To connect your tastytrade account to Option Alpha, go to Settings --> Trading Accounts and click 'Authorize on tastytrade.com.'
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Log in using your tastytrade username and password to authorize your account.
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Once your accounts are connected you can select your tastytrade account when creating a new bot to send live orders to the broker for execution.
You can authorize one set of credentials (username/password) per broker. You can connect multiple accounts with the same username.