google

Generating synthetic data with differentially private LLM inference (opens in new tab)

Researchers at Google have developed an inference-only method for generating differentially private (DP) synthetic data that avoids the high costs and data requirements associated with private fine-tuning. By prompting off-the-shelf large language models (LLMs) with sensitive examples in parallel and aggregating their outputs, the approach can generate thousands of high-quality synthetic data points while maintaining rigorous privacy guarantees. This method allows synthetic data to serve as a secure interface for model development, enabling teams to collaborate without requiring specialized knowledge of differential privacy. ## Differentially Private Prediction and Aggregation The core of this method relies on "private prediction," where privacy is applied to the model's output rather than the model itself. * Sensitive data points are distributed across multiple independent prompts, ensuring that no single individual's record can significantly influence the final output. * The LLM generates next-token predictions for each prompt in parallel, which are then aggregated to mask individual contributions. * The researchers designed a DP token sampling algorithm that treats the standard LLM "softmax" sampling process as a version of the exponential mechanism, a mathematical framework used to select the best option from a set while maintaining privacy. ## Enhancing Efficiency via KV Caching Previous attempts at private prediction were computationally expensive because they required a fresh batch of sensitive examples for every single token generated. * A new privacy analysis allows the system to reuse a fixed batch of sensitive examples across an entire generation sequence. * By maintaining the same context for each generation step, the system becomes compatible with standard inference optimization techniques like KV (Key-Value) caching. * This improvement enables the generation of synthetic data at a scale two to three orders of magnitude larger than prior methods. ## Optimizing Privacy Spend with Public Drafters To preserve the "privacy budget"—the limited amount of information that can be released before privacy is compromised—the method introduces a public drafter model. * The drafter model predicts the next token based solely on previously generated synthetic text, without ever seeing the sensitive data. * Using the sparse vector technique, the system only consumes the privacy budget when the public drafter’s suggestion disagrees with the private aggregate of the sensitive data. * This is particularly useful for structured data, where the drafter can handle formatting and syntax tokens, saving the privacy budget for the actual content. By leveraging off-the-shelf models like Gemma, this approach provides a scalable way to transform sensitive datasets into useful synthetic versions. These synthetic datasets are high-quality enough to replace real data in downstream machine learning tasks, such as in-context learning or fine-tuning models like BERT, without the risk of leaking individual user information.

discord

Modern Image Formats at Discord: Supporting WebP and AVIF (opens in new tab)

Discord’s Media Infrastructure team has modernized its image pipeline by integrating support for animated WebP and AVIF formats across its entire platform. This update ensures that attachments, embeds, and animated emojis are delivered using high-efficiency codecs that maintain visual fidelity while minimizing resource consumption. By adopting these modern standards, Discord has optimized the balance between high-quality animation and fast, cross-platform playback performance. **Expansion of Format Support** * Native support for animated WebP and AVIF has been added for all user-generated attachments and embedded media. * The platform has transitioned all animated emojis to serve as animated WebP, ensuring a consistent viewing experience across desktop, web, and mobile clients. * The pipeline update allows for a unified delivery system that handles modern media containers seamlessly across different device architectures. **Performance and Infrastructure Benefits** * The shift to modern codecs has resulted in a drastic decrease in file sizes, which directly translates to faster loading times for users on limited bandwidth. * Enhanced playback performance reduces the computational overhead required to render complex animations. * Higher visual quality is maintained even at lower bitrates, allowing for richer media experiences without increasing data costs. For developers and platforms managing high-volume media assets, transitioning to animated WebP and AVIF represents a necessary evolution to meet modern performance expectations. Implementing these formats provides a scalable way to deliver high-fidelity content while significantly reducing storage and bandwidth requirements.

discord

Announcing Discord’s Social SDK, Helping Power Your Game’s Social Experiences (opens in new tab)

Discord has launched the Discord Social SDK, a free toolkit that allows game developers to integrate Discord's social infrastructure directly into their titles to drive player engagement and discovery. The SDK enables features like friends lists and messaging for all players, regardless of whether they have a Discord account, while offering deeper integration for those who choose to link their profiles. By tapping into Discord’s ecosystem of over 200 million monthly active users, the tool aims to help developers overcome discovery challenges in a market where a small number of franchises dominate total playtime. **Solving Discovery Through Social Connectivity** * With 20,000 games launching annually, Discord aims to leverage the fact that 50% of its users discover a new game on the platform every month. * Internal data suggests that playing with at least one friend increases gameplay session lengths sevenfold. * The SDK facilitates "friend-to-friend influence," where 28% of users launch a game within an hour of watching a friend stream it on the platform. **Core SDK Integration Features** * **Unified Friends List:** Synchronizes in-game and Discord friends lists, allowing players to maintain connections both inside and outside the game environment. * **Deep-linked Game Invites:** Enables players to send invites from their in-game list that allow Discord friends to join a specific party, lobby, or session with a single click. * **Rich Presence:** Displays real-time gaming activity on Discord profiles across PC, console, and mobile, serving as a passive discovery tool for a player's social circle. * **Flexible Account Requirements:** Developers can provide a unified social experience to all players without requiring a Discord login, though account linking unlocks more persistent social features. **Advanced Communication Tools in Beta** * **Cross-Platform Messaging:** A closed beta feature that allows players to continue game-related conversations across desktop, console, and mobile devices. * **Linked Channels:** Enables developers to sync in-game chat with specific Discord server channels, providing persistent messaging for guilds and squads. * **Integrated Voice Chat:** Grants developers access to Discord’s proprietary high-quality audio technology to power in-game voice communications. **Technical Specifications and Partnerships** * The SDK is currently available for C++, Unreal Engine, and Unity developers. * Initial support covers Windows 11+ and macOS, with console and mobile support listed as coming soon. * Early adoption partners include major studios such as Theorycraft Games, Facepunch Studios, 1047 Games, and Scopely. By providing these social tools for free, Discord is positioning itself as the foundational social layer for the gaming industry. Developers looking to capitalize on existing social graphs and improve player retention should consider integrating the SDK to bridge the gap between their game and the "digital living rooms" where players already spend their time.

discord

The Game Developer Playbook: Three Incredible Game-Focused Communities (opens in new tab)

Discord suggests that there is no universal set of "best practices" for managing a community, as every server has unique requirements that demand creative, tailored solutions. By analyzing high-performing communities through Server Discovery, developers can find inspiration to iterate on their own structures and engagement strategies. This approach emphasizes that true success is measured by active engagement rather than raw member counts. ## Leveraging Server Discovery for Community Inspiration * Server Discovery serves as a primary research tool for developers to observe how successful communities are structured and operated. * Success should be evaluated based on engagement levels rather than the total number of members in a community. * Research should extend beyond featured pages to include servers with similar topics or even non-gaming communities to find adaptable ideas. ## Analyzing Best-in-Class Multiplayer Communities * The guide highlights three specific communities—Fortnite, Rocket League, and Deep Rock Galactic—as models for effective server architecture. * Each of these servers demonstrates how to align technical setups with specific marketing goals and community needs. * The analysis goes beyond basic configurations, exploring advanced implementations of categories, channels, and permission systems to enhance user experience. To build a comprehensive community strategy, developers should review these case studies in conjunction with earlier phases of the GameDev Playbook, specifically focusing on the transitions from private playtest environments to early access and pre-launch configurations.

discord

Discord Patch Notes: March 11, 2025 (opens in new tab)

Discord's "Patch Notes" series provides an overview of technical enhancements aimed at improving the platform's performance, responsiveness, and general stability. By bridging the gap between developers and the community, the initiative encourages active participation in identifying bugs and testing upcoming features. ### Community-Driven Bug Tracking * Users can report technical issues through the Bimonthly Bug Megathread located on the community-managed r/DiscordApp subreddit. * Discord’s engineering team monitors these community reports directly to prioritize fixes and address specific usability grievances. * This collaborative approach allows the team to identify edge cases that might be missed during internal testing. ### iOS Early Access via TestFlight * Discord offers an opt-in TestFlight version for iOS users who want to trial features before their official public release. * Testers can access this build via the dis.gd/testflight link to help identify "pesky bugs" in real-world environments. * This beta testing phase acts as a critical quality assurance layer to ensure stability for the broader user base. ### Update Deployment and Merging * All documented fixes and performance improvements have been officially committed and merged into the platform's codebase. * Although the code is finalized, the actual deployment is incremental, meaning updates may roll out to different platforms at varying times. To contribute to a more stable experience, users should utilize the dedicated subreddit for reporting persistent bugs or enroll in the TestFlight program to provide feedback on pre-release builds.

discord

Supercharging Discord Mobile: Our Journey to a Faster App (opens in new tab)

Discord leverages React and React Native to maintain high development velocity across desktop and mobile platforms while navigating the performance constraints of cross-platform frameworks. After initially avoiding React Native for Android due to hardware limitations, the company transitioned its client in 2022 by utilizing the Hermes JavaScript engine and targeting improved device capabilities. This strategic shift has allowed for significant efficiency gains, including a 50% reduction in median startup times as the team shifts focus toward optimizing experiences for power users. ### Cross-Platform Development and Android Transition * Discord uses React for desktop and React Native for mobile to allow unified feature shipping across platforms. * The company originally delayed adopting React Native on Android to avoid performance degradation on a wide range of hardware. * The formal transition to React Native for Android occurred in 2022, spurred by the introduction of Hermes, a JavaScript engine optimized for React Native. ### Performance Optimization and Efficiency * React Native introduced specific trade-offs, particularly regarding startup times on lower-end Android devices. * Discord’s engineering team successfully halved median startup times throughout 2023 through focused architectural improvements. * Current development efforts are prioritizing performance for "power users" who push the app's limits, ensuring stability and speed for high-intensity use cases. Discord’s journey highlights that while cross-platform frameworks like React Native require rigorous optimization—especially on Android—the trade-off for development speed and feature parity is increasingly viable through modern tools like the Hermes engine.

discord

December Staff Picks: It’s Giving Games (opens in new tab)

This blog post explores the addictive nature of modern gaming hits like *Balatro* and the profound personal impact of receiving the right game as a gift. It highlights how certain titles act as "canon events" in a person’s life, permanently altering their interests and gaming habits. The discussion serves as a platform for various contributors to share their recent gaming experiences and the specific titles that shaped their history with the medium. **The Balatro Craze** * The game is recognized as the "mobile game of the year" following accolades from The Game Awards. * The mechanics involve complex card-based synergies, such as combining a Queen card with the Photograph Joker and the Sock & Buskin Joker to trigger multiple score multipliers. * The author notes the game’s extreme "time-sink" potential, making it a powerful but potentially disruptive gift for friends. **Gifting and Gaming Canon Events** * The post centers on the concept of "canon event" games—titles that are so influential they fundamentally change the player’s perspective on gaming. * Specific mention is made of *Tony Hawk’s Underground 2* as a transformative title for the author. * The piece introduces insights from a panel of contributors, including Emi, Matt, Cody, and a new addition, Scott, who discuss their personal histories with gifted games. If you are looking for a gift that might "alter the brain chemistry" of a friend, consider titles with deep mechanical loops like *Balatro*, but be prepared for them to disappear into the game for a few months.

discord

Discord Patch Notes: February 3, 2025 (opens in new tab)

Discord’s "Patch Notes" series serves as a transparent log of the platform's continuous efforts to enhance performance, reliability, and overall usability. The series highlights finalized engineering commits aimed at resolving bugs and improving system responsiveness across all supported platforms. **System Maintenance and Rollout Strategy** * Engineering efforts focus on core platform metrics, specifically addressing application responsiveness, stability, and general bug fixes. * While all listed updates are committed and merged into the codebase prior to publication, the actual deployment occurs via rolling releases, meaning features may arrive on different platforms at different times. **Collaborative Bug Identification** * Discord leverages the community-managed r/DiscordApp subreddit to facilitate direct communication between the user base and the development team. * A dedicated Bimonthly Bug Megathread serves as the primary intake channel for identifying new issues, which the engineering team then investigates for future patches. Users are encouraged to keep their applications updated to the latest version and utilize the official community threads to report any persistent technical issues.

discord

Measuring Product Impact Without A/B Testing: How Discord Used the Synthetic Control Method for Voice Messages (opens in new tab)

When Discord launched Voice Messages in 2023, the engineering and data teams faced a significant hurdle in measuring the feature's impact through traditional A/B testing. Because the feature is inherently social—requiring both a sender and a receiver—standard user-level randomization would fail to capture the true causal effect due to heavy network interference. The team had to navigate the limitations of their testing infrastructure, ultimately seeking a balance between imperfect user-level tests and geographically biased alternatives. ### The Conflict Between Social Features and SUTVA * Traditional A/B testing relies on the Stable Unit Treatment Value Assumption (SUTVA), which posits that the behavior of one user is independent of the treatment assignment of others. * Voice Messages break this assumption because the feature’s value is realized through interactions; if a sender is in the treatment group but the receiver is in control, the experimental boundaries blur. * Network effects occur when treatment behavior in one group influences the control group, potentially skewing metrics and leading to an inaccurate understanding of the feature's success. ### Infrastructure Constraints and Randomization Strategies * The ideal solution for social platforms is cluster randomization, which assigns entire networks or communities to a single experimental arm to contain interactions. * Discord’s internal testing platform did not support cluster randomization at the time of the Voice Message launch, forcing the team to consider less-than-ideal methodologies. * User-level randomization was deemed "bad" for this specific use case because it could not account for the interconnected nature of Discord’s user base. ### The Trade-offs of Geo-Testing * One proposed alternative was randomizing by country, based on the assumption that most social networks are language or country-specific. * By treating an entire geographic region while keeping another as a control, the team hoped to mitigate cross-group network interference. * However, geo-testing introduces significant bias, as it conflates the treatment effect with existing cultural, economic, and behavioral differences between countries. To accurately measure the impact of features built on social connectivity, organizations must account for network interference that violates standard statistical assumptions. When cluster randomization infrastructure is unavailable, data teams must carefully weigh the bias introduced by geographic testing against the interference inherent in user-level randomization.