What's the most pragmatic way to start a self-hosted blog?

I recommend you to look into the Jamify open-source tools which uses Ghost for your headless CMS and Gatsby for your frontend builder (I am the author of Jamify). This modern Jamstack setup gives you a fast and professional looking site at zero costs where every piece can be exchanged with something else later, so no vendor lock-in.

Another option is Grav. It uses Markdown files for blog posts and pages, so it doesn't require a database. It's possible to store a Grav project in a Git repository and basically keep the live version up to date by simply doing a git pull on the server if you want. It also provides an optional admin module that allows you to manage content in the browser

My favorite blog engine is Ghost. It's a lightweight Worpress-like engine built on the Node stack. It has a lovely CMS-style interface for your non-engineer partners to write their posts. It's open source, of course, and has fantastic documentation. You can either host it yourself, or have it hosted by them for $29/mo.

And recently, they finished an absolutely impressive set of integrations with other services... over 70, in fact, from obvious stuff like Facebook and Twitter, to business stuff like Shopify and Adsense, to content-oriented stuff like the great Cloudinary for image management and Google AMP for search engine visibility, to more offbeat neat stuff like the Ulysses writing app and Giphy for.. gifs?

As if that wasn't enough, though by default the front end is built with handlebars.js templates, you can also make Gatsby your front end engine on Ghost, so if you've been wanting to mess around with Gatsby (and it really is great) but are afraid that your non-techy partners will have a hard time, you can just use Ghost as your CMS and use Gatsby as your front end. How cool is that?

Very cool, let's be honest. Do this. I guarantee you'll love it.

Jekyll is easy to get started with, and generates a static site from Markdown files. You can have blog posts and regular pages. If your non-engineer partners can write Markdown (for example using stackedit.io, then it might be a simple solution, but the question of file management with several authors must be addressed.

I’m looking for a headless CMS to make it easier to edit a Jekyll site, but I haven’t found one that I can self-host. forestry.io is a hosted solution (the editor is hosted by them) that connects toa GitHub/BitBucket/GitLab repository to give you an editor for a Jekyll, Hugo, VuePress or Gatsby site. It’s worth a try: it’s really nice and they have demo projects that you can quickly get started with.

I still haven’t understood the point of Gatsby of JAMStack in general. Having the browser connect to an API to build the web site using client-side code: I don’t get it. You don’t have the benefit of a static site generator, not of a CMS.

My customers aren't necessarily developers

All static site generators Gatsby, Jekyll, Hugo, etc. do require some technical involvement to publish and manage posts. For your customers (especially paying customers) with no development background, I will surely stick with existing blogging engines like WordPress or Ghost. Learning to host and manage WordPress or Ghost instances is not that difficult.

Gatsby can take markdown files and they live in the repo. You would tell gatsby where to look for them and it would do the rest. That means they’d only have to learn markdown to write posts.

If you want to cheapest, simplest, easiest and most robust way; write some HTML.

Gatsby’s plug-in ecosystem has some great tools for ingesting markdown, to add to what people are saying above about support for lots of different data sources. There’s even a plug-in that wraps Prism for syntax highlighting. And the md files can include raw html and style blocks, so guest authors can get as sophisticated as they want to. I did the blog on my portfolio site this way and I love it.

If it just a blog and it 's a static site, there is a bunch of hosting static site like Surge.sh, Netlify... and S3. I recommend S3 for your business because of stability, security, and integration with other services in AWS

Dev.to is open source.. So, you can use it for your own purposes.