Set diffrent outgoing proxy in docker-compose file

I want to set a different outgoing proxy for zulip. How to do it properly? Zulip docs for non docker install: To use a custom outgoing proxy: 1. Add the following block to /etc/zulip/zulip.conf, substituting in your proxy’s hostname/IP and port: [http_proxy] host = 127.0.0.1 port = 4750 I tried with no luck in my docker-compose.yml: PROXY_HOST: "172.16.0.2" PROXY_PORT: "8081" Is it possible to support this in your entrypoint.sh?