How do websites use multiple languages ​​for their backend?

Question

Backend

Can you please tell me how some sites use multiple languages ​​for the backend? How is it generally done?

Answer 1

1. "Historically."
First they wrote on one. Then there was an idea to write on another, but they did not master it to the end. On the third write because of the lack of specialists in the old two.
2. Architectural feature.
There is a division of functions, which also imposes technical restrictions on individual parts, and it becomes more profitable to write them in different languages. Crushers in C, router in Python.

haha

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