by default Julia uses locking for writes to guarantee thread safety when multiple writes are happening. That said, it's totally possible to go way faster using buffered IO.
```
for i = 1:typemax(UInt64)
s = ""
if i % 3 == 0
s = s * "fizz"
end
if i % 5 == 0
s = s * "buzz"
end
if s == ""
s = string(i)
end
println(s)
end
```
Measured over 10 s after a 10 s burn-in period, Julia 1.7 on Ubuntu 21.10.