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review.firstround.comJan 1, 2026

Mercury's Path to Product-Market Fit - Do the Hard Part First

by First Round Review (featuring Immad Akhund, co-founder and CEO of Mercury)

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TL;DR: Mercury's path challenges common startup wisdom. Akhund argues the idea matters far more than Silicon Valley admits - strong founders can sell anything, which obscures weak PMF (a problem he experienced at Heyzap with 2+ years of pivoting). He spent 4 months having 90 conversations with founders, lawyers, and investors before building. Key insight: spend your time doing the thing you're least capable of proving - for Mercury, that was bank partnerships and compliance, not product building. The MVP had strict non-negotiables: Mercury had to be a company's only account, fully digital, with checks/wires/ACH, multiple owners, and immigrant accessibility. He scrapped the first bank partner after 6 months and redid everything. Despite only 2 of 100 founders being enthusiastic pre-launch, day 4 brought a $1M deposit with zero sales contact. His PMF definition: you wake up with more users and don't know where they came from. Scaling lessons include not copy-pasting advice, recognizing culture as founder personality reflected in company, and the CEO being a 'leveling function' in highs and lows.

Key Insights

  • The idea matters more than Silicon Valley admits - strong founders obscure weak PMF
  • Do the hard part first - the thing you're least capable of proving to the world
  • 'Doable but hard' is the sweet spot for startup ideas
  • Lawyers are surprisingly useful - most do 30-min calls for free
  • PMF definition: you wake up with more users and don't know where they came from
  • Build so well that users are patient with bugs because they're sold on the vision
  • Culture = personality of founders reflected in company
  • CEO is a leveling function - stay even keel in extreme highs and lows

Actionable Takeaways

  • Have 90+ expert conversations (founders, lawyers, investors) before building
  • Identify and tackle the hardest part first - what you're least capable of proving
  • Set strict non-negotiables for your MVP based on what makes it a complete solution
  • Be willing to scrap and rebuild (Mercury scrapped first bank partner after 6 months)
  • Don't rely on pre-launch feedback - only 2 of 100 founders were enthusiastic
  • Give yourself a year after launch before concluding you have (or don't have) PMF
  • Hire for founder-aligned traits - use unconventional methods like hobby presentations
  • Don't copy-paste advice - adapt playbooks to your specific situation

Principles Validated (19)