upstream auth {
    server auth:3000;
}

upstream users {
    server users:3001;
}

upstream products {
    server products:3002;
}

upstream orders {
    server orders:3003;
}

server {
    location /auth { proxy_pass http://auth; }
    location /users { proxy_pass http://users; }
    location /products { proxy_pass http://products; }
    location /orders { proxy_pass http://orders; }
}