Walmart acquired a company called Kosmix in 2011 and spun it out as a research division called @WalmartLabs [1].

Walmart acquired the online retailer, Jet.com in late 2016 which still has their own engineering team (using a lot of F#)

Stuff coming from @WalmartLabs is almost always real stuff that Walmart is using in production (website, apps, etc.)

[1] https://en.wikipedia.org/wiki/@WalmartLabs