https://crypto-prices.fly.dev/
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Shows prices in real-time for Bitcoin, Ethereum and Dogecoin.
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Allows logged in user to favorite a crypto.
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Shows how many people in total have favorited a crypto, in real-time.
asdf install
mix setup
iex -S mix phx.server
The approach for "favorite totals" is not straightforward. To avoid doing a "count" in the database on every change, we only send increment/decrement (+/- 1) deltas to the LiveView processes. As such, lost messages will result in incorrect totals being displayed, even if future correct messages are received.