Greetings, all!
I’m currently a Saitama-based English teacher thinking of transitioning to front-end development, already in the country with an Engineer Specialist in Humanities International Services status of residence. What programming languages are good to know? I know quite a bit of HTML and CSS plus a smattering of JavaScript, all of it self taught and still learning more. How much of a language should you know? Also, do employers here in Japan generally look for official qualifications or for a portfolio? I only have one rather simple JavaScript written myself. Thanks.