All the companies my friends or I worked in, which had non-English codebase, were a complete garbage. So my tip is to refactor and translate all of it at once or leave the company

No, it is not. Code is a text which is designed to be understood by machines and humans. If you write your code in your native language, you make it hard to understand for those, who do not speak this language.

I used to work in teams where 100% of devs, users and managers were Russian-speaking, and we still wrote our program in English, because writing transliteration or using Russian terms (even though Russian language has it’s own broad and deep software development vocabulary) in English programming language would result in a mess nobody would understand. Even if we wrote everything in a Cyrillic alphabet and wrapped every dependency into Russian language wrapper, we would still have an ugly fusion of two languages.

I didn’t say that every English codebase is good.

I am sorry, but how do they program in Elixir? Language constructs, documentation, tutorials, libraries, maintainers, conferences: all in English. How do they explain what does the Supervisor or GenServer mean?

I started programming when I was a kid and I didn’t know any English back then, so I learned terms and gave them my own special meaning (I can sometimes pronounce “header” as “heedr”). But when I learned English, it all finally connected together like a huge puzzle. I understood that I had know only like 50% of what actually was meant in the first place.

If you program in Elixir without knowing English, you’re just combining magic words with a hope that this time it works

I’ve had to do something similar once. I had a gig where I had to migrate the data from one ERP system to another, but the source ERP system code (names, etc) were all in French and I didn’t have access to any technical resources familiar with the source ERP system to call on… and I don’t speak any French at all.

So I did as @dimitarvp has suggested and used online translators. I did three things to get through: 1) I’d take words from the code and translate them; 2) I’d take the English names (I speak English natively) of the concepts I knew should be in an ERP system and translate those into French; 3) I used multiple online translators since different translators might give me different answers (and thoroughness).

Items 1 and 2 above helped where the French words had been abbreviated in some way for brevity and so couldn’t be translated directly from what was in the code.

In the end I got through it and it wasn’t that bad. Mind you I did have that advantage of really knowing the kinds of things that should be there, being able to evaluate if the data matched my assumptions, and I also had an English UI that I could validate against as well.