Meta Tech Podcast

84: Trust But Canary: Configuration Safety at Scale

Have you ever wondered how Meta makes config rollouts safe at scale? In this episode, Pascal sits down with Ishwari and Joe to discuss Meta's approach for propagating changes across services in seconds and discuss why speed increases the need for strong safeguards. Catch the episode to discover canarying and progressive rollouts, the health checks and monitoring signals used to catch regressions early, and how incident reviews focus on improving systems rather than blaming people. We also hear how data and early AI/ML are slashing alert noise and speeding up bisecting when something goes wrong. Got feedback? Send it to us on Threads (https://threads.net/@metatechpod), Instagram (https://instagram.com/metatechpod) and don't forget to follow our host Pascal (https://mastodon.social/@passy, https://threads.net/@passy_). Fancy working with us? Check out https://www.metacareers.com/.   Links FFmpeg at Meta: Media Processing at Scale - https://engineering.fb.com/2026/03/02/video-engineering/ffmpeg-at-meta-media-processing-at-scale/ Reliably Changing Configuration @ Scale - https://atscaleconference.com/reliably-changing-configuration-scale/  Timestamps Intro 0:06 Introduction and Overview of Configuration Changes 2:31 Understanding Configurations in Distributed Systems 4:02 Meta's Configuration Management Systems 6:43 Safeguards and Incident Prevention 9:22 Deployment Mechanisms: Canary and Progressive Rollouts 12:06 Challenges in Configuration Consumption 14:39 Health Checks and Incident Response 17:13 Mitigation Strategies for Configuration Issues 19:18 Balancing Developer Velocity and Configuration Safety 21:09 Data-Driven Improvements in Incident Management 22:12 Leveraging AI for Change Detection 26:05 Challenges in Deployment and Testing 28:21 Reinventing Change Safety Strategies 30:24 War Stories: Learning from Past Incidents 32:59 Outro 36:10

83: Patch Me If You Can: AI Codemods for Secure-by-Default Android Apps

At Meta, even seemingly simple engineering tasks—like updating an API—become monumental undertakings when you're dealing with millions of lines of code and thousands of engineers, especially if the changes are security-related. In today's episode, Pascal talks to Alex and Tanu about the challenges and learnings from the journey of making Meta's mobile frameworks more secure at a scale few companies ever experience. Tune in to this episode and join us as we explore the compelling crossroads of security, automation, and AI within mobile development. Got feedback? Send it to us on Threads (https://threads.net/@metatechpod), Instagram (https://instagram.com/metatechpod) and don't forget to follow our host Pascal (https://mastodon.social/@passy, https://threads.net/@passy_). Fancy working with us? Check out https://www.metacareers.com/. Links How AI Is Transforming the Adoption of Secure-by-Default Mobile Frameworks - https://engineering.fb.com/2025/12/15/android/how-ai-transforming-secure-by-default-mobile-frameworks-adoption/  RCCLX: Innovating GPU Communications on AMD Platforms - https://engineering.fb.com/2026/02/24/data-center-engineering/rrcclx-innovating-gpu-communications-amd-platforms-meta/  The Death of Traditional Testing: Agentic Development Broke a 50-Year-Old Field, JiTTesting Can Revive It - https://engineering.fb.com/2026/02/11/developer-tools/the-death-of-traditional-testing-agentic-development-jit-testing-revival/  Timestamps Intro & News 0:06 Meet the Product Security Team 2:07 Understanding the Intent System 4:13 Security Challenges in Android's Intent System 6:44 Proposed Solutions for Intent Security 9:39 Meta's Unique Challenges at Scale 12:34 Implementing a Secure Link Launcher Framework 15:32 Leveraging AI for Contextual Understanding 17:55 Navigating AI-Driven Code Modifications 20:47 Developer Experience with AI Code Mods 21:49 Validation Challenges in AI Code Generation 25:37 Evolution of AI in Code Modifications 29:29 Identifying AI's Strengths in Security 36:20 Future Directions in AI and Framework Development 42:58 Outro 46:58  

82: CSS at Scale with StyleX

It's not just Not Invented Here Syndrome. Some technologies like CSS simply don't scale if you're building some of the largest websites on the planet with thousands of engineers committing to the same code base every day. StyleX is Meta's open-source solution for CSS at scale and allows atomic styling of components while deduplicating definitions for bundle size and exposing a delightfully simple API for developers.  Tune in to learn from Melissa, one of the StyleX maintainers how Open Source has acted as a force multiplier for the project, how interacting with other large companies adopting StyleX has been, and much more! Got feedback? Send it to us on Threads (https://threads.net/@metatechpod), Instagram (https://instagram.com/metatechpod) and don't forget to follow our host Pascal (https://mastodon.social/@passy, https://threads.net/@passy_). Fancy working with us? Check out https://www.metacareers.com/. Links How AI Is Transforming the Adoption of Secure-by-Default Mobile Frameworks: https://engineering.fb.com/2025/12/15/android/how-ai-transforming-secure-by-default-mobile-frameworks-adoption/  StyleX: https://stylexjs.com MTP 67: Measuring Developer Productivity with Diff Authoring Time: https://pca.st/pt4p4tv5  Timestamps Intro and news 0:06 Introduction Melissa 1:47 Why did we build our own styling system? 4:07 StyleX API 5:36 cx vs StyleX 7:37 Component styling and priorities 10:38 How StyleX evolved in the past seven years 15:20 Community influence 19:33 Open Source 24:07 Challenges of OSS 27:02 Managed breaking changes in OSS 29:48 Measuring success for StyleX 32:04 Packaging challenges 34:34 StyleX competition 38:42 Creating the StyleX roadmap 40:24 Outro 43:15

81: From Zero to Polish: Building Meta Ray-Ban Display

You've likely heard of the Meta Ray-Ban Display by now — but what's it actually like to work on it? In this episode, Pascal talks to Kenan and Emanuel about the exciting features of Meta's First-Gen Display Glasses and Neural Wristband, the engineering and product challenges they encountered during development, and their vision for future generations of these devices.  Got feedback? Send it to us on Threads (https://threads.net/@metatechpod), Instagram (https://instagram.com/metatechpod) and don't forget to follow our host Pascal (https://mastodon.social/@passy, https://threads.net/@passy_). Fancy working with us? Check out https://www.metacareers.com/. Links Pyrefly Beta: https://pyrefly.org/blog/pyrefly-beta/ Pyrefly and Pydantic: https://pyrefly.org/blog/pyrefly-pydantic/  Meta Ray-Ban Display: https://www.meta.com/gb/ai-glasses/meta-ray-ban-display/  Timestamps Intro 0:06 Introduction Kenan 1:35 Introduction Emanuel 5:03 Roles and responsibilities 8:07 What is Meta Ray-Ban Display? 11:13 Memorable challenges: Clasps 15:52 Memorable challenges: Display 19:24 Celebrating incremental wins 23:51 The feedback cycle in hardware engineering 26:29 Open culture and dogfooding 31:39 One-way doors 32:44 Striving for quality and polish in fast-moving environments 36:25 UI principles for AI glasses 40:15 Future Plans 44:04 Outro 46:53 Blooper 47:49  

80: Lowering emissions with the Open Compute Project

In this episode, Pascal talks to Dharmesh J. (DJ) and Lisa about the vision for the open, scalable future of networking hardware for AI and to break down Meta's big announcements from the 2025 Open Compute Project (OCP) Summit. We dive into the OCP ecosystem, explore how AI is used to enhance our carbon modeling, and share our progress toward achieving Net Zero emissions across all scopes by 2030. Got feedback? Send it to us on Threads (https://threads.net/@metatechpod), Instagram (https://instagram.com/metatechpod) and don't forget to follow our host Pascal (https://mastodon.social/@passy, https://threads.net/@passy_). Fancy working with us? Check out https://www.metacareers.com/. Links OCP: https://www.opencompute.org/ OCP Summit 2025: https://engineering.fb.com/2025/10/13/data-infrastructure/ocp-summit-2025-the-open-future-of-networking-hardware-for-ai/  How Meta Is Leveraging AI To Improve the Quality of Scope 3 Emission Estimates for IT Hardware: https://engineering.fb.com/2025/10/14/data-center-engineering/how-meta-is-leveraging-ai-to-improve-the-quality-of-scope-3-emission-estimates-for-it-hardware/  Timestamps Intro 0:06 Introduction Lisa 1:49 Introduction DJ 3:16 What is OCP? 4:04 OCP's scale 5:24 Open vs closed hardware ecosystems 9:26 Examples of OCP projects 11:33 Sustainability in OCP 14:08 How did you get into OCP? 15:59 Marrying infrastructure growth with sustainability 19:05 Emissions scopes and tracking 25:07 Measuring scope 3 26:06 What components embed the most carbon? 30:47 DFE vs DFS 32:34 Hardware reuse 33:39 Outro 37:48