How do you find your first 100 customers without a marketing budget?

Bootstrapping a B2B SaaS. No budget for ads yet — need to get traction organically. I've tried: - Cold outreach on LinkedIn (low reply rate) - Writing on Medium (tiny audience) - Posting in Reddit (account too new, posts get removed) What actually worked for you in the early days? Looking for tactical advice, not generic 'build something people want' stuff.