Meta Tech Podcast

Confused by the syntax of git’s rebase command? Overwhelmed with branch management? Check out Meta’s new git-compatible source control management system Sapling. Durham and Michael, two of the architects behind the recent open-source release, join Pascal on the podcast to discuss their plans for the project, how it was possible to extract one small part of Meta’s large SCM codebase and what the differences between Sapling, git and Mercurial are. Got feedback? Send it to us on Twitter (https://twitter.com/metatechpod), Instagram (https://instagram.com/metatechpod) and don’t forget to follow our host @passy (https://twitter.com/passy and https://mastodon.social/@passy). Fancy working with us? Check out https://www.metacareers.com/. Links: Sapling: https://sapling-scm.com/ Review Stack: https://reviewstack.dev/ Timestamps: Intro 0:06 Durham and Michael Intro 1:18 What is Sapling? 2:56 git Compatibility 3:48 What's Available Today? 5:28 Sapling vs git 7:28 Branching Models 10:20 Stacks 13:09 Stacks and GitHub 17:28 Scaling Sapling 22:25 Extracting Sapling for Open Source 29:32 What's Next for Sapling 34:22 Outro 39:07 Bloopers 40:00

It’s the most wonderful time of the year: The time to talk about calling libraries that power most of our audio and video calls across Meta’s app. Alice, Ishan and Hani join Pascal to talk about how they replaced the different calling solutions with a library that’s extensible by the teams that choose to adopt it. But with great power comes great responsibility, so how does their team balance the desire for new features with the mandate to stay small, fast and reliable? Tune in for episode 46 to learn this and more! Got feedback? Send it to us on Twitter (https://twitter.com/metatechpod), Instagram (https://instagram.com/metatechpod) and don’t forget to follow our host @passy (https://twitter.com/passy and https://mastodon.social/passy). Fancy working with us? Check out https://www.metacareers.com/. Links: Rsys: A smaller, faster video calling library for our apps: https://engineering.fb.com/2020/12/21/video-engineering/rsys/ Flipper: https://fbflipper.com/ Horizon Workrooms: https://www.meta.com/de/en/work/workrooms/ Timestamps: Intro 0:06 Team Overview 1:34 RSYS History 4:42 Design Tradeoffs 6:10 Testing Infrastructure 8:09 Usage and Support Model 11:04 Core Architectural Components 12:58 Changing Engines Mid-Air 16:48 Measuring Quality 19:30 Building on top of RSYS 21:34 Collaboration Model 24:22 Feature Development 26:41 Experimentation 28:43 Metaverse Strategy 29:51 What's Next for RSYS 33:26 Outro 34:36 Bloopers 35:24

Back from a short hiatus, Pascal is joined by Jon to talk about the infrastructure that allows commit to sync between Meta's monorepo and GitHub. While ShipIt has been around for a while, allowing commits from the internal repository to sync out to GitHub, Diff Train is its younger brother to allow the inverse. This makes it possible for open-source-first projects like PyTorch to develop on GitHub and bring changes back into the monorepo without sacrificing security and reliability. Got feedback? Send it to us on Twitter (https://twitter.com/metatechpod), Instagram (https://instagram.com/metatechpod) and don’t forget to follow our host @passy (https://twitter.com/passy). Fancy working with us? Check out https://www.metacareers.com/. Links: https://github.com/facebook/pyre-check https://github.com/facebookincubator/cinder https://github.com/facebook/hhvm https://github.com/facebook/fbshipit Timestamps: Intro 0:06 Intro Jon 1:49 Open-sourcing an internal project 7:26 Open Source Team @ Meta 10:22 Third-party dependencies 12:07 ShipIt 13:48 Diff Train 29:01 Most excited about 41:07 The GIL 42:29 Outro 44:22

Ever wondered how the culture of big companies like Meta, Microsoft and Amazon differ? Jay comes with a fairly unique perspective as he has now worked at all three of them. In his discussion with Pascal, he shares his views on the trade-offs that a company value like “Move Fast” brings along and how companies assign different weights to the value of making mistakes. Got feedback? Send it to us on Twitter (https://twitter.com/metatechpod), Instagram (https://instagram.com/metatechpod) and don’t forget to follow our host @passy (https://twitter.com/passy). Fancy working with us? Check out https://www.metacareers.com/. Links: Power On: The Story of Xbox: https://www.youtube.com/watch?v=AJYsA1jXf60 Timestamps: Intro 0:06 Jay Introduction 1:18 Business Engineering at Meta 2:43 Social Impact 5:35 Culture Shocks 8:24 The Value of Mistakes 14:15 Finding your Pace 16:14 Modes of Working in Different Teams 19:32 Expectations vs Reality 23:36 Workflows 30:02 Incidents 37:26 Internal Mobility 42:24 Outro 45:30 Bloopers 46:10

msys is the technology that underpins most of the messaging products Meta offers. What started as a small library in C wrapping sqlite is now used by many teams across the company and is now trying to address the developer experiences challenges that arise from the initial focus on speed and size above all else. Tune in to Pascal's interview to learn how Akshay and Chris are tackling this and other thorny issues.  Got feedback? Send it to us on Twitter (https://twitter.com/metatechpod), Instagram (https://instagram.com/metatechpod) and don’t forget to follow our host @passy (https://twitter.com/passy). Fancy working with us? Check out https://www.metacareers.com/. Links: Meta Tech Podcast Episode 37: Faster and Smaller Messenger for With Amy Meta Tech Podcast Episode 39: White Labeling Messenger for iOS with Amy Project LightSpeed: Rewriting the Messenger codebase for a faster, smaller, and simpler messaging app   Timestamps:   Intro 0:06 Introduction Chris 1:33 Introduction Akshay 2:54 msys overview 3:37 Products adopting msys 7:16 Building features with msys 13:06 Migrations 20:28 Optimising DevX 26:38 Web Client 33:30 What's Next for msys 34:40 Outro 36:50 Outtakes 37:45

Cami returns to the Meta Tech Podcast, with now having 18 months of AR/VR experience under her belt. Cami is excited to share what developers can now do on the Quest platform. In this episode, Pascal and Cami discuss new SDKs for motion controls, voice and spatial objects; and for creators without programming experience - there’s Horizon Worlds.  Cami, as a Developer Advocate, shares her expertise whilst being acutely aware of areas that require careful consideration. To find out more from Cami and the exciting updates on Quest, tune into episode 43 of the Meta Tech Podcast. Got feedback? Send it to us on Twitter (https://twitter.com/metatechpod), Instagram (https://instagram.com/metatechpod) and don’t forget to follow our host @passy (https://twitter.com/passy). Fancy working with us? Check out https://www.metacareers.com/.   Links: Display prototypes on Zuck’s Facebook: https://www.facebook.com/4/videos/355247026677540/ Boz to the Future on Display Tech: https://www.facebook.com/1681/videos/390455039578133/ Presence Platform Announcement: https://developer.oculus.com/blog/introducing-presence-platform-unleashing-mixed-reality-and-natural-interaction-for-oculus-developers/?locale=en_GB Presence Platform Developer Portal: https://developer.oculus.com/presence-platform/ Cami on Twitter: https://twitter.com/cwillycs Keep talking and nobody explodes: https://www.oculus.com/experiences/quest/2010043642376517/?locale=en_GB wit.ai: https://wit.ai/   Timestamps: Intro 0:06 Cami: Reintro 2:01 Horizon Worlds 3:22 Presence Platform SDK 7:59 Voice SDK 12:57 Insights SDK 17:34 Next-Gen Displays 24:14 Keep Talking and Nobody Explodes 28:20 Building for Horizon 31:37 ELI5 on YouTube 36:59 Meta Connect 42:51 Outro 44:14

The approach we take to building the Facebook app is based around three adjectives: trustworthy, people-centric and unified. In this episode, Pascal talks with Maria who is a director of engineering for product architecture and product excellence. They discuss what it means for a culture that is known for being driven by metrics to become more people-centric. What are examples of metrics that are aligned with people goals and when do they fail to capture them? Tune in to hear the answers to these questions and much more. Got feedback? Send it to us on Twitter (https://twitter.com/metatechpod), Instagram (https://instagram.com/metatechpod) and don’t forget to follow our host @passy (https://twitter.com/passy). Fancy working with us? Check out https://www.metacareers.com/. Links: Rachel Nabors on The Diff: https://thediffpodcast.com/docs/episode-12 Meet the Developers: Mobile Edition (Pritesh Nandgaonkar): https://developers.facebook.com/blog/post/2022/05/23/meet-the-developers-pritesh-nandgaonkar/ Meta Open Source on YouTube: https://www.youtube.com/c/FacebookOpenSource Meta Tech Podcast Episode 29: Design Systems with Sriram: https://pca.st/u8r4u6h6 Meta Tech Podcast Episode 9: Android Bytecode Optimisation with Emma https://pca.st/J3cn    Timestamps: Intro 0:06 The Diff: Episode 12 1:23 Meet The Developer: Prish 1:38 Meta Open Source on YouTube 2:01 Intro 2:26 Intro Maria 2:36 Craft in FB App 5:15 Metrics vs People? 6:40 Unquantifiable Quality Goals 10:14 Dropping Facial Recognition 11:38 Dynamic Goals in a Dynamic World 13:21 Driving Cultural Change 15:49 Average vs Power Users 18:53 Metrics for Quality 22:33 Dev Tools' Role for Quality 29:12 Supporting People at Meta 33:38 Most Exciting Upcoming Change 39:25 Outro 40:43 Bloopers 42:00

For our second special for Earth Week, we are talking to Bilge who works as a research scientist at Meta AI. Her open-source project Carbon Explorer evaluates solutions to make data centres operate on 24/7 renewable energy. Why this is easier said than done and how engineers can help within their day-to-day work to reduce their carbon footprint are among the many things Pascal and Bilge discuss in this episode.   Got feedback? Send it to us on Twitter (https://twitter.com/metatechpod), Instagram (https://instagram.com/metatechpod) and don’t forget to follow our host @passy (https://twitter.com/passy). Fancy working with us? Check out https://www.metacareers.com/. Links: Carbon Explorer: https://github.com/facebookresearch/CarbonExplorer Holistic Approach for Designing Carbon Aware Datacenters: https://arxiv.org/abs/2201.10036 Open Catalyst: https://opencatalystproject.org/ Open Catalyst SchrepTech Interview: https://ai.facebook.com/blog/how-ai-is-helping-address-the-climate-crisis/ Timestamps: Intro 0:05 Intro Bilge 2:18 Optimising for the Environment 4:01 Carbon Explorer 5:02 Mitigations for Renewable Intermittency 7:17 Operational and Embodied Footprints 10:57 Motivations for Carbon Explorer 13:06 Battery Storage 14:36 Renewable Curtailment 15:52 Empowering Engineers 18:20 Carbon Intensity APIs 19:22 AI Carbon Intensity Forecasts 22:07 Carbon Metrics 23:17 Where to Learn More 25:38 Outro 27:32 Bloopers 29:45

The most recent IPCC report has reiterated that the climate crisis is an all hands on deck situation. We all need to think about the impact our actions have on the planet that provides our life support system. Ramya is a TPM on the Meta AI team and analyses the impact AI has, as it grows superlinearly, on energy use and carbon emissions. Her recent work on Green AI identifies ways for reducing that footprint without limiting the options engineers have for building great products for connecting people. Got feedback? Send it to us on Twitter (https://twitter.com/metatechpod), Instagram (https://instagram.com/metatechpod) and don’t forget to follow our host @passy (https://twitter.com/passy). Fancy working with us? Check out https://www.metacareers.com/.   Acronyms: LCA: Life Cycle Assessment PUE: Power Usage Efficiency Links: Sustainable AI: Environmental Implications, Challenges and Opportunities: https://arxiv.org/abs/2111.00364 Make an Impact for Earth Day: https://about.fb.com/news/2022/04/make-an-impact-for-earth-day/ Green AI SchrepTech: https://ai.facebook.com/blog/how-ai-is-helping-address-the-climate-crisis/ Timestamps: Intro 0:05 Intro Ramya 2:13 The Cost of AI 3:05 Measuring AI's Carbon Footprint 11:00 Trade Offs 13:28 Calculating the Carbon Intensity 16:01 Mitigation Options 18:36 Cultural Changes 25:35 Societal Value 26:13 Running AI on Edge Devices 29:02 What's Next? 32:33 Outro 34:55

Amy, an experienced iOS developer at Facebook, shares her journey of joining the company. She discusses developing a separate work chat app for Workplace, challenges of inheriting code from Messenger, and white labeling the app. Other topics include origins and growth, open sourcing plans for Lexical, and challenges with data model.