Y Combinator has funded over 4,000 startups worth $600B+, and every one of them follows the same core principles. In this video, Arjun Mahadevan, CEO and Founder of doola (a YC-backed startup that’s raised $13M), breaks down the 22 most essential and brutal truths every founder needs to master. From launching before you’re ready to doing things that don’t scale — these aren’t just theories. Arjun shows how doola applies each Y Combinator rule in real life to build, grow, and survive as a startup. If you’re building a startup or dreaming of launching one, this is the YC playbook distilled into real, actionable lessons from a founder who’s living it every day. 00:00 Intro 00:17 Meet the Speaker (Arjun Mahadevan, CEO of doola) 00:40 Launch Now 01:04 Build Something People Want 01:16 Do Things That Don’t Scale 02:16 Find the 90/10 Solution 03:13 Find 10 to 100 Customers Who Love Your Product 03:55 All Startups Are Badly Broken at Some Point 04:51 Write Code, Talk to Users 05:37 It’s Not Your Money 06:17 Growth Is the Result of a Great Product 06:53 Don’t Scale Your Team Until You Have Product-Market Fit 08:11 Valuation ≠ Success 08:42 Avoid Long Negotiated Deals with Big Customers 09:28 Avoid Big Company Corporate Development Inquiries 10:19 Avoid Conferences Unless They Get You Customers 11:08 Pre–Product Market Fit: Stay Small and Nimble 11:51 Startups Can Only Solve One Problem Well 12:35 Founder Relationships Matter More Than You Think 13:08 Sometimes You Need to Fire Customers 13:45 Ignore Your Competitors 14:09 Most Companies Don’t Die Because They Run Out of Money 14:53 Be Nice 15:21 Get Exercise and Sleep 16:02 Final Thoughts --- BUSINESS-IN-A-BOX™ FOR E-COMMERCE: Your entire E-Commerce back office. All in one platform. We handle all the unsexy yet critical back-office tasks, from entity formation and bookkeeping to business analytics and tax filings, so you can focus on growing your dream business. Schedule your demo today! CONNECT W/ ME: - X (Twitter): - LinkedIn: - Instagram: - Instagram: - TikTok: @ ABOUT ME: If you’re new to my channel, my name is Arjun Mahadevan. I’m the founder and CEO of —the Business-in-a-Box™ for E-Commerce. We help entrepreneurs incorporate, get EINs and bank accounts, and handle compliance like bookkeeping and taxes—so they can focus on building. Given this is the internet and anyone can claim anything, I’ll give you some stuff you can google to verify below. How I got here… 21 yrs old: Graduated from the University of Pennsylvania and The Wharton School of Business with a BA in Mathematics and a BS in Economics with a Statistics concentration. 21 yrs old: Landed a job at Dropbox—my "dream job." 24 yrs old: Realized my dream job wasn’t my dream and left. I had the itch to build. 25 yrs old: Started doola to help global founders launch U.S. businesses. 26 yrs old: Went through YCombinator, pitched at demo day, and raised our $3M+ seed round. 27 yrs old: Raised our $8M+ Series A from investors like Nexus Venture Partners, the YCombinator Continuity fund and more. 29 yrs old: Raised a strategic round of $1M+ in funding from HubSpot Ventures and strategic angels like Codie Sanchez and Graham Stephan, 30 years old: Scaled doola into a global business, with customers in over 175 countries and over 10,000 customers served. Today: We’re on a mission to help 1B founders start and scale their dream business. Talent is everywhere, but opportunity is not, and I’m all in on e-commerce, entrepreneurship, and enabling builders. If you’re a founder who wants to spend less time on admin and more time growing your business, we built doola for you. To all the entrepreneurs out there building, I’m rooting for you. Starting an LLC, sending an email, and talking to a stranger are all examples of asymmetric upside, and life is too short not to shoot your shot and do the damn thing. Keep on climbing cringe mountain. Keep on shooting your shot. And ignore the crabs, Arjun