[arp242]

Also, from Wikipedia:

"In February 1998, Ericsson Radio Systems banned the in-house use of Erlang for new products, citing a preference for non-proprietary languages. The ban caused Armstrong and others to make plans to leave Ericsson. In March 1998 Ericsson announced the AXD301 switch, containing over a million lines of Erlang and reported to achieve a high availability of nine "9"s. In December 1998, the implementation of Erlang was open-sourced and most of the Erlang team resigned to form a new company Bluetail AB. Ericsson eventually relaxed the ban and re-hired Armstrong in 2004."

Not wanting to rely on a fairly esoteric in-house language makes some sense.

Since then things have changed significantly of course.

[znpy]

> Not wanting to rely on a fairly esoteric in-house language makes some sense.

Not necessarily… thst language clearly was a competitive advantage

[ilikehurdles]

Reminds of Paul Graham’s essay on Lisp being a secret weapon for Viaweb, Beating The Averages[1].

[1]: http://www.paulgraham.com/avg.html

[di4na]

There have been second hand report of the current leadership at Ericsson saying that opensourcing erlang was the worst decision they had taken. As it would have given way a massive competitive advantage.

[panick21_]

They are idiots then. Erland would simply not be as good if it was not open. companies not understanding open source is just so annoying.

[di4na]

Possibly but...

Nearly 80% of OTP development is and has always been, done internally at Ericsson. And they barely use the libraries from the outside world. From inside Ericsson, erlang look a lot like a proprietary language

[arp242]

There's pros and cons to these kind of things. "Best tool for the job" reasoned purely from a technical point of view isn't necessarily the "best tool for the job" when everything is factored in.

It's hard for me to judge one way or the other; I wasn't at Ericsson in 1998, or indeed, ever at Ericsson. I just figured that the language wasn't open source at the time and that they came back on their decision just a few year later were important bits missing from the previous comment.