Duolingo is a language learning platform with over 200 million users. On a daily basis millions of users receive customized language lessons targeted specifically to them. These lessons are generated by a system called the session generator.

Andre Kenji Horie is senior engineer at Duolingo. He wrote about the process of rewriting the session generator, moving from Python to Scala and changing architecture at the same time. In this episode Adam Bell talks with him about the reasons for the rewrite, what drove them to move to Scala and the experience of moving from one technology stack to another.

Show Notes

Rewriting Doulingo’s Engine in Scala

Jobs at Duolingo

Transcript

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