In this episode, Barnaby Clark, CEO of Line-Up, reveals the engineering practices behind resilient ticketing systems that handle real-world demand. Barnaby explains how Line-Up rebuilt their platform from the ground up to meet the complex needs of live events, from unique inventory structures and API scaling to predictive load handling and third-party integrations. Barnaby dives into the evolving threat of bots, the nuances of asynchronous payments, and how to design for bursts in traffic without breaking the customer experience. It’s a practical look at infrastructure, performance, and the unpredictable nature of ticketing at scale.

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Barnaby Clark is CEO and Co-Founder at Line-Up. He has 12 years of experience designing innovative software products across diverse stacks, scaling and guiding cross-functional teams, building high-growth e-commerce platforms, and overcoming complex software challenges. Line-Up was shortlisted for Best Technology Provider at the British Media Awards, won Seedcamp London and has secured multiple funding rounds from angel investors, institutional backers, and corporate entities. Prior to Line-Up, Barnaby spent 5 years working on Mergers & Acquisitions and private capital fundraising efforts within the technology sector.

This podcast is hosted by José Quaresma, researched by Joseph Thwaites and produced by Perseu Mandillo.

• (00:00) - Introduction: Designing Scalable Ticketing Systems
• (00:45) - Barnaby’s Journey to Founding Line-Up
• (02:15) - Unique Scaling Challenges in Ticket Sales
• (05:08) - Breaking Down the Ticket Purchase Journey
• (06:41) - Read vs. Write Operations in Scalability
• (09:53) - Handling Sudden Traffic Spikes
• (12:11) - Predictive Scaling and Early User Signals
• (17:26) - Integrating Third-Party Ticket Sales APIs
• (20:02) - Payment Providers and Asynchronous Challenges
• (26:09) - Disaster Recovery and System Protection
• (30:35) - Tackling Bots and Fraud in Ticketing
• (35:04) - Rapid-Fire Insights & Recommendations