Program · April 30 to July 14, 2026 · Closed
Corner
Payments and inventory for Toronto corner stores, and an unattended store of its own planned for 520 Barton in Hamilton. One founder built the software with two AI assistants and took a live charge. Then he closed the program on the numbers.
What Corner was
Corner built payments and inventory software for other people's stores. It also planned a store of its own, in a small structure behind 520 Barton Street. The kiosk below was built for that store, and the 520 Barton study asked whether the store could pay for itself.
How a sale moves
A sale can start at the counter, on a shopper's phone or at an unattended kiosk. Every path writes to the same ledger, which drives restocking and the daily close.
The kiosk
The unattended kiosk was built as a bench unit: a Raspberry Pi behind a touchscreen, driving a real lock. The $250-class edge computer beside it ran language and speech models on the device. In a June test, English voice commands in the common case took about 2.6 seconds end to end, under the program's 4-second bar. Payment authority stayed in the cloud.
Nineteen attacks, all held
The money loop is the software that carries every sale's money from payment into the ledger. Before any real customer, the loop was attacked 19 ways across 71 checks. All 19 held. Scenario S, in the 48-check destruction pass, found the one real bug: a key from one transaction leaking into another. It was fixed and the pass re-ran clean.
The live charge
On July 9 the bench unit charged a real $1.99 on the production payment system, and the charge showed up in the cardholder's banking app. It was then refunded, for a lifetime net of $0.
Seventy-six days of building
The build ran 76 days, from the first commit on April 30 to the close on July 14. The busiest day, May 12, had 22 commits.
Where the money goes on a $10 sale
In the model, about 70 percent of card sales at a Toronto corner store are debit taps. On a $10 tap Corner earned a 10¢ fee and paid Stripe 15¢, so it lost 5¢ on each one.
The stores it was for
Toronto proper has about 1,375 corner stores. Moneris, Square and NRS already sell them payment systems.
How many stores it takes
If Corner passed Stripe's rates on to stores and added 1 percent, it would break even at 125 to 150 stores. That price loses to Moneris and Helcim. At a price that wins stores, break-even moves past 600 stores or never comes.
Its own store, at 520 Barton
The store was to fill a 12 by 20 foot structure on a busy Hamilton corner and run with nobody in it. The 520 Barton study tested eight concepts for it, and none survived.
The core candidate, an unattended drink machine, needed 12 cups a day. The best published figure is 6.8. Even at 12 cups, its smallest real build would take 27 months to pay back, past the program's 24-month kill line. That limit was one of the kill criteria the program set before any money was spent.
The study on one page, or in full below.