Why not install php extension redis?

Question

Docker

trying to put connect radish container here is compose

php-fpm:
    build: docker/php-fpm
    depends_on:
      - db
      - redis
    links:
      - redis
      - db
    volumes:
      - "./:/www"
    environment:
      - DOCKER_PHP_CONFIG=${DOCKER_PHP_CONFIG}
      - DOCKER_XDEBUG=${DOCKER_XDEBUG}
      - DOCKER_SUPERVISOR=${DOCKER_SUPERVISOR}
      - DOCKER_CRON=${DOCKER_CRON}
    networks:
        - laravel
      php-fpm:
    build: docker/php-fpm
    depends_on:
      - db
      - redis
    links:
      - redis
      - db
    volumes:
      - "./:/www"
    environment:
      - DOCKER_PHP_CONFIG=${DOCKER_PHP_CONFIG}
      - DOCKER_XDEBUG=${DOCKER_XDEBUG}
      - DOCKER_SUPERVISOR=${DOCKER_SUPERVISOR}
      - DOCKER_CRON=${DOCKER_CRON}
    networks:
        - laravel

like this in php-fpm dockerfile

RUN pecl install redis-5.3.1 \
 && docker-php-ext-enable redis

this is the answer i get

Starting to download redis-5.3.1.tgz (264,485 bytes)
......................................................done: 264,485 bytes
29 source files, building
running: phpize
Configuring for:
PHP Api Version:         20170718
Zend Module Api No:      20170718
Zend Extension Api No:   320170718
Cannot find autoconf. Please check your autoconf installation and the
$PHP_AUTOCONF environment variable. Then, rerun this script.
ERROR: `phpize' failed
ERROR: Service 'php-fpm' failed to build: The command '/bin/sh -c pecl install redis-5.3.1  && docker-php-ext-enable redis' returned a non-zero code: 1

what is not so?