Rounding in Go is hard to do correctly. That is, given a float64, truncate the fractional part (anything right of the decimal point), and add one to the truncated value if the fractional part was >= 0.5. This problem doesn’t come up often, but it does enough that as of this writing, the second hit on Google for golang round is a closed issue from the Go project, which declined to add a Round function to the math package.
Of course it did. Sigh.