Hi Matthieu,
It's an interesting concept and thanks for your introduction, just some personal thoughts:
1. `id` is still the common used
unique identifier for most tech guys
2. for concern about exposing the internal `id` out maybe just the implements direct exposing the internal id(its API designer needs to concern with the id meaning internal id or the API meaning for id, suppose API should be exposed API level meaningful id not internal used id, internal used can present by other keywords)
3. `
slug` may cause API impletments to get more complex
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Smark Meng
OSSEra
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