Julia is Eight times Slower than Go on Numerical Scheme

General Usage Performance
30

As for using structs: Just posted an implementation in some other context.

the same code as in the link above 
module Md2

Base.@kwdef mutable struct State
    b1::Bool = false
    b2::Bool = false
end

const st = State()
export st
end

using .Md2

julia> st.b1
false
julia> st.b1=true;
julia> st.b1
true

I my use case the performance was not relevant - but it is interesting to know how this way of encapsulation of variables into const objects compares with using Ref, array etc.