At least some of those examples are highly misleading:
> There is no better example of Erlang’s reliability than the English National Health Service (NHS). [...] Using Riak (written in Erlang), the NHS has managed 99.999% availability for over five years.
From what I could find out, NHS's Spine2 is mostly Python, with "a bit" of Erlang and Javascript. They do use Riak, but they also use Redis, RabbitMQ, Python/Tornado, Ubuntu and lots of other components.
This sentence could have said "Using redis (written in C)", or "Using Tornado (written in Python)", and still be fully correct.
> There is no better example of Erlang’s reliability than the English National Health Service (NHS). [...] Using Riak (written in Erlang), the NHS has managed 99.999% availability for over five years.
From what I could find out, NHS's Spine2 is mostly Python, with "a bit" of Erlang and Javascript. They do use Riak, but they also use Redis, RabbitMQ, Python/Tornado, Ubuntu and lots of other components.
This sentence could have said "Using redis (written in C)", or "Using Tornado (written in Python)", and still be fully correct.