I donno why you're being downvoted, it's a questionable decision and probably the company would have been better off with Python/PHP/Node. Hiring and onboarding are extremely important for a startup. You know what else? Finding answers to common questions on Google/Stackoverflow; I am now working with Ember and can tell you guys you take a 50% productivity hit by using a tool that's obscure on Google. Sure once you become super familiar with a tool that matters less, but that takes time. Much more time. React/Angular may be an inferior tool to Ember but the fact that you can get answers to almost any question is priceless. The community size is super important. The frameworks are super important (is there a Closure equivalent to Rails/Django/Laravel in community size, in battle testedness? I really doubt it).
That being said, I salute these brave companies for sticking to these obscure languages. Do we want to live in a world where there's only 3 languages to do everything? Even 10 sounds boring. Hell, even a fantastic tool like Ruby is considered Niche in certain parts of the world. I don't want a world without Ruby so I don't want a world without Closure.
> Hiring and onboarding are extremely important for a startup.
If you're a small company, you usually cannot afford to hire "mediocre" talent. It is much more expensive to undo the crapola they'd implement. Trying to hire those who are at least interested in learning and using languages like Clojure, Rust, Haskell, Elixir, Elm, etc., is a very good quality filter. ROI from hiring a smaller number of Clojure devs, rather than a few more "regular" engineers - is much higher.
> Finding answers to common questions on Google/Stackoverflow;
Clojure gives you far fewer reasons for Googling things than other language ecosystems. It is dense language and inspires you to write smaller functions, decreasing the surface area for the problem. Most of the time, asking questions in Clojurians Slack sends you halfway through the solution.
> I salute these brave companies for sticking to these obscure languages
They do not choose Clojure for the shtick; Clojure is a highly pragmatic and immensely productive instrument. There are many "success stories" with small and medium-sized companies. A few large companies like Cisco, Apple, Walmart, et al., actively develop in Clojure.
The same can be said about the engineers. They don't choose Clojure because "they hate Java". You can check any Clojure surveys of the past. Most Clojure engineers are experienced and "tired" developers. Seasoned hackers who have seen the action. For most of them - Clojure is a deliberate choice. Many of them landed in it after trying various other alternatives.
> Trying to hire those who are at least interested in learning and using languages like Clojure, Rust, Haskell, Elixir, Elm, etc., is a very good quality filter.
That's not my experience. It doesn't say a whole lot, it just says a person is bored a bit and is confident in his ability to learn new things, you can filter for learning abilities by looking at what the person achieved; doing new stacks is just one metric. Also it's sometimes the type of people who care more about learning/trying new tech on the job than actually helping the business (for exmaple by introducing GraphQL because they read about it in a blog and it looks cool, not because they really think the business needs it).
That being said, I salute these brave companies for sticking to these obscure languages. Do we want to live in a world where there's only 3 languages to do everything? Even 10 sounds boring. Hell, even a fantastic tool like Ruby is considered Niche in certain parts of the world. I don't want a world without Ruby so I don't want a world without Closure.