If you have a line like this in your Apache config:
Redirect / example.com
You should add the missing trailing slash (example.com) or you'll create an open redirect.
sponge is a really handy UNIX tool (part of the moreutils package) to avoid creating a temp file when using formatting tools that don't support in-place editing. For example: json_reformat < example.json | sponge example.json
Interesting discussion by @danluu of the tendency to assume that things are simpler than they really are when one doesn't know very much about a field: danluu.com/cocktail-ideas/