Value Object and Primitive Obsession code-smell

LOL, uh sorry miscommunication on my part (and sorta misdirected squarely at you). Of course “changes” include validations (hence “hand-in-hand”). The params-manipulation thing is just a huge pet peeve of mine and I always assumed that it stems from people thinking changesets is only about validations. Ok, no need to talk about Ecto any further.