Every resource founders actually use, in one library.

What founders use most, ranked by how many answers lean on it.

1. Most market sizing advice online is generic TAM SAM SOM filler. This one is written by an investor, backed by a survey of 30... Pear VC Essay · ~15 min read · Starting Up Market Sizing Guide Ian Taylor In 13 answers
2. This is the essay that forces the honest question underneath your idea: are you building a growth company or a good small... Paul Graham Essay · ~20 min read · Starting Up Startup = Growth Paul Graham In 13 answers
3. Thiel makes the counterintuitive case that dominating a tiny market first is a feature, not a bug: every lasting monopoly... Penguin Random House India Book · ~224 pages · Starting Up Zero to One: Notes on Startups, or How to Build the Future Peter Thiel with Blake Masters In 13 answers
4. Currier's whole argument is that founder-market fit is more than the one line on a resume that says 'domain expert'. He breaks... NFX Article · ~12 min read · Starting Up The 4 Signs of Founder-Market Fit James Currier In 12 answers
5. Blume's annual report is the single best data-grounded read on what is actually happening in Indian internet and consumption,... Blume Ventures Article · ~180 charts · Starting Up Indus Valley Annual Report 2025 Sajith Pai, Anurag Pagaria and team (Blume Ventures) In 12 answers
6. Most founders treat customer research as a one-time pre-launch exercise, then go quiet once the product ships. Torres makes the... Amazon Book · ~200 pages · Starting Up Continuous Discovery Habits: Discover Products that Create Customer Value and Business Value Teresa Torres In 12 answers
7. This is the most concrete walkthrough of how to test a niche when you have nothing built yet: put up a page describing the... kromatic.com Essay · ~15 min read · Starting Up Fake Door / Smoke Test Kromatic (The Real Startup Book) In 12 answers
8. Blomfield (founder of Monzo and GoCarchless, now a YC partner) gives the concrete mechanics of closing that first B2B deal:... Y Combinator Startup Library Article · 25 min read · Starting Up The Sales Playbook for Founders Tom Blomfield In 12 answers
9. The two ways to fake a product while you test real demand. Do the work by hand in the open (concierge), or hide the manual work... LogRocket Article · ~12 min read · Starting Up Concierge vs. Wizard of Oz MVP LogRocket In 12 answers
10. To say no to the right requests you need feedback you can trust, and this shows how to get it by watching customers rather than... First Round Review Article · 12 min read · Starting Up Get in the Van and Other Tips for Getting Meaningful Customer Feedback Michael Sippey In 12 answers
11. Lenny interviewed founders of Gong, Notion, Figma, Amplitude, Retool and more to trace where their idea actually came from. The... Lenny's Newsletter Article · About 15 min read · Starting Up How the Most Successful B2B Startups Came Up With Their Original Idea Lenny Rachitsky In 12 answers
12. The mutual fund industry body investor corner: fund basics, NAVs, and how SIPs work, straight from the source. AMFI Guide · Wealth AMFI: mutual fund investor resources AMFI In 12 answers
13. A short, pointed essay on why the best ideas grow organically out of the founder's own life and knowledge, the essence of... paulgraham.com Article · ~5 min read · Starting Up Organic Startup Ideas Paul Graham In 11 answers
14. The foundational text of customer development, 'get out of the building' started here and became the backbone of the Lean... steveblank.com Book · ~370 pages · Starting Up The Four Steps to the Epiphany: Successful Strategies for Products that Win Steve Blank In 11 answers
15. Design tactics written specifically for developers and non-designers who need to ship good-looking UI without a design... refactoringui.com Book · ~250 pages · Starting Up Refactoring UI Adam Wathan & Steve Schoger In 11 answers
16. The research-backed classic on consultative selling, the antidote to 'pushy salesperson' instincts. Its... McGraw-Hill Book · book (~200 pages) · Starting Up SPIN Selling Neil Rackham In 11 answers
17. Battle-tested YC advice on landing your critical first engineering hire, from founders who've done it at scale. It reframes... YC Startup Library Article · Essay · Starting Up How to hire your first engineer (YC Startup Library) Y Combinator (Greg Brockman, Harj Taggar) In 11 answers
18. The essay that explains why one badly-placed meeting can destroy a founder's entire day of building, and what to do about it.... paulgraham.com Article · short · Starting Up Maker's Schedule, Manager's Schedule Paul Graham In 11 answers
19. This is the founder essay that made the case for validating before you build, from the person who did it with Buffer. Gascoigne... Medium (Joel Gascoigne, co-founder of Buffer) Essay · Starting Up How to successfully validate your idea with a Landing Page MVP Joel Gascoigne In 11 answers
20. Most first 100 users advice is vague. This piece is the opposite: it groups the real cold start tactics into seven concrete... Lenny's Newsletter Article · About a 15 minute read · Starting Up How the biggest consumer apps got their first 1,000 users Lenny Rachitsky In 11 answers
21. If you are selling to companies rather than consumers, this is the specific playbook. Four concrete ways founders got signal... Lenny's Newsletter Article · ~12 min read · Starting Up How to Validate Your B2B Startup Idea Lenny Rachitsky In 11 answers
22. Once you are testing an idea, this piece gives you concrete signals that tell you whether it is actually working, from... Lenny's Newsletter Article · about 15 min read · Starting Up How to Know If You've Got Product-Market Fit Lenny Rachitsky In 11 answers
23. A rare account of the specific moments a GTM changed shape, from narrowing to cold email agencies, to reversing the demo, to... First Round Review Article · ~25 min read · GTM The GTM Inflection Points That Powered Clay to a $1B+ Valuation Varun Anand In 11 answers
24. Benchmarks from 500 plus products: 34 percent average, 36 percent for SaaS. If you have ever wondered whether your number is... Lenny's Newsletter Article · 12 min read · GTM What is a good activation rate Lenny Rachitsky and Yuriy Timen In 11 answers

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