function compute(t::AbstractTask; data...)
    return error("Need to implement compute()")
end

function compute_effort(t::AbstractTask)
    # default implementation using compute
    return error("Need to implement compute_effort()")
end

function data(t::AbstractTask)
    return error("Need to implement data()")
end

compute_effort(t::AbstractDataTask) = 0
compute(t::AbstractDataTask; data...) = data
data(t::AbstractDataTask) = getfield(t, :data)

data(t::AbstractComputeTask) = 0

function compute_effort(t::FusedComputeTask)
    (T1, T2) = collect(typeof(t).parameters)
    return compute_effort(T1()) + compute_effort(T2())
end

# actual compute functions for the tasks can stay undefined for now
# compute(t::ComputeTaskU, data::Any) = mycomputation(data)

function compute_intensity(t::AbstractTask)::UInt64
    if data(t) == 0
        return typemax(UInt64)
    end
    return compute_effort(t) / data(t)
end