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Cursor at Grab: Adoption and impact

Adoption overview The illustration below encapsulates how Cursor is scaled across Grab, achieving rapid and widespread adoption that accelerated software development and empowered non-technical teams to build solutions.…

Engineering VP Josh Clemm on how we use knowledge graphs, MCP, and DSPy in Dash

Engineering VP Josh Clemm deep-dives into how we think about knowledge graphs, indexes, MCP, and prompt optimization using tools like DSPy.

Terminally online Mistral Vibe.

Terminally online Mistral Vibe.

Heaps do lie: debugging a memory leak in vLLM.

How Etsy Uses LLMs to Improve Search Relevance

Ever searched for something specific, only to be met with results that are close, but not quite ? On Etsy’s Search Relevance team, that frustration is exactly what we are tackling. Our goal is simple yet ambitious: to he…

Information-Driven Design of Imaging Systems

An encoder (optical system) maps objects to noiseless images, which noise corrupts into measurements. Our information estimator uses only these noisy measurements and a noise model to quantify how well measurements disti…

Lyft’s Feature Store: Architecture, Optimization, and Evolution

Written by Rohan Varshney , with support from Devon Mittow Janice Lee . This article expands upon a presentation from the Feature Store Summit 2025, which can be viewed in full here . There is also another video availabl…

Lyft’s Feature Store: Architecture, Optimization, and Evolution

Written by Rohan Varshney , with support from Devon Mittow Janice Lee . This article expands upon a presentation from the Feature Store Summit 2025, which can be viewed in full here . There is also another video availabl…

Introducing Mistral OCR 3

From Python3.8 to Python3.10: Our Journey Through a Memory Leak

Image generated with ChatGPT (OpenAI), 2025. Intro When working with Python, memory management often feels like a solved problem. The garbage collector quietly does its job, and unlike C or C++, we rarely think about mal…

From Python3.8 to Python3.10: Our Journey Through a Memory Leak

Image generated with ChatGPT (OpenAI), 2025. Intro When working with Python, memory management often feels like a solved problem. The garbage collector quietly does its job, and unlike C or C++, we rarely think about mal…

Introducing: Devstral 2 and Mistral Vibe CLI.

Introducing Mistral 3

Streamlining Security Investigations with Agents

Slack’s Security Engineering team is responsible for protecting Slack’s core infrastructure and services. Our security event ingestion pipeline handles billions of events per day from a diverse array of data sources. Rev…

Reducing experiment duration with predicted control variates

I n 2021, we published a blog post titled “ Increasing experimentation accuracy and speed by using control variates ,” describing how we reduce the variance of metrics using CUPED in our experimentation platform. This is…

Mistral AI - KI für Deutschland | Mistral AI

Android VPAT journey

Background A Voluntary Product Accessibility Template (VPAT) is a document that outlines how well a product aligns with accessibility (a11y) standards. Its primary purpose is to inform customers about a product s a11y fe…

LyftLearn Evolution: Rethinking ML Platform Architecture

Written by Yaroslav Yatsiuk At Lyft, machine learning (ML) is the engine behind our most critical business functions — from dispatch and pricing optimization to fraud detection and support automation. Our ML infrastructu…

LyftLearn Evolution: Rethinking ML Platform Architecture

Written by Yaroslav Yatsiuk At Lyft, machine learning (ML) is the engine behind our most critical business functions — from dispatch and pricing optimization to fraud detection and support automation. Our ML infrastructu…

Building The Intent Engine: How Instacart is Revamping Query Understanding with LLMs

Authors: Yuanzheng Zhu, Guanghua Shu, Raochuan Fan, Vinesh Gudla, Tejaswi Tenneti Introduction When people search for items on Instacart, they don’t always type perfectly worded phrases. They might write “bread no gluten…

Building The Intent Engine: How Instacart is Revamping Query Understanding with LLMs

Authors: Yuanzheng Zhu, Guanghua Shu, Raochuan Fan, Vinesh Gudla, Tejaswi Tenneti Introduction When people search for items on Instacart, they don’t always type perfectly worded phrases. They might write “bread no gluten…

RL without TD learning

In this post, I’ll introduce a reinforcement learning (RL) algorithm based on an “alternative” paradigm: divide and conquer . Unlike traditional methods, this algorithm is not based on temporal difference (TD) learning (…

Improving performance by prefetching product pages from Etsy Search

Rarely are there opportunities for big, bold, game-changing improvements in web performance. The Speculation Rules API (SRA) is a recent browser development that offers just such an opportunity. This post details a joint…

Understanding Etsy’s Vast Inventory with LLMs

For more than 20 years, Etsy has been the destination for human creativity online. Our marketplace is home to more than 100 million special items made, handpicked and designed by more than 5 million sellers. These items…

Unlocking Faster Insights with Experimenter-Defined Segmentations

Imagine you have a fabulous idea to drive more sales on Etsy by giving out free ice cream with every purchase. How would you know if it will actually work? One way to test this out is to run an experiment ! An experiment…

S3 server access logs at scale

Introduction Yelp heavily relies on Amazon S3 (Simple Storage Service) to store a wide variety of data, from images, logs, database backups, and more. Since data is stored on the cloud, we need to carefully manage how th…

Building Etsy Buyer Profiles with LLMs

Every day, shoppers from Etsy's community of nearly 90M buyers visit our marketplace to search for unique, handmade, and vintage items. But with over 100 million listings, how do we help each buyer find exactly what they…

What exactly does word2vec learn?

What exactly does word2vec learn, and how? Answering this question amounts to understanding representation learning in a minimal yet interesting language modeling task. Despite the fact that word2vec is a well-known prec…

Context engineering case studies: Etsy-specific question answering

This post investigates the benefits and limitations of prompt engineering in two instances of AI-assisted onboarding relying on large language model (LLM) technology. Of particular interest is how truthful (and therefore…

CRLite: Fast, private, and comprehensive certificate revocation checking in Firefox

Firefox is now the first and the only browser to deploy fast and comprehensive certificate revocation checking that does not reveal your browsing activity to anyone (not even to Mozilla). Tens of millions of TLS server c…

Exploring CHAOS: Building a Backend for Server-Driven UI

A little while ago, we published a blog post on CHAOS: Yelp’s Unified Framework for Server-Driven UI. We strongly recommend reading that post first to gain a solid understanding of SDUI and the goals of CHAOS. This post…

Whole-Body Conditioned Egocentric Video Prediction

.modal { display: none; position: fixed; z-index: 9999; padding-top: 50px; left: 0; top: 0; width: 100%; height: 100%; overflow: auto; background-color: rgba(0,0,0,0.9); } .modal-content { margin: auto; display: block; m…

Revenue Automation Series: Testing an Integration with Third-Party System

Background As described in the second blog post of Revenue Automation series, Revenue Data Pipeline processes a large amount of data via complex logic transformations to recognize revenue. Thus, developing a robust produ…

PayPal Releases Agentic Toolkit to Accelerate Commerce

The following is a repost from the PayPal Developer Blog . Building on the release of PayPal’s MCP servers , PayPal is excited to introduce the PayPal Agentic Toolkit *. This toolkit empowers developers to seamlessly int…

Defending against Prompt Injection with Structured Queries (StruQ) and Preference Optimization (SecAlign)

Recent advances in Large Language Models (LLMs) enable exciting LLM-integrated applications. However, as LLMs have improved, so have the attacks against them. Prompt injection attack is listed as the #1 threat by OWASP t…

Repurposing Protein Folding Models for Generation with Latent Diffusion

PLAID is a multimodal generative model that simultaneously generates protein 1D sequence and 3D structure, by learning the latent space of protein folding models. The awarding of the 2024 Nobel Prize to AlphaFold2 marks…

PayPal Begins Rollout of MCP Servers to Accelerate Agentic Commerce

The following is a repost from the PayPal Developer Blog by Prakhar Mehrotra, SVP of Artificial Intelligence, PayPal At PayPal, we strive to make it easier for developers to access our services. Today, we are taking the…

Behind the Scenes - A Glimpse into Tax Calculations

In the past, sellers were responsible for managing and fulfilling their own tax obligations. However, more and more jurisdictions are now requiring marketplaces such as Etsy to collect the tax from buyers and remit the t…

Scaling Up Reinforcement Learning for Traffic Smoothing: A 100-AV Highway Deployment

Training Diffusion Models with Reinforcement Learning We deployed 100 reinforcement learning (RL)-controlled cars into rush-hour highway traffic to smooth congestion and reduce fuel consumption for everyone. Our goal is…

Improving Firefox Stability in the Enterprise by Reducing DLL Injection

Beginning in version 138, Firefox will offer an alternative to DLL injection for Data Loss Prevention (DLP) deployments in enterprise environments. DLL Injection DLL injection into Firefox is a topic we’ve covered on the…

Estimating Incremental Lift in Customer Value (Delta CV) using Synthetic Control

How we measure the impact of user actions and product adoptions at PayPal In today’s competitive digital landscape, understanding user interactions with your products is essential for driving revenue and building lasting…

Launching Interop 2025

Interop 2025 continues the mission to make the web more consistent across browsers, building on 2024’s 95% interoperability score. This year, 19 focus areas target key developer needs and long-standing issues, including…

Adopting Jetpack Compose for Etsy’s Android App

One of our Guiding Principles at Etsy is that we “commit to our craft.” This means that we have a culture of learning, in which we’re constantly looking for opportunities to improve and learn, adopt industry best practic…

Introducing Uniffi for React Native: Rust-Powered Turbo Modules

Mozilla and Filament have introduced Uniffi for React Native, a tool that allows developers to leverage the safety and performance benefits of Rust in cross-platform React Native apps. The post Introducing Uniffi for Rea…

Llamafile v0.8.14: a new UI, performance gains, and more

Discover the latest release of Llamafile 0.8.14, an open-source AI tool by Mozilla Builders. With a new command-line chat interface, enhanced performance, and support for powerful models, Llamafile makes it easy to run l…

0Din: A GenAI Bug Bounty Program – Securing Tomorrow’s AI Together

As AI continues to evolve, so do the threats against it. As these GenAI systems become more sophisticated and widely adopted, ensuring their security and ethical use becomes paramount. 0Din is a groundbreaking GenAI bug…

Announcing Official Puppeteer Support for Firefox

We’re pleased to announce that, as of version 23, the Puppeteer browser automation library now has first-class support for Firefox. This means that it’s now easy to write automation and perform end-to-end testing using P…

Machine Learning in Content Moderation at Etsy

At Etsy, we’re focused on elevating the best of our marketplace to help creative entrepreneurs grow their businesses. We continue to invest in making Etsy a safe and trusted place to shop, so sellers’ extraordinary items…

Snapshots for IPC Fuzzing

Process separation remains one of the most important parts of the Firefox security model and securing our IPC (Inter-Process Communication) interfaces is crucial to keep privileges in the different processes separated. W…