Particle
Justin Arn is a seasoned professional with a diverse background in product management and marketing. Currently serving as Co-Founder at Particle since January 2024, Justin focuses on empowering marketing and product teams to enhance their efficiency and effectiveness. Previously, as a Senior Product Manager at Medium from February 2020 to February 2025, Justin led the Membership Team and implemented product-led growth strategies that tripled monthly new memberships. Justin's experience also includes roles at WeWork, Flatiron School, New York University, and the Gyeonggi Provincial Government, where responsibilities ranged from launching new products to developing online course offerings. Justin holds an MBA from NYU Stern School of Business, specializing in Product Management, Marketing, and Leadership.
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Particle
At Particle, we help marketing and product teams grow smarter and execute faster—without wasted time, budget, or stress. Our Services: 🚀 Coaching – We work 1:1 with marketing and product teams to sharpen their skills, solve problems faster, and execute with confidence—so leaders can focus on strategy, not hand-holding. 💡 Strategy Development – We design data-driven strategies that address your toughest growth challenges, empower smarter decision-making, and drive alignment across teams for long-term success. ⚡ Tactical Execution – When you know what needs to be done but lack the internal resources, we step in to execute high-impact growth initiatives—so you can move faster and get results. More progress. Fewer roadblocks. Smarter growth. Let’s talk.