Written for those who aren't sure when SQLite is a good solution for a website DB
SQLite should be OK for a website that doesn't require many writes to the DB.
From the SQLite project website: https://www.sqlite.org/whentouse.html
SQLite will normally work fine as the database backend to a website. But if the website is write-intensive or is so busy that it requires multiple servers, then consider using an enterprise-class client/server database engine instead of SQLite. (snip next paragraph)
SQLite supports an unlimited number of simultaneous readers, but it will only allow one writer at any instant in time. For many situations, this is not a problem. Writers queue up. Each application does its database work quickly and moves on, and no lock lasts for more than a few dozen milliseconds. But there are some applications that require more concurrency, and those applications may need to seek a different solution.