Just after my application, I received an online technical test. The test is 3h long, under the surveillance of camera, without double screen, etc They required me to pass the test before the end of the week which and thus I had to cancel my plans for the weekend. This is not acceptable, requiring 3h of test from someone with such a short notice was a redflag. After ignoring this redflag, I've successfully passed the test (100/100 at the 3 exercices). I've then had a HR meeting. Two days after the HR meeting, they rejected my application without any explanations even after I politely asked them to do so. That's another red flag for you.