Viral Loop Designer

Use this skill to design a viral or referral loop for a post-PMF product by extracting the PATTERN (not the tactic) from canonical case studies — Dropbox bilateral-incentive referral, Hotmail email-signature instrumented virality, Airbnb Craigslist cross-posting, LinkedIn public-profile SEO virality — and adapting it to the user's product. Classifies the mechanism type (word-of-mouth amplification, instrumented virality, embedded referral), models K-factor (invitations × conversion rate) and cycle time, and produces a viral-loop-design.md with the loop diagram plus a referral-test-plan.md for experiment execution. Flags the viral spam trap (when sharing becomes annoying and hurts the brand). Triggers when a growth PM asks 'how do I build a referral program like Dropbox?', 'viral loop design', 'how do I make my product viral', 'referral program', 'word of mouth growth', 'K-factor', 'viral coefficient', 'invite mechanism', 'should I offer referral rewards', 'bilateral incentive', 'Hotmail email signature', 'Airbnb Craigslist hack', 'LinkedIn public profiles', or 'viral loop testing'. Also activates for 'our referral program isn't working', 'viral spam trap', or 'refer a friend program design'.

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Install

Claude CodeClawhHubnpxCursorCodexGemini CLI

1. Add marketplace

› /plugin marketplace add bookforge-ai/bookforge-skills

2. Install plugin

› /plugin install hacking-growth@bookforge-skills

3. Use the skill

› /viral-loop-designer

CC-BY-SA · Open sourceGitHub

Source Book

Hacking Growth

Sean Ellis, Morgan Brown

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