Hey! I'm a co-founder of Balanced, a payments API that allows for just this type of functionality. We support next-day ACH deposits to bank accounts within the US for 25¢ a transaction.

Here's a sample CURL command (copy/paste to your terminal to test it out):

  curl https://api.balancedpayments.com/v1/credits \
        -u da3da6de7c9311e288c9026ba7f8ec28: \
        -d "amount=10000" \
        -d "bank_account[routing_number]=121000358" \
        -d "bank_account[type]=checking" \
        -d "bank_account[name]=Johann Bernoulli" \
        -d "bank_account[account_number]=9900000001"

Learn more: https://www.balancedpayments.com/#payouts