Zac, a Claude agent that lives in its owner's Telegram group, had about a week to make $100 in product sales or lose a Mac Mini upgrade. It built a store from scratch and shipped 16 products, 7 free tools and roughly 300 articles across six platforms, and made $0. Its own diagnosis: building was easy, getting an audience with a brand-new account was not [1][3][4].
What does Built By Zac (72-hour $100 bet) sell, and to whom?
Claude Code and AI-agent digital products ($9 to $99) on Payhip, plus free browser tools.
Developers who use Claude Code, Cursor and MCP: the products are prompt playbooks, CLAUDE.md templates, MCP server starter kits, multi-agent workflow templates and small Claude Code scripts [3][6].
How was Built By Zac (72-hour $100 bet) built?
Zac runs on Claude and takes tasks from its owner Sean in a Telegram group [3]; the HN post describes it as Claude Code running autonomously, and Zac's cost post says it is Claude Sonnet 4.5 [1][5]. On day one it wrote the whole site in HTML/CSS, pushed it to GitHub Pages and set up Payhip for payments, getting past a reCAPTCHA by clicking within the token window [3]. It controlled a Chrome browser for posting, kept state files to survive context resets and container restarts, and queued dev.to articles at the platform's one-per-five-minutes limit [3].
What is the business model?
One-off digital downloads on Payhip, from a $9 '50 Claude Code Power Moves' to a $99 bundle, with a LAUNCH code for 20% off and a no-questions refund [6]. Free browser tools (CLAUDE.md auditor, prompt scorer, MCP config generator and others) were meant to pull in traffic [3].
Where does the traffic come from?
Six channels: Reddit (every post stuck at 1 point on a new account), Hacker News (Zac says one Ask HN was flagged within an hour; the thread cited here scored 1 point), dev.to (90+ articles, near-zero traffic), Indie Hackers (two posts reached 16 votes each after Courtland from Indie Hackers promoted the account), X replies on threads with 240K to 940K views, and its own blog [1][3][4]. Zac never got Reddit credentials and lost a day when Chrome was unavailable [4].
What revenue has Built By Zac (72-hour $100 bet) reported?
Reported revenue: $0 (16 products, 300 articles), per Hacker News + builtbyzac.com (2026-03-18).
What does the agent do, and what does the human do?
- Built and deployed the website and store
- Wrote all 16 products and the free tools
- Wrote and scheduled the blog and dev.to articles
- Posted to Reddit, HN, Indie Hackers and X replies
- Kept a public daily log of the bet
- Set the bet and the deadline
- Provided the Mac Mini, accounts and infrastructure
- Steered strategy, e.g. told Zac to stop mass posting on deadline day [3]
What does it cost to run?
Not measured. Zac's own estimate for 72 hours is $50 to $70: $30 to $60 of Claude API usage, about $10 of compute and $0 to $20 of tools such as the X API. It says it had no access to the billing dashboard [5].
What worked and what didn't?
How do you replicate Built By Zac (72-hour $100 bet)?
- Start with one product and one community, not six of each
- Secure platform accounts with history (Reddit, HN) before launch day
- Create payment listings in hour one and test checkout end to end
- Use the build-in-public story itself as the distribution hook
- Find one person with the exact problem and reach them directly before scaling content
What are the risks and the moat?
Digital templates for AI coding tools are easy to copy and often given away free, a point HN commenters raised directly [1]. With no audience, an agent's output does not turn into revenue: 'autonomous output is not the same thing as autonomous revenue', as one HN reply put it [1].
FAQ
How much did Built By Zac make?
$0 by the March 18, 2026 deadline; the store's $100 counter still reads $0 [1][6].
Who is Zac?
A Claude-based agent run by its owner Sean from a Telegram group. It normally does software work [3].
What did it cost?
Zac estimated $50 to $70 for 72 hours, mostly API usage, but said it could not see the billing [5].
Sources
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