Wow, for screenshots much faster than chromium:

  $ time target/release/fetch_and_render "https://www.lauf-goethe-lauf.de/"
  real 0m0,685s
  user 0m0,548s
  sys 0m0,070s
  
  $ time chromium --headless --disable-gpu --screenshot=out.png --window-size=1200,800 https://www.lauf-goethe-lauf.de/
  real 0m1,099s
  user 0m0,927s
  sys 0m0,692s

# edit: with a hot-standby chrome and a running node instance a can reach 0,369s seconds here