Breakpoint

LinkedIn engineering blog

Announcing Our LinkedIn-Cornell 2026 Grant Recipients
LinkedIn announces the 2026 recipients of its Cornell Bowers research grants, supporting projects in AI agents, LLMs, text diffusion, database efficiency, privacy, safety, and recommendation systems. The post also summarizes the partnership’s five-year research impact.
Building LinkedIn Premium All‑in‑One: Unified AI‑Powered Workf...
LinkedIn engineers describe the architecture behind Premium All-in-One, including LLM-based target-audience inference, activity signals with time decay, embedding and index-based prospect retrieval, and targeted post scoring. The post also covers privacy guardrails, experimentation, staged rollouts, and lessons from unifying systems across multiple product lines.
High-Signal AI Code Review That Adapts to Your Codebase at Scale
LinkedIn describes how it built a customized multi-agent AI code review system that scales across thousands of repositories while producing high-signal, actionable feedback. The post explains the orchestration, deduplication, customization framework, and evaluation methods behind the system, including its acceptance rates, infrastructure, and plans to extend review beyond comments and into production incident learning.
Quality Assurance Agent: Reimagining Software Quality with AI-Driven Autonomous Testing
This post describes LinkedIn’s Quality Assurance Agent, an autonomous testing system that uses generative AI and vision-language models to navigate mobile and web applications like a human tester. It explains the hybrid architecture, guardrail evaluators, and golden dataset evaluation framework that enable reliable bug detection, self-healing test execution, and broader participation in quality assurance across teams.
Accelerating Go-To-Market Velocity with the Product Configuration Center
This post describes LinkedIn’s Product Configuration Center (PCC), a centralized platform designed to replace fragmented, manual configuration workflows across monetization domains. It explains how PCC uses structured change requests, Temporal-based orchestration, SAGA patterns, and deterministic identifiers to reduce launch cycles, eliminate drift-related incidents, and create a safer foundation for AI-assisted configuration changes.
Semantic Search for AI Agents at Scale: Retrieval and Ranking for LinkedIn’s Hiring Assistant
This post explains how LinkedIn built semantic search for its Hiring Assistant to match recruiter queries against more than a billion member profiles using AI agents and embedding-based retrieval. It details the MUSE system’s teacher-student supervision approach, Matryoshka embeddings, billion-scale production architecture, and evaluation framework, showing how the team improved candidate relevance, liquidity, and recruiter engagement at scale.
Faster than Light: Optimizing Generative Recommender Training Efficiency at LinkedIn
LinkedIn describes how it improved training efficiency for its Generative Recommender systems by addressing data pipeline, attention kernel, embedding, evaluation, and distributed training bottlenecks. The post details a series of system-level optimizations, including fused dataloading, FlashAttention-3, FlexAttention, packed sequences, HSDP, and incremental training, that collectively reduced GPU hours by up to 65% without hurting model quality.
Crosscheck: Benchmarking AI models in the real world
LinkedIn introduces Crosscheck, a benchmarking platform that compares AI models in real-world professional contexts rather than relying on generic leaderboards. The post explains the statistical and product design choices behind Crosscheck, including Bradley-Terry ranking, time-decay weighting, regularization, confidence-aware tiering, and active sampling to produce more reliable, segment-specific model evaluations.
The 58-Million-Key Freeze: What a HashMap Resize Taught Us About Memory Allocation at Scale
This post investigates intermittent 15-second freezes in LinkedIn’s FishDB feed retrieval service and traces them to a cascade of kernel-level lock contention. Through automated off-CPU profiling with eBPF, the team discovers that a HashMap resize at around 58.7 million keys triggered a large mmap allocation, blocking page faults and memory purging across Tokio worker threads. The fix was to pre-allocate the HashMap capacity at startup, eliminating the resize and the resulting availability drops.
AI helping build better AI: How agents accelerate Liger Kernel engineering
This post explains how LinkedIn uses agentic workflows to accelerate Liger Kernel engineering across kernel creation, model integration, and performance optimization. It highlights a structured three-stage process—understand, act, and verify—that helps agents generate shippable Triton kernels, automate HuggingFace model support, and improve GPU performance with measurable speedups and memory reductions.
Managing software license lifecycles: the SLLM journey
This post explains how LinkedIn built SLLM, a centralized software license lifecycle management platform to automate provisioning and reclamation across hundreds of third-party applications. It details the system’s phased rollout, including intelligent reclamation, request-based and zero-touch provisioning, batch processing, configuration-driven design, and the safeguards that helped improve efficiency, visibility, compliance, and employee experience.
Building LinkedIn’s CTV Ads: Scaling professional reach to the big screen
This post explains how LinkedIn built and scaled its Connected TV (CTV) ads offering to deliver professional audiences on premium streaming devices. It details the engineering behind supply management, brand safety, identity matching, creative validation, measurement, and VAST tag support, showing how LinkedIn balanced advertiser performance with publisher quality requirements.