The CTO Podcast with Fexingo: Technical Leadership, Architecture, and Engineering Org

Episode 4 of The CTO Podcast with Fexingo dives into Stripe's 2024-2025 migration of its core payments processing system from a monolithic Ruby-on-Rails architecture to a Rust-based, event-driven platform. We explore the technical tradeoffs Stripe's engineering team faced, including how they managed the migration of over 100 million API requests per day without downtime. Lucas and Luna break down...

Episode 3 of The CTO Podcast dives into how Monzo, the UK neobank, rebuilt its core transaction-processing engine after hitting performance and reliability ceilings. Lucas and Luna walk through the specific architectural problem: a relational database bottleneck that capped transaction throughput at 1,000 per second during peak hours. They explain Monzo's decision to move to a custom event-sourcin...

In this episode, Lucas and Luna examine Spotify's famous 'Squad' model—the engineering org structure that inspired a thousand startups—and why the company itself has been quietly moving away from it since 2023. They trace the tension between autonomy and alignment, the rise of 'Guilds' as a coordination layer, and what happens when a hyper-growth org outgrows its own playbook. If you've ever wonde...

In this debut episode of The CTO Podcast, Lucas and Luna unpack a single engineering decision at DoorDash that nearly broke the platform then saved it. They trace how a change from synchronous to asynchronous dispatch in 2019 cut delivery times by 12 percent but also triggered a cascade of system failures that forced a complete architecture rethink. Through this one case, they establish the show's...