At Veryable, we were fortunate enough to participate in a case study with Plaid & Dwolla, two third party partners we use (and love) at the company. Plaid & Dwolla power our onboarding and payout systems for our operators (workers), and do a fantastic job doing so. Plaid also recently was acquired by Visa, Kudos for them!
https://blog.plaid.com/dwolla/
Link to case study: