Hi Deriv Community Members,
Named after the popular 18th-century French roulette theorist, Jean le Rond d’Alembert, this strategy encourages traders to increase contract size after a loss and decrease it after a successful trade.
The d'Alembert system is a strategy where you increase or decrease the size of your stake by one unit each time you lose or win respectively.If you lose, you increase your stake by one unit.
If you win, you decrease your stake by one unit (Use the same term as displayed on our page to avoid confusion)
To use this strategy on your Bot, go to the “Bot builder” and click "Quick strategy” 
Select D’Alembert strategy
You may edit the parameters accordingly and click “Edit” to further check on the strategy. Otherwise, you may click “Run” to automate your trades.
To know more about quick strategy, please refer to this topic: Simple Steps in Setting Up Quick Strategy in Dbot
If you have any questions, please visit our Help Centre or contact us via Live Chat and WhatsApp.