I started using a PostgreSQL database with GnuCash instead of a file, and set up a weekly cron job to dump the database to a file. Here's the script:

#!/usr/bin/env bash

# Requires that ~/.pgpass exists, is chmod 600, and contains a line like:
#
# 127.0.0.1:5432:*:gnucash_user:my-secret-password

pg_dump -h 127.0.0.1 -U gnucash_user -d gnucash_db -Fc > ${HOME}/gnucash_$(date +%F).dump

I'm probably going to modify this script to check that ~/.pgpass exists.

Any other changes you think I need?

Here's the explanation for why the wiki (and others) are currently down:

Unfortunately code.gnucash.org http://code.gnucash.org/, which provides these mailing lists, the wiki, the bug tracker, nightly builds, and some other services, has been hammered the last several days by bots scraping the wiki and bug tracker resulting in connection timeouts for everything. In order to reduce the impact Derek and I decided to disable access to the wiki and bug tracker. They’d been rendered useless anyway so weren’t doing anybody any good and this allows the rest of the services to work normally.

Regards, John Ralls