let f request =
<%s! Dream.form_tag ~action:"/register" request %>
  <div class="mb-3">
    <label for="nick" class="form-label">Nick</label>
    <input name="nick" type="text" class="form-control" id="nick">
  </div>
  <div class="mb-3">
    <label for="email" class="form-label">Email address</label>
    <input name="email" type="email" class="form-control" id="email">
  </div>
  <div class="mb-3">
    <label for="password" class="form-label">Password</label>
    <input name="password" type="password" class="form-control" id="password">
  </div>
  <button type="submit" class="btn btn-primary">Submit</button>
</form>