zbrock

Yep!

We spent a lot of time tweaking skills, doc files, and prompts. I’d say that was our primary activity as engineers. Our job became tweaking the harness every time we got code or results we didn’t like. Eventually we were pretty happy with most agent runs, but we were always happy to just throw out ones that didn’t meet our standards. I think more than half didn’t.

This was primarily an Electron app with some small hosted backend services

1. Yes! Many teams internally have adopted a lot of the same practices we outlined in the blog post. Ryan has also been spending time both internally and externally helping companies figure out how to do this in their code bases.

2. Hmm, kind of. There have definitely been issues the models can’t one shot. But we still use Codex to write all the actual code with human guidance.

3. More agents :) Some teams are experimenting with centralized Agent mediated integration queues, others use normal merge queues, many have local Codex threads that monitor CI to resolve and land conflicts or failures.

4. Today’s models and codex app. We started doing all this with gpt-5 and codex-cli. The tools today, 9 months later, are so much better than what we had then.

Correct on the first part, partially correct on the second. LOC is a bad metric, but it is at least a legible one. Lots of people working on better ways to measure Software Productivity!

At the time we wrote the article we hadn’t released the product and weren’t ready to talk about it. It was an internal prototype that looked very much like the current Codex app.

Hello! I’m one of the three engineers who write this piece. Happy to answer questions.

They did that already in the 80s, they're called Incentive Stock Options

"What are the current salary bands at your company for someone with my level of experience?"

We sync your items, settings and payment history between multiple devices. That was...not easy.

Thank you! Our in house video team is pretty awesome.

Do you know of any high traffic sites that aren't?

We pair a fair bit at Square. We require that all code either be paired on or go through code review, but let each team decide their own process. Some of the teams pair 90+% of the time, and some pair only infrequently.

San Francisco, CA

Square (https://squareup.com/jobs)

We're going to change the way people pay. We've got some big backers (http://www.crunchbase.com/company/square), a bunch of really smart people and a product that people absolutely love.

Email me (zach -at- squareup.com), or apply through the site if you're interested.

We don't store any data on the device per PCI security standards. We mention this on our security page: https://squareup.com/security

We're working on it!

Definitely on our todo list.

Also, we're hiring: https://squareup.com/jobs

Square is a great place to work. It's an awesome team that's working on solving a big and real problem. On the server side we're mostly writing Ruby and practice pairing, TDD and aggressive refactoring. We're also looking for talented iOS and Android developers for the client side. If all this sounds interesting, feel free to email me: zach -at- squareup.com

I think you underestimate the complexity of the payments space. It's pretty heavily regulated by the federal government (OFAC, AML), the payment card companies (MATCH, PCI) and local governments (MTLs, tax laws). Going through the audit process for PCI in particular is pretty rough. On top of that, designing, building and mass-producing a physical device affordably is pretty tough to do.

All that being said, you should definitely give it a shot. Working on payments technology is a blast.

Square's goal is to be device agnostic. We're definitely thinking about NFC and we're looking forward to NFC capable phones hitting the market. Hopefully the Nexus S will get upgraded to be transmit capable soon and we can do some neat things with it.

If you really want to dig into objects in irb, you should check out https://github.com/matthew/method_lister

It'll give you a really good idea of where all those methods on your objects come from.