'is-internal'],
 
+  index: true,
   'swagger/show': true,
   'bootstrap/show': true,
   'terms/show': true,
diff --git a/server/config/routes.js b/server/config/routes.js
index 38cc16aa..4f5519cf 100644
--- a/server/config/routes.js
+++ b/server/config/routes.js
@@ -266,7 +266,7 @@ module.exports.routes = {
   },
 
   'GET /*': {
-    view: 'index',
+    action: 'index',
     skipAssets: true,
   },
 };
diff --git a/server/config/views.js b/server/config/views.js
index 55ec7950..c9889c6b 100644
--- a/server/config/views.js
+++ b/server/config/views.js
@@ -24,7 +24,7 @@ module.exports.views = {
    *
    */
 
-  extension: 'html',
+  // extension: 'ejs',
 
   /**
    *