Is there any advantage whatsoever to this, as opposed to a proper monad? I’m not seeing it.

The point of monads is that they solve this exact category of problem in the simplest possible way.

One more practical point is that a full monad doesn’t fit very naturally into a pipe-first interface.

Once you commit to a real monad, you need map/flatMap, lifting, unwrapping, and rules about staying inside the context across the whole pipeline. At that point, the pipe abstraction stops being the primary mental model — the monad does.

SideEffect deliberately avoids that. It keeps the pipe interface intact and only adds a single, explicit signal: “stop here”. That’s why it’s less powerful than a monad, but also much simpler to integrate into existing pipe-based code.

fp-pack is also intentionally scoped for everyday frontend developers.

It tries to borrow function composition and declarative structure without requiring familiarity with full FP abstractions like monads or effect systems.