I used Obsidian's Daily Note Core Plugin in conjunction with the Templater Community Plugin. It creates a new markdown file in .../DailyLog/YYYY/MM/DD.md using a template that automatically adds some assorted frontmatter (like current company name or project) and a full date (Thursday, October 27th, 2022) as the H1 header. Then I just use the file to keep random notes or as a scratch pad. I don't enforce any organization, so sometimes it's just a SQL query that I had to run 35 times that day, sometimes it's a todo list, and other times is a full narrative log of my day and the issues I was running into.

I used to do this in Sublime, which was fine, but Obsidian let me automate the date and frontmatter stuff, which made my life marginally easier. The point though, is that Obsidian is not something I'm locked into, which is nice.