You need to use PyPy to run this. To get started, using a recent virtualenv (1.6.1 or newer), virtualenvwrapper, and a recent PyPy (1.5 or trunk). On Mac OSX you will also need to install binutils, to make objdump available. To create a virtualenv: mkvirtualenv --python=/path/to/pypy pypy-viewer Now install the dependencies: pip install flask pygments simplejson or python setup.py develop It also requires pypy to be importable (as in source code), you can do this by setting your ``PYTHONPATH`` enviromental variable. Finally, run it: jitviewer.py log.pypylog where log.pypylog is a logfile generated by PYPYLOG=jit-log-opt,jit-backend:log.pypylog pypy <args>. An example log file comes with a checkout.