Every side project I've shipped in the last few years has hit the same wall at roughly the same point. The app works, it runs on a single cheap VPS, and then I need to send an email after the request returns. Or resize an image. Or run something every night at 3am.
The standard answer in Node land is BullMQ, which means Redis. And Redis is great. But now my "one small app on one small server" has a second service to install, monitor, secure, and remember exists when the box reboots. All so I can send an email five seconds later.
The third time I caught myself provisioning Redis for a queue that would see maybe two hundred jobs a day, I stopped and wrote vardiya instead.
The idea
If your whole app lives on one machine, you already have a durable, transactional store sitting right there: the disk. SQLite in WAL mode handles concurrent readers and a single writer perfectly well, and a job queue is mostly just "one writer claims rows atomically."
