At 13:29 on 20 September 2026, I made the first commit to an empty Vouchernaut repository. By 12 October, vouchernaut.com had fifteen live products, from checked codes for 995 UK shops to a brand platform with its own Shopify app. The 22-day rebuild produced 772 commits and about 530,000 lines of code, including 145,000 lines of tests.
I did the product, design, engineering, operations and selling. Agents did most of the typing; I wrote the specs, made the calls and checked the work. I kept the full feature and decision record in 
a 40-page case study PDF.
The first Vouchernaut
In 2016, I worked on Vouchercloud's paid search team, inside an international voucher marketplace. Most of the work was finding offers, checking them and writing much the same page for the next store. I wanted to test whether software could write those pages and win search traffic without a content team.
Vouchernaut listed offers for more than 100,000 brands. Each brand's page came from data rather than hand-written copy. It reached 250,000 sessions a month with no paid spend and 90% margins. I ran it alone for six years.
The software under it changed three times. It started on WordPress with a coupon theme and a magenta rocket. By 2018, the homepage led with an exclusive Theatre Tickets Direct code, as the Internet Archive's October 2018 capture shows. Getting that code took a conversation with the brand and gave readers an offer no other site had.
In October 2019, I relaunched on Gatsby with a headless CMS and introduced an astronaut mascot. Next.js followed in January 2022. Vouchernaut ended in November 2022.
The astronaut with the pink V on his chest is still the mascot. He's called Vinny now, and he's made of clay.
Testing the approach with Toolzilla
In 2024, I built Toolzilla to test the same approach to building pages from data with modern AI tools. It collected design templates from more than 50 marketplaces, but most had no API, so I scraped them. Their categories differed too: what Framer called landing pages, Webflow called marketing sites. I used an LLM to sort the templates into one taxonomy from their visuals and text, with no manual work.
With 50 sites to scrape, something broke every day. I spent whole weekends fixing scrapers, so I built ones that repaired themselves. When a scraper failed, an LLM read the new page structure, rewrote the extraction code and tested it, and the fix went live only if it passed. That handled about 80% of the maintenance and turned a full-time job into a weekly check-in, but keeping more than 50 scrapers going would still have needed a hired team or expensive services that killed the margins. I stopped Toolzilla and took what it taught me into client work.
Why I came back
By the time I returned, voucher sites had an attribution problem. In December 2024, a YouTube investigation alleged that PayPal's Honey extension took credit for sales referred by creators and publishers. In January 2026, Rakuten Advertising removed Honey,
impact.com followed, and
Awin said its investigation had confirmed breaches of its publisher policies. Brands had a fair question for every voucher site: would the sale have happened anyway?
Search was changing too. From 2024, Google's site reputation abuse policy hit publishers' voucher sections hard.
OpenAI launched Instant Checkout in ChatGPT in September 2025. A bare list of codes gives an assistant little to work with; checked prices and full costs give it plenty.
In 2020, I'd told brands in writing that a small voucher publisher could add sales a brand wouldn't otherwise make and show its working. I hadn't fully proved it, so I set three rules for the new Vouchernaut:
- Help before the choice. Build comparison tools, guides and a shop that help people decide what to buy and where.
- Make prices stand up. Show "down from" only when the old price held for 28 days; show the total beside every monthly price.
- Label every click. Carry one of ten channels on every click to a store, so the brand can see what sent the sale.
Agents meant one person could build all of it. I'd tried a first version from June to July 2026 and kept its ideas but none of its code. The same way of working rebuilt Benson in ten days.
Two sprints, 22 days
The first sprint ran from 20 to 27 September and produced 463 commits. It covered articles, store pages, the editing studio, accounts, the cashback ledger, the Chrome extension, the design system, group cashback pages and the advertising rate card.
The brand platform took the two biggest days. On the morning of 26 September, I planned it in one sitting: locked decisions, a backlog and numbered product requirement documents, or PRDs. Each PRD stated what a feature did, why it existed and what done looked like. Agents built against them over the next 26 hours: a console, partner API, embeddable widget and Shopify app.
Between sprints, I joined brands' programmes, checked each approval before giving it a page and wrote store pages. The first 76 went live on 1 October.
The second sprint ran from 8 to 12 October. Its 295 commits delivered most of what shoppers see today. The shop arrived on 9 October; phones, broadband and energy followed on the 10th. On the 11th came polls, maps, price watch, the Weekly, What's On, airport parking, software and the discount hubs. The server for AI assistants and the press kit landed on the 12th.
How I ran the agents
I wrote the build rules and decided what done meant. Agents typed across 203 Claude Code sessions and 615 subagent runs, many in parallel. Each session had its own copy of the repository, so separate features could move at once. Codex, OpenAI's coding agent, worked alongside them and rendered Vinny's clay scenes to the house style I set.
Three controls kept that work aligned:
- A spec for every feature. Each PRD arrived before or with its code, so a session started with a defined result.
- One manual for every session. It records what each feature does, its rules for shoppers and its legal limits. I add settled decisions there so the next session follows them.
- Nothing merges unseen. I check each result against its spec before it goes live. If the voice or design is wrong, I return it with a note and add that note to the manual.
Fifteen products on one catalogue
All fifteen live products share one catalogue of UK stores. The homepage on 12 October shows most of them and their live counts.
- Store pages and codes for 995 UK shops. Each page has an introduction and shopping guide; codes arrive through the day from the stores' own programmes.
- The shop and price watch cover 5,220 products from 21 stores, priced with their codes. Watching a product sends one email the morning after its price drops.
- The phone finder covers 103 phones and 235 SIM-only plans. It prices the whole contract and puts
every announced rise under the monthly price.
- The broadband checker covers every UK postcode using Ofcom's open data. Energy comparison costs suppliers' published tariffs against the price cap in all 14 regions.
- What's On covers 21,087 events, shows and things to do in
- Airport parking covers the UK's main airports. There's also a software section, 76 researched guides with live shop grids, maps and polls inside them, and Vouchernaut Weekly, a Thursday deals email.
- Discount hubs cover students, the NHS, blue light, teachers, the military and key workers. Shoppers can
- Group cashback lets clubs, schools and charities raise money from supporters' everyday shopping.
- A Chrome extension, and a server for AI assistants listed in the official MCP Registry, so assistants can look up live codes and prices.
- Vouchernaut for Brands, at
brands.vouchernaut.com, has verified offers on a brand's own site, placements, an offer hub, reports, plans from free to £199 a month and a Shopify app.
Group cashback is the part I'm proudest of. Each supporter chooses the share their group gets, and the group's page shows its goal and progress. A school or football club can raise money from shopping its supporters were doing anyway.
The rules I put in the product
Agents wrote the code, but I decided how Vouchernaut treats shoppers and brands. These decisions live in the code or the manual:
- No price without fees. A ticket seller shows no price until its fees are checked. A car park shows the total for the shopper's dates or nothing.
- Commission does not set the order. A provider that pays nothing stays listed, and every phone page explains how deals are ranked.
- Mark paid links. Every link that can earn commission carries a visible Ad tag before a shopper taps.
- Respect brands that refuse codes. Some welcome publishers but exclude voucher sites. Their pages carry no codes or cashback and say plainly that the brand's own price is its price.
- A click requires a tap. The extension sends a click only when a shopper taps, never when they copy a code. It stands aside when another publisher sent them.
Two design systems and one clay astronaut
I designed the site as well as the product. Its design tokens and components have their own page; the brand console has a separate, equally documented system. New pages follow the phone pages' visual language: calm, plain and with prices set in mono.
Vinny has been the mascot since the 2019 relaunch. In 2026, I remade him in clay with the same helmet and pink V, set among pastels and concrete blocks. He's on the homepage, in the press kit, on each discount hub in a uniform of his own and on the case study cover.
What one person still had to do
Vouchernaut was a one-man band in 2016: one site doing one thing because I could only do one thing well alone. In 2026, I made product decisions, designed, read the law and network terms, joined programmes, wrote store pages and checked each result before release. The agents didn't make those calls. They let me make them across a whole business in three weeks and see the work live the same day. I now work this way on my own products and other people's.
vouchernaut.comVouchernautChecked codes for 995 UK shops, a shop, comparison tools for phones, broadband, energy and parking, and What's On across the UK.
Research and sources
Checked 2026-10-12. Next review: 2027-04-12. Listings and availability can change.
vouchernaut.com, captured 22 October 2018
Internet Archive · Checked 2026-10-12 · Primary source
The WordPress version of Vouchernaut, leading with its own exclusive code at Theatre Tickets Direct.
Internet Archive · Checked 2026-10-12 · Primary source
The Gatsby version of Vouchernaut on Black Friday eve 2020, with the astronaut mascot and the pink V.
Rakuten Advertising becomes first major network to remove PayPal Honey following attribution controversy
Affiverse Media · Checked 2026-10-12 · Secondary source
Rakuten Advertising removed Honey from its network in January 2026.
impact.com just kicked Honey off its network
PPC Land · Checked 2026-10-12 · Secondary source
impact.com removed Honey from its network in January 2026.
Awin Group statement on Honey investigation
Awin · Checked 2026-10-12 · Primary source
Awin said its investigation confirmed breaches of its publisher policies by Honey.
Publisher shopping revenue dealt blow on eve of Black Friday
Press Gazette · Checked 2026-10-12 · Secondary source
Google's site reputation abuse policy cut UK publishers' voucher-section revenue.
PPC Land · Checked 2026-10-12 · Secondary source
OpenAI launched Instant Checkout in ChatGPT in September 2025.
Vouchernaut · Checked 2026-10-12 · Primary source
The live products and their counts on 12 October 2026: 995 UK shops, 5,220 shop products and 103 phones.
Vouchernaut · Checked 2026-10-12 · Primary source
Every monthly price is shown with its upfront cost, length, total, seller and announced rises.
Vouchernaut · Checked 2026-10-12 · Primary source
What's On covers 86 places across the UK, with 12,020 events and 9,067 things to do on 12 October 2026.
Vouchernaut · Checked 2026-10-12 · Primary source
The discount hubs for students, the NHS, blue light, teachers, the military and key workers, verified once.
Vouchernaut · Checked 2026-10-12 · Primary source
Groups raise money from their supporters' shopping, with each supporter choosing their share.
Vouchernaut · Checked 2026-10-12 · Primary source
The brand platform: verified offers on a brand's own site, placements, reports and a Shopify app.
Vouchernaut · Checked 2026-10-12 · Primary source
Vinny the Vouchernaut, then and now, and the figures for 12 October 2026.
