> The NCR/Walmart relationship was fairly strained ...

Definitely. (: I didn't hold it against the hands on workers like yourself. Even (and perhaps especially) back then, WalMart was a challenging, difficult and aggressive partner.

> working on networking gear at Walmart meant that you were out at 11pm at night

That sounds about right; the scheduling I was directly aware of was very fast paced. Our Network Engineering Store Team pushed and pushed and pushed, just as they were pushed and pushed and pushed.

> Walmart must have been an interesting place to work during the late 90s, early 2000

Yup. Nowhere I've worked before or since had me learning as much or getting nearly as much done. It was an amazingly positive experience for me and my team, but not so positive for a lot of others.

> I imagine that most everywhere they had to solve problems at scale before scale was a considered a thing.

Sometimes I imagine writing a book about this, because it's absolutely true, all over Information Systems Division.

For a time in the early 2000s, we were, on average, opening up a new store every day, and a typical new store would have two routers, two VOIP routers, two cache engines, between 10 and 20 switches, two or four wireless access point controllers and dozens of AP endpoints. That was managed by one or two people on the Network Engineering side, so my team (Network Management) wrote automation that generated the configs, validated connections, uploaded configs, etc etc etc. (Not one or two people per store: one or two people for ALL of the new stores.)

The networking equipment was managed by a level of automation that is pretty close to what one sees inside of Google or Facebook today, and we were doing it 20 years ago.

> ... telecom ... prior art ...

John Chambers, the long-time CEO of Cisco, was at the time on WalMart's board of directors. He was always a bit of a tech head, and so when he came to Bentonville for board meetings, he'd often come and visit us in Network Engineering.

Around 2001-2002, we were chatting with him and he asked why we weren't using Cisco Works to manage our network. https://en.wikipedia.org/wiki/Cisco_Prime but back then it was mostly focused on network monitoring and to a lesser extent, config management. We chuckled and told him that there's no way that Cisco Works could scale to even a fraction of our network. He asked what we used, and of course we showed him the management system we'd written.

He was so impressed that he went back to San Jose, selected a group of Cisco Works architects, had them sign NDAs, and sent them to Bentonville, Arkansas for a month. The intent was to have them evaluate our software with an eye toward packaging it up and re-selling it.

Those meetings were interesting, but ultimately fruitless. The Cisco Works architects were Ivory Tower Java People. The first thing they wanted to see was our class hierarchy. We laughed and said we had scores of separate and very shallow classes, all written in Perl, C and C++.

Needless to say, they found the very 'rough and ready' way our platform was designed to be shocking and unpalatable. They went back and told Chambers that there was literally no way our products could be tied together.

> ... match to best-practices today ...

Professionally, I've been doing basically the same kinds of things since then, and I'll say that while our particular methods and approaches were extremely unusual, the high level results would meet or perhaps exceed what one gets with 'best practices' seen today.

Not because we were any smarter or better, but because we had no choice but to automate and automate effectively. At that scale, at that rate of change, at those uptime requirements, 'only' automating 99% would be disastrous.