Micro Frontends at Scale with Luca Mezzalira (O’Reilly Author and Principal Architect at AWS)

Description

In this episode of Señors @ Scale, Dan sits down with Luca Mezzalira, Principal Serverless Specialist at AWS and author of Building Micro-Frontends, for a deep and highly practical look at scaling frontend architectures for hundreds of developers. Luca shares the real story behind how micro-frontends were born — from his early experiments at DAZN trying to scale a live sports platform across 40 devices and 500+ engineers, to pioneering techniques that cut app startup times from 40 seconds to 12. We break down how distributed frontends actually work: How to design stable application shells with zero global state, How to compose independently deployed views without iframes, and how guardrails like bundle-size budgets and canary deployments keep massive systems fast and safe. Luca also explains the hidden challenges most teams miss — governance, team topology, and socio-technical design. He shows how to evolve from a monolith to micro-frontends step by step, using edge routing, feature flags, and domain-driven design to scale safely without rewrites. The conversation goes beyond theory — into the mechanics of migration, platform teams, CI/CD pipelines, and why friction in your system is actually a signal, not a failure. If you’re leading a frontend platform, planning a migration, or just trying to make sense of where micro-frontends actually fit, this episode is a masterclass in autonomy, architecture, and evolution at scale. Chapters 00:00 The Origin of Micro-Frontends at DAZN 05:41 Building a Distributed Frontend Without iFrames 08:50 Designing the Application Shell and Stateless Architecture 12:23 Zero Global State and Memory Management 15:53 Guardrails for Bundle Size and Developer Discipline 17:39 Governance and Designing for Scale 20:18 When (and When Not) to Adopt Micro-Frontends 22:46 Canary Releases and Edge Routing for Safe Migration 25:49 Vertical vs Horizontal Splits in Micro-Frontends 31:30 Lessons from Building the First Edition of the Book 35:38 Frameworks, Federation, and Modern Tools 39:22 Core Principles of Successful Frontend Architecture 42:06 Building Platform Teams and Core Governance 44:19 When Micro-Frontends Don’t Make Sense 47:50 Micro-Frontends for Small Teams and Startups 49:32 Monorepo vs Polyrepo – What Actually Matters 53:10 Preventing Duplication and Encouraging Communication 57:39 Why a Design System Is Non-Negotiable 59:17 Common Anti-Patterns in Micro-Frontend Architecture 1:03:33 Book Recommendations and Final Thoughts Follow & Subscribe: 📸 Instagram: https://www.instagram.com/senorsatscale/ 📸 Instagram: https://www.instagram.com/neciudev 🎙 Podcast URL: https://neciudan.dev/senors-at-scale 📬 Newsletter: https://neciudan.dev/subscribe 💼 LinkedIn: https://www.linkedin.com/in/neciudan 💼 LinkedIn: https://www.linkedin.com/company/se%C3%B1ors-scale/ Additional Resources 📘 Building Micro-Frontends – Luca Mezzalira (O’Reilly) buildingmicrofrontends.com 🌐 buildingmfe.com 💬 Luca’s Blog: https://lucamezzalira.com #microfrontends #aws #frontendarchitecture #javascript #webdevelopment #softwareengineering #softwarearchitecture #react #scaling #teamtopologies #serverless #señorsatscale Don’t forget to like, comment, and subscribe for more engineering stories from the front lines. How is your team approaching frontend scaling and independence? Share below 👇