The two companies I am currently obsessed over from a product standpoint are Shopify and Duolingo. I can’t read and learn enough about either.

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For Duolingo, here’s some good reading (thanks @sa ) for the first link:
- https://spectrum.ieee.org/duolingo
- https://open.substack.com/pub/lenny/p/how-duolingo-reignited-user-growth

For Shopify the acquired podcast episode remains the single best reference material I’ve found. https://www.acquired.fm/episodes/the-shopify-ipo