Match Against Doctrine Extension configuration

I'm trying to make match against doctrine extension work but i get error with doctrine configuration file. I got Unrecognized option "dql" under "doctrine.orm" . How to propely use symfony 4 + doctrine + match against extension?

Match against file + conf https://gist.github.com/ZeBigDuck/1234419#file-addfulltextindexescommand-php

parameters:
    # Adds a fallback DATABASE_URL if the env var is not set.
    # This allows you to run cache:warmup even if your
    # environment variables are not available yet.
    # You should not need to change this value.
    env(DATABASE_URL): ''

doctrine:
    dbal:
        # configure these for your database server
        driver: 'pdo_mysql'
        server_version: '5.7'
        charset: utf8mb4
        default_table_options:
            charset: utf8mb4
            collate: utf8mb4_unicode_ci

        url: '%env(resolve:DATABASE_URL)%'
    orm:
      dql:
        auto_generate_proxy_classes: '%kernel.debug%'
        naming_strategy: doctrine.orm.naming_strategy.underscore
        auto_mapping: true
#        string_functions:
#          MATCH_AGAINST: App\Extension\Doctrine\MatchAgainst
        mappings:
            App:
                is_bundle: false
                type: annotation
                dir: '%kernel.project_dir%/src/Entity'
                prefix: 'App\Entity'
                alias: App
      entity_managers:
        default:
          dql:
            string_functions:
              MATCH_AGAINST: App\Extension\Doctrine\MatchAgainst

Try it like this:

    orm:
       auto_generate_proxy_classes: '%kernel.debug%'
       naming_strategy: doctrine.orm.naming_strategy.underscore
       auto_mapping: true
       dql:
         string_functions:
            MATCH_AGAINST: App\Extension\Doctrine\MatchAgainst

EDIT.. It should be something like this (not tested):

doctrine:
    dbal:
      # configure these for your database server
      driver: 'pdo_mysql'
      server_version: '5.7'
      charset: utf8mb4
      default_table_options:
        charset: utf8mb4
        collate: utf8mb4_unicode_ci

      url: '%env(resolve:DATABASE_URL)%'
    orm:
      auto_generate_proxy_classes: '%kernel.debug%'
      naming_strategy: doctrine.orm.naming_strategy.underscore
      auto_mapping: true
      dql:
        string_functions:
          MATCH_AGAINST: App\Extension\Doctrine\MatchAgainst
      mappings:
        App:
          is_bundle: false
          type: annotation
          dir: '%kernel.project_dir%/src/Entity'
          prefix: 'App\Entity'
          alias: App