It is just wishful thinking that your electrician did not made a single mistake. Assume he did. Then what? You will burn to death at one random night?

Aluminum also expands and contracts much more than copper when it gets hot, so it can just wiggle its way out of any connection. Furthermore aluminum is soft, and if you bend it too much, it will crack or break, so not only connection can get problematic, any corners can get easily problematic as well.

Only madman would get his house installed with aluminum wiring.