I don't know. k8s is pretty complicated. How many small/medium apps need more than this nginx/Terraform/Docker example? This would be a lot more difficult to set up in k8s (pods, ingress, etc.)

Terraform:

resource "docker_container" "app" { count = 2

  name  = "app-${count.index}"
  hostname = "app-${count.index}"
  image = "app:${var.app_version}"
  restart = "always"

  env = [
    ...
  ]

  ports {
    internal = parseint("${var.app_port}", 10) + count.index
    external = parseint("${var.app_port}", 10) + count.index
  }

  networks_advanced {
    name = "${docker_network.private_network.name}"
    aliases = ["app-${count.index}"]
  }

  depends_on = [
    ...
  ]

Nginx:

http { ...

  upstream app {
    server app-0:3000;
    server app-1:3001;
  }

  server {
    listen 80;

    root /usr/share/nginx/html;

    location ~* ^/api/ {
      rewrite ^/api/(.*) /$1 break;
      proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
      proxy_set_header Host $host;
      proxy_http_version 1.1;
      proxy_pass http://app;
    }
  }
}