A lot of people here are recommending stacks that have worked for them, or cautioning against over-engineered stacks that didn't. All of that is useful, but I'd boil a lot of this down to one simple axiom:

If you're a professional engineer and you're starting a tech side project with the goal of shipping - use what you know.

I do a lot of work with node, cloudfront, s3, and React for my day job. All of my side projects are built on node, cloudfront, s3, and React. This works well for me because my goal with side projects right now is to be productive, not to learn new tech.

An important clarification is that I use the tech that I use in my day-to-day, not what my company uses. Just because I have coworkers who know kubernetes back-to-front doesn't mean I do!

Also, there's nothing wrong with doing side projects with totally crazy/new tech stacks as a way to explore and learn new tech. I just think it's good to be really intentional with whether the goals of a project are educational/process-oriented or results-oriented.