I've been paid by Dzone.com (for both writing and editing) and TechBeacon. I was published a few times by Lifehacker although I don't remember if those were paid (and they aren't what I'd consider a tech site).

Reaching out to site editors with a couple samples of work could find you getting work published. As a freelance software developer, getting paid to write is nice, but just getting published can help increase exposure and lead to more incoming requests for project work and improved reputation.

Auth0 at least used to pay for blog content.

I am not sure if they still do that though - last time I did that was about 2 years ago.

I wrote about their tech and how to integrate it in a different stack. I believe they paid about 200 USD for it.

I'd look it up but I am on mobile atm so it's not convenient. Might be worth to look up their website if it interests you.

digitalocean.com, and other nich tech websites. it usually helps to have a couple example essays/posts before asking to be paid for content.