Software engineer · Building in public
Charles McQuain.
A senior engineer using AI to ship real products and side income — and writing about it honestly: real workflows, real costs, real numbers.
Latest Real Numbers: a newsletter for engineers building on the side- Years shipping production software
- 07 Years shipping production software
- Products & sites live in the portfolio
- 06 Products & sites live in the portfolio
- Visits served by an award-winning build
- 1M+ Visits served by an award-winning build
- My first book — out now on Amazon
- Live My first book — out now on Amazon
Field Notes
The latest.
All posts
Real Numbers: a newsletter for engineers building on the side
I launched Real Numbers — the newsletter that replaces my original one here. It documents my side income publicly: every stream, every two weeks, no omissions. First issue: July 1, 2026.
Read the postThe Real AI Side Hustle Is Live on Amazon
Why I cut my AI book from 17 chapters to 11 before I finished it
I gave myself 60 days to bootstrap side income with Claude Code
The Book
Out now on Amazon
The Real AI Side Hustle.
A senior engineer's no-hype field guide to building a real side-income asset with AI tooling. Honesty is the floor; the edge is proof — real, dated, redacted dashboards from live projects, and the AI-search shift most books still ignore. Drafted in the open: the blog is the working log, the book is the distillation.
Who it's for The AI-curious person with a day job who wants a real side-income asset — not engineers, not marketers.
What you'll get A real method to build an AI-assisted content site, taught through my actual projects — real numbers, real dashboards, failures included.
About
Still in the
codebase.
I'm Charles — a senior software engineer, seven years into building platforms that handle millions of requests, AI systems doing real-time product Q&A, and the kind of infrastructure overhauls that quietly save companies a lot of money. I still do that job every day.
In the margins around it, I use AI tooling to build a small portfolio of products and content sites — and I publish the honest version of how that's going: the method, the systems, and the numbers, recently distilled into a book. No dream-selling, no cherry-picked screenshots. If I write about it, I shipped it.
Shipped & public
The Real AI Side Hustle
My first book — the honest results of testing the AI side-hustle playbook myself, with real, redacted dashboards instead of theory. Out now on Amazon.
Real Numbers
A biweekly newsletter for engineers building on the side — honest tool reviews, AI workflows I actually use, and full income documented publicly. No omissions.
Vaultano
Secure, self-destructing credential sharing for developer workflows. Secrets live in memory only — never written to disk.
Supapoints
Tracks the credit card statement credits and benefits you'd otherwise forget to use — plus a Card Advisor that recommends the right card for your actual spending habits.
charlesmcquain.dev
This site — handcrafted, zero-JS-by-default, 95+ Lighthouse. The build log is the first post on the blog.
Collaborate
Let's build something.
Some of the best things I've shipped started as a conversation with someone chasing an idea who needed another builder in their corner. If you're working on something interesting — a product, a partnership, a sponsorship, or an idea you can't put down — I'd genuinely love to hear about it.