For anyone considering building a business as an integration provider on top of Embed.ly (the only way to get embedded on Medium), you may want to follow the advice from the founder, Sean Creeley, who just sent me this:
"If your whole business relies on us, you might want to pick a different one.".
TIMELINE:
1) I ask Embed.ly if the novelty factor (existing competitor) would be an issue before building an integration for them
2) They say it'd be ok, as long as the other guidelines are met
3) I spend a month building the initial MVP and send it for approval
4) The founder replies and instead of providing guidance on what should I change to get approved, accuses me of "copying someone else's work" and that "We aren't going to argue with you on this".
Screenshots of all conversions (newest at the top):
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