I worked with Flowium on a Mailchimp to Klaviyo migration. Andriy is very methodical and good at what he does. He lays out a plan and sticks to it, but most importantly he makes you stick to the plan as well. He will push a project forward even if the going gets tough and he does not give up. Andriy was always willing to get on a call and talk things through and he is concerned with making sure that you feel good about where the project is and if you’re not, he’ll fix it. I highly recommend Andriy.