Dagger is a frustrating time sink – it's interesting for what should be boring infrastructure. I've wasted too many hours debugging low-level details of buildkit and dealing with leaky kernel abstractions instead of building actual products.
Nix, Bazel, and similar alternatives may have learning curves, but they provide clearer guardrails and more predictable outcomes without exposing so many implementation details. I deeply regret the time I spent working with Dagger.