Comment by Glench

Since the page didn't seem to link to it, here's a really great article about using SQLite in production for moderately-sized web apps: https://blog.wesleyac.com/posts/consider-sqlite

That article, along with the ability to have streaming backups with Litestream and not wanting to pay for a separate DB server, inspired me to use SQLite in my SaaS four years ago. I've been enjoying the operational simplicity a lot although there is not a lot of community documentation currently about tuning SQLite for web app loads. My app does about 120m hits a month (mostly cached and not hitting the DB) on a $14/month single-processor DigitalOcean droplet.