Came here to also throw in a vote for it being so much easier to just use SQLite. You get so much for so very little. There might be a one-time up-front learning effort for tweaking settings, but that is a lot less effort than what you're going to spend on fiddling with stupid issues with data files all day, every day, for the rest of the life of your project.

Even then... I'd argue for at least LevelDB over raw jsonl files... and I say this as someone who would regularly do ETL and backups to jsonl file formats in prior jobs.