The contexttest repository now contains a Makefile to use for checking one context tree against another. There's a README alongside it but here's the quickstart svn export . /tmp/testdir cd /tmp/testdir make -k A=20070112 B=20070123 >& world.log (the -k is so it doesn't stop on the first error) It will 1. (if not already done) Download ConTeXt versions 2007.01.12 and 2007.01.23 from the museum, put each in its own subtree, make formats for each 2. Do the following for each test-NNN.tex file: a. Run it through 2007.01.12 to make test-NNN-20070112.pdf b. Run it through 2007.01.23 to make test-NNN-20070123.pdf c. Feed those pdfs to utils/compare-pdfs.sh to generate a bitmap diff d. Report differences found by compare-pdfs.sh (dB on each page) It was interesting running it. I haven't sorted through all the output yet, but a one point was that a few unicode fonts are a problem (maybe because I don't have them, but it makes texexec loop for a long time doing mktextfm and the like). More details to follow. Notes: If you want to view the image diffs as they are generated, set the viewer shell variable in compare-pdfs.sh (I often use xloadimage). I'd be very surprised if the Makefile worked on anything but Linux (uses features of bash + GNU make). I was pretty careful about re-entrancy, so the following works fine at least in my testing: make -k -j 4 A=20070112 B=20070123 -Sanjoy `A nation of slaves is always prepared to applaud the clemency of their master who, in the abuse of absolute power, does not proceed to the last extremes of injustice and oppression.' (Gibbon)