To be fair, there are lots of tricks to get stuff moving faster in Python, usually by invoking some module that delegates to native code. This was, IIRC, doing everything in the most straightforward way. But I did port the source code essentially line-by-line and this was within the first week of using Crystal. Any grave (i. e. measurable in O-notation) errors would have just carried over, and no sophistication was involved in my Crystal code.