If Indeed.com job search results are anything to go by there's also EBay, Verizon, Morgan Stanley, Northrup Grumman, Slack, Nike, JPMorgan.

Searching around the web I see other users including Netflix, Tumblr, Xerox, Sony, Siemens, UBS, Ask.com, AT&T, Bloomberg, IBM, Bank of America, Amazon, TomTom, NASA, Credit Suisse, Autodesk, Nokia, Apple, AOL, eHarmony, Gawker, HSBC, Klout, Novell, SAP, UBS, Allan Gray, Telefonica, Weather Channel, The Guardian.

https://www.quora.com/What-startups-or-tech-companies-are-us...

http://www.indeed.com/jobs?q=scala

https://www.quora.com/Any-companies-using-Scala-in-Berlin?sh...

Actually this misses Zalando. One of the biggest shop in germany.

Impressive list.

Most of those companies use a bunch of technologies, Scala being only a small part of their stack. Only a few of those companies use Scala as their main language.

Is it really common for companies to have a single dominant language though? It seems that most companies have their eggs in four or so baskets.

Yes, totally. I'm talking about their core language. LinkedIn's core language is Java. Google's main languages are C++ and Java. Pinterest is mostly Python. Quora's core is Python. Stripe's core is Ruby.

I'm curious, why Scala over all other options?

It's a fantastic language. It combines the conciseness and readability (if you stick to sensible method names) of Python with the safety of OCaml and the performance of Java. It combines the type-level power of Haskell (i.e. the ability to explicitly sequence effects) with traditional OO inheritance/subtyping and performance behaviour you can reason about (helped by the JVM's well-established profiling/instrumentation support). If you want to use a single language for everything, it can scale up to critical core codebases and down to throwaway scripts / interactive notebook-type use. What else would you use?

> What else would you use?

Oh, no, I was asking mostly as a noob. I've since decided to have a go at learning Scala, and your answer reinforces that decision.

AFAIK, quite some components (Hadoop, Kafka, Spark, etc) of a typical big data stack are JVM based. Scala is JVM. And quite some people hate Java. That could be an answer.