Hi folks, Yesterday, I was able to make my simple cross-correlation script to work with PyPy / NumPy at all with the valuable help of bdk, however, I ended up being quite disappointed about the performance. I stripped out everything I could and ended up with something like this: Python 3: $ time python corrbench.py 0 1 2 real 0m2.225s user 0m1.980s sys 0m0.240s PyPy from hg / NumPy from hg (3581f7a906c9+): $ time python corrbench.py 0 1 2 real 1m2.928s user 1m2.460s sys 0m0.270s What this script does, it basically generates two time series of ~5 000 elements and bins them into 3 000 000 buckets, which it then multiples element-wise and sums up the result. I expected a huge performance boost, of course :-) I think I'll be running this with plain Python for now, but I hope that's a valuable benchmark for you guys! -- Sincerely yours, Yury V. Zaytsev