Why do companies write their internal languages?

Question

Work organization

Hi all. Several interviews have already passed, and in many companies they develop in their own languages, created within the company. So the question is, what is the benefit of such an approach?

Answer 1

I know one office with my own language and saw pieces of their code, but I didn’t work with it myself - God bless.
as I understand it, it all starts with harmless and very useful domain-specific languages, such as a convenient dsl for describing some forms. this saves a lot of boilerplate and everyone really likes it, but a few forms with complex logic cannot be translated yet, because there is a little lack of functionality. of course, adding a few features to the language is not a problem, and so after a few years it turns out that everything is now written in this self-made language, which now knows almost everything, losing its subject orientation along the way, and acquiring its own boilerplate.
I see two pluses for the office itself: firstly, the customers of this system cannot drastically change the vendor for software support and you can milk them for many years until they decide to rewrite everything entirely, from scratch. secondly, the developers who have worked for 10 years each in this language are in no hurry to change jobs, because no one in the world needs this miracle language anymore.
in theory, if such an opportunity was originally laid down, it probably can facilitate porting to different platforms (it was desktop, it became web, and then mobile, while the old application code remained working), but this also does not happen for free, so all options will be far from ideal.
the rest is all rubbish. in general, this can only be justified under very specific, semi-monopoly conditions.

Answer 2

There is quite a lot of old code. But there are no resources to rewrite it in a new framework.
Therefore, the easiest way is to write a compiler into an intermediate interpreted language, and then adapt the interpreter of this language to the framework.
For example, from Fortran to Python.

Answer 3

Code protection/project secrecy.