Thanks for the feedback. Going open-source is something we'd consider but right now we're focused on building a tool that people love (which becomes difficult with a bunch of hobbyist developers contributing).
Also closed source isn't always bad. It's no secret that Duolingo has the world's best spaced-repetition algorithm - they will IPO for 2.4 billion soon.
Also closed source isn't always bad. It's no secret that Duolingo has the world's best spaced-repetition algorithm - they will IPO for 2.4 billion soon.