Xiao Jia

The best way to contact me is via email .

You can also find me on DBLP, GitHub, LinkedIn, StackOverflow, and Twitter.

What might be useful but I don't have time to do

Monitor keystrokes in Vim and educate me with better alternative keystrokes

Coq Resources

Software Foundations

Certified Programming with Dependent Types

Coqoon (Eclipse plugin)






Remove delay in SSH login
UseDNS no                     # Add to /etc/ssh/sshd_config
options single-request-reopen # Add to /etc/resolv.conf
Remove watermarks (e.g. DRAFT) in PDF files
pdftk draft.pdf output uncompressed.pdf uncompress
less uncompressed.pdf          # check general structure
grep -a DRAFT uncompressed.pdf # check specific lines
cat uncompressed.pdf | sed 's/DRAFT//g' > without-draft.pdf
pdfjam examples
pdfjam ch1.pdf --landscape --nup 2x1 --a4paper --outfile ch1-2x1.pdf
pdf2ps ch1-2x1.pdf ch1-2x1.ps
pdfjam all.pdf --trim '2cm 3cm 2.5cm 1.5cm' --clip true --outfile /dev/stdout |\
  pdfjam --frame true --nup '2x2' --a4paper --outfile all-2x2-trim.pdf
LaTeX and Chinese support
sudo apt-get install texlive-full latex-cjk-all