Never commit invalid json again! chmod +x, and add to .git/hooks/

pre-commit

#!/bin/sh

for n in `git status --porcelain | grep -E '^(M|A)' | grep -E '\.json$' | awk '{print $2}'`; do
    if ! python -m json.tool $n > /dev/null; then
      echo "$n failed to pass json sanity checks"
      exit 1;
    fi
done