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diff --git a/packages/demobank-ui/src/hooks/index.ts b/packages/demobank-ui/src/hooks/index.ts
new file mode 100644
index 000000000..795df909d
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+++ b/packages/demobank-ui/src/hooks/index.ts
@@ -0,0 +1,151 @@
+/*
+ This file is part of GNU Taler
+ (C) 2021 Taler Systems S.A.
+
+ GNU Taler is free software; you can redistribute it and/or modify it under the
+ terms of the GNU General Public License as published by the Free Software
+ Foundation; either version 3, or (at your option) any later version.
+
+ GNU Taler is distributed in the hope that it will be useful, but WITHOUT ANY
+ WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
+ A PARTICULAR PURPOSE.  See the GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License along with
+ GNU Taler; see the file COPYING.  If not, see <http://www.gnu.org/licenses/>
+ */
+
+/**
+ *
+ * @author Sebastian Javier Marchano (sebasjm)
+ */
+
+import { StateUpdater, useState } from 'preact/hooks';
+export type ValueOrFunction<T> = T | ((p: T) => T);
+
+const calculateRootPath = () => {
+  const rootPath =
+    typeof window !== undefined
+      ? window.location.origin + window.location.pathname
+      : '/';
+  return rootPath;
+};
+
+export function useBackendURL(
+  url?: string,
+): [string, boolean, StateUpdater<string>, () => void] {
+  const [value, setter] = useNotNullLocalStorage(
+    'backend-url',
+    url || calculateRootPath(),
+  );
+  const [triedToLog, setTriedToLog] = useLocalStorage('tried-login');
+
+  const checkedSetter = (v: ValueOrFunction<string>) => {
+    setTriedToLog('yes');
+    return setter((p) => (v instanceof Function ? v(p) : v).replace(/\/$/, ''));
+  };
+
+  const resetBackend = () => {
+    setTriedToLog(undefined);
+  };
+  return [value, !!triedToLog, checkedSetter, resetBackend];
+}
+
+export function useBackendDefaultToken(): [
+  string | undefined,
+  StateUpdater<string | undefined>,
+  ] {
+  return useLocalStorage('backend-token');
+}
+
+export function useBackendInstanceToken(
+  id: string,
+): [string | undefined, StateUpdater<string | undefined>] {
+  const [token, setToken] = useLocalStorage(`backend-token-${id}`);
+  const [defaultToken, defaultSetToken] = useBackendDefaultToken();
+
+  // instance named 'default' use the default token
+  if (id === 'default')
+    return [defaultToken, defaultSetToken];
+
+  return [token, setToken];
+}
+
+export function useLang(initial?: string): [string, StateUpdater<string>] {
+  const browserLang =
+    typeof window !== 'undefined'
+      ? navigator.language || (navigator as any).userLanguage
+      : undefined;
+  const defaultLang = (browserLang || initial || 'en').substring(0, 2);
+  const [value, setValue] = useNotNullLocalStorage('lang-preference', defaultLang);
+  function updateValue(newValue: (string | ((v: string) => string))) {
+    if (document.body.parentElement) {
+      const htmlElement = document.body.parentElement
+      if (typeof newValue === 'string') {
+        htmlElement.lang = newValue;
+        setValue(newValue)
+      } else if (typeof newValue === 'function')
+        setValue((old) => {
+          const nv = newValue(old)
+          htmlElement.lang = nv;
+          return nv
+        })
+    } else setValue(newValue)
+  }
+  return [value, updateValue]
+}
+
+export function useLocalStorage(
+  key: string,
+  initialValue?: string,
+): [string | undefined, StateUpdater<string | undefined>] {
+  const [storedValue, setStoredValue] = useState<string | undefined>(():
+    | string
+    | undefined => {
+    return typeof window !== 'undefined'
+      ? window.localStorage.getItem(key) || initialValue
+      : initialValue;
+  });
+
+  const setValue = (
+    value?: string | ((val?: string) => string | undefined),
+  ) => {
+    setStoredValue((p) => {
+      const toStore = value instanceof Function ? value(p) : value;
+      if (typeof window !== 'undefined')
+        if (!toStore)
+          window.localStorage.removeItem(key);
+        else
+          window.localStorage.setItem(key, toStore);
+
+
+      return toStore;
+    });
+  };
+
+  return [storedValue, setValue];
+}
+
+export function useNotNullLocalStorage(
+  key: string,
+  initialValue: string,
+): [string, StateUpdater<string>] {
+  const [storedValue, setStoredValue] = useState<string>((): string => {
+    return typeof window !== 'undefined'
+      ? window.localStorage.getItem(key) || initialValue
+      : initialValue;
+  });
+
+  const setValue = (value: string | ((val: string) => string)) => {
+    const valueToStore = value instanceof Function ? value(storedValue) : value;
+    setStoredValue(valueToStore);
+    if (typeof window !== 'undefined')
+      if (!valueToStore)
+        window.localStorage.removeItem(key);
+      else
+        window.localStorage.setItem(key, valueToStore);
+
+
+  };
+
+  return [storedValue, setValue];
+}