
saas.unbound How to build a dev tool with zero marketing with Sergiy Korolov @Mailtrap
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
14:10 — Developing Product Taste & Skills Matrix
19:25 — Hiring Strategy & Team Building
27:22 — Dogfooding & Product Development Process
35:24 — AI Integration in Products & Engineering
44:16 — Wins, Lessons & The Calendly Story
48:26 — Founder Hacks & Work-Life Balance
Sergiy - https://www.linkedin.com/in/sergiykorolov/
Railaware - https://railsware.com/
Mailtrap - https://mailtrap.io/
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