I have built my web scraping system ( https://awesomegoat.com ) on Ruby on Rails. And while I spent this Christmas-break exploring Elixir/Phoenix, I am so far staying with Ruby on Rails.
While it seems I could have built a slightly more (CPU & memory) efficient system in elixir, I am afraid the development of new features would be a bit slower and my time is more precious than the machine's.
Also, CPU & memory are likely not the constraints in the scraping exercise. What you will likely find later on that you will get blocked by Cloudflare on week 2 and superb backend won't make a difference.
While it seems I could have built a slightly more (CPU & memory) efficient system in elixir, I am afraid the development of new features would be a bit slower and my time is more precious than the machine's.
Also, CPU & memory are likely not the constraints in the scraping exercise. What you will likely find later on that you will get blocked by Cloudflare on week 2 and superb backend won't make a difference.