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Kevin Xu, perhaps better known by his Reddit moniker - Sir Jack, built an $8M fortune trading stocks on Reddit’s WallStreetBets before leaving his day job at YouTube to build AfterHour, a stock market super app. It raised $4.5M in it’s seed round last year.

Some takeaways:

🎯 Community Building 101:

* Go where your audience already is - Kevin saw 10x better results from engaging on Reddit vs traditional media like Fox Business or documentaries

* Authenticity trumps strategy - Kevin's SirJack persona succeeded because it wasn't originally meant to be anything, just genuine trading updates

* Communities need a clear reason to exist beyond just "having a community" - for AfterHour, it's helping people make money together

💡 Growth in 2025:

* Product differentiation is crucial - Kevin identified a key gap in finance platforms around trust and verification of trades

* Three viable paths to growth: novelty (viral AI features), authenticity (genuine creator connections), or enabling creators to monetize

* Mobile-first matters - Kevin intentionally built AfterHour as a "bathroom app" to capture daily habits and leverage push notifications

🎨 Design Philosophy:

* Ruthlessly eliminate complexity - AfterHour limits screens to 2 main buttons max

* Only show what matters most - resist the urge to display every possible metric just because you can

* Design for the average user, not power users - most people don't need every feature from Yahoo Finance

🚀 Platform Building:

* Communities need to evolve into "communities of communities" to achieve long-term sustainability

* Focus on unique value-add vs replicating existing tools - AfterHour emphasizes social features over duplicating stock data available elsewhere

* Trust and verification are crucial - Kevin built features to verify trades because screenshots alone weren't enough

🔑 Key Leadership Insight:

* Different phases need different skills - early stage (0-0.1) requires hands-on community building and DMing users individually, while scaling requires shifting focus to product and broader marketing initiatives

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Where to find Kevin Xu:

* Website: https://afterhour.com/

* LinkedIn: https://www.linkedin.com/in/imkevinxu/

* X: https://x.com/imkevinxu

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In this episode, we cover:

00:00 From Reddit Fame to Startup Success 01:29 The Journey of Entrepreneurship 04:20 The Rise of Wall Street Bets 06:23 Building a Community in Finance 09:34 The Transition from Anonymity to Identity 12:28 Creating a Financial Super App 15:14 Navigating Fame and Community Engagement 17:37 The Role of Authenticity in Community Building 20:42 Balancing Personal Brand and Business Goals 23:11 The Impact of Media on Business Growth 32:02 Building Community on Reddit 35:42 Onboarding and User Experience 37:20 Marketing Strategies on Reddit 39:34 The Role of Community in Marketing 41:24 Control Over Algorithms and Content 42:56 Algorithm Development for Diverse Users 43:45 Community Building Strategies 47:00 Sustaining Community Longevity 47:58 Mobile-Only Strategy 50:09 Design Principles for User Engagement 54:42 Leveraging AI in Development 57:38 Essentials for Building a Community 01:01:38 The Future of AfterHour and Community Dynamics

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Obligatory disclaimer: I've worked at YouTube and Google for about a decade in various marketing teams. Nothing I say in my personal spaces is necessarily endorsed by them.

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