saas.unbound is a podcast for and about founders who are working on scaling inspiring products that people love, brought to you by https://saas.group/, a serial acquirer of B2B SaaS companies.

In episode #10 of season 6, Anna Nadeina talks with Sergiy Korolov, co-founder of Railsware and the brain behind Mailtrap.

From accidentally launching one of the most popular developer tools with zero marketing budget, to running the company with an all-engineer team — Sergiy's journey is packed with lessons most founders learn the hard way.

In this episode:

→ How Mailtrap grew to hundreds of thousands of users before charging a cent

→ The "product studio" model Railsware uses to co-found new companies

→ Why bootstrapping forces better decisions than VC money

→ The hard truth about vibe coding and AI's real impact on engineering teams

→ How to hire when you don't know enough to assess the role

→ Why your biggest job as CEO is to stop having sleepless nights

----------- Episode's Chapters -----------

0:05 — Introduction & Product Overview

0:27 — Background & Early Days of Railsware

3:51 — Building Product Studio Culture

6:58 — Creating Mailtrap - From Tool to Platform