
Stefan Bader, Cello
From Notion Pages to $2.5M ARR in First SaaS Customers
Stefan Bader is the co-founder and CEO of Cello, an all-in-one referral platform that helps SaaS companies reward their users for bringing in new customers. Back when Stefan was Chief Revenue Officer at a payment processing company, he noticed something odd. His users were bringing in tons of new customers, but there was no way to reward them. Every tool out there was for affiliates and influencers. Stefan saw the opportunity. And in 2022, he quit his job and started Cello. But building it turned out to be way harder than he'd imagined. Paying individual users meant navigating compliance laws in dozens of countries, international banking regulations, and tax requirements that no one had mapped out before. And his MVP was embarrassingly basic. Customers got their analytics through shared Notion pages. No login portal. No dashboard. Just Stefan's team running Python scripts and configuring everything manually behind the scenes. "This is not a product," one early customer told him. But Stefan stayed focused on what mattered - could it actually generate referrals? The answer was yes. He also made pricing dead simple - pay nothing until you make money from referrals. However, most SaaS companies didn't even know they needed this product. Stefan had to educate every prospect about why user referrals were different from affiliate programs, and why they were leaving money on the table. Landing those first SaaS customers required creative tactics - turning pre-seed investors into design partners, collaborating with top content creators like Kyle Poyar, and dogfooding Cello's own referral product. But the real breakthrough came from something tiny - a "powered by Cello" link in their widget. As customers grew, millions of their users saw it. That little link became their biggest growth driver, compounding with every new first SaaS customer they onboarded. Today, Cello generates $2.5M in ARR, powers referral programs for companies like Miro and Typeform, and reaches over 7 million users each month.






















