Process unnecessarily long (3 months and half) and not constructive at all. After the first home assessment, the logical and aptitude tests, it started the interviews, in which for 4/5 times I've been repeating always the same stuff, with different persons. The 6th (and the last) interview has been the technical one in the area I was interested in, with 5 questions over coding. After "only" 3 weeks it comes the feedback: rejected, but apparently the motivation is inconsistent with the evidence.
After all this, doubts remain, since noticing the continuous spam of "new" opportunities at Canonical and the discrete amount on negative reviews here, one could easily draws its own conclusions.