It takes a bit of work to get around the mutable buffers problem in D language arrays. I found it made a performance difference in xml parsing.
https://github.com/betrixed/dlang-xml/blob/master/xml/util/buffer.d /** Buffer(T) - Versatile appendable D array for buffer reuse, append, reset with preserved capacity. Has additional template specializations for char, wchar, dchar, which always has an extra space for appending a terminating null character. Magic property is no memory reallocation or capacity loss if length set to zero. Resulting speed ups from reduced memory manager work. Perhaps reduction in hardware cache misses. Almost a drop in replacement for T[]. Some features adopted from std.array and std.range */ -- Technosphere-brain-shrink - trying to give it up