Online & Adaptive Recommender System (OARS)
@ ACM RecSys 2026
Real-time personalization · Agentic AI · LLM-powered recommendation
Join leading researchers and practitioners shaping the future of personalization
September 28, 2026
Register

Overview

Recommender systems (RecSys) play a central role in helping users navigate and discover content in large, constantly evolving information spaces. However, many deployed systems still rely on static user profiles and precomputed recommendations, limiting their ability to adapt within and across sessions. As personalization demands intensify, privacy regulations tighten, and user intent grows more dynamic, the need for online and adaptive recommender systems has never been greater.

The Online and Adaptive Recommender Systems (OARS) workshop brings together researchers and practitioners from academia and industry to share advances in real-time and adaptive recommender systems. We invite submission of papers and posters, representing new researches, positions, and proposals for new tools, datasets, and resources. All submitted papers will be peer reviewed by an international program committee of researchers of high repute. Accepted submissions will be presented at the workshop.

Topics

🤖 Agentic RecSys

  • Agentic recommender systems, assistant-style interfaces, memory and tool-use (2026 special theme)
  • LLMs and foundation models in RecSys: semantic IDs, tokenization, multi-modality, in-context learning

⚡ Online, Adaptive & Interactive Learning

  • Online and continual learning, reinforcement learning, bandits, and counterfactual evaluation
  • Real-time user intent modeling, session-aware and conversational recommendation

🏗️ Recommender Architectures & Infrastructure

  • RAG-based, streaming, and event-driven architectures for scalable learning
  • Industry deployments, infrastructure, and real-world case studies

🧩 Data Quality, Robustness & Distribution Shift

  • Cold-start, distribution shift, and robustness under data sparsity

📊 Evaluation, Causality & Explainability

  • Evaluation, explanation, off-policy, and continuous learning methods for OARS
  • Predictive analytics and causal inference for recommendation

🔒 Privacy, Fairness, Ethics & User Welfare

  • Privacy, ethics, fairness, and user welfare in OARS

Call for Papers

Download CFP

All papers will be peer reviewed (double-blind) by the program committee and judged by their relevance to the workshop, especially to the main themes identified above, and their potential to generate discussion.

All submissions must be formatted according to the latest ACM SIG proceedings template (two column format). One recommended setting for Latex file of manuscript is: \documentclass[sigconf, anonymous, review]{acmart}. Submissions must describe work that is not previously published, not accepted for publication elsewhere, and not currently under review elsewhere. All submissions must be in English.

Please note that at least one of the authors of each accepted paper must register for the workshop and attend in person to present the paper during the workshop.

Submissions to the OARS workshop should be made to the track of Online and Adaptive Recommender System at this Easychair page.

📅 Important Dates

Submissions Due July 20, 2026
Notification August 10, 2026
Camera Ready Version Due August 28, 2026
Workshop Day September 28, 2026


Feedback and stay updated to the workshop

Schedule

Details Will Come Soon...

Time Talk
1:00-1:05 ET Opening
1:05-1:50 ET Invited Talk 1
TBD
TBD
TBD
1:50-2:05 ET Spotlight 1
Rethinking ANN-based Retrieval: Multifaceted Learnable Index for Large-scale Recommendation System [paper]
Jiang Zhang, Yubo Wang, Wei Chang, Lu Han, Xingying Cheng, Feng Zhang, Min Li, Songhao Jiang, Wei Zheng, Harry Tran, Zhen Wang, Lei Chen, Yueming Wang, Benyu Zhang, Xiangjun Fan, Bi Xue and Qifan Wang.
2:05-2:20 ET Spotlight 2
Real-Time Hard Negative Sampling via LLM-based Clustering for Large-Scale Two-Tower Retrieval [paper]
Zihao Zhao, Ivan Ji, Liuyi Hu, Lei Huang, Qunshu Zhang, Xiangjun Fan and Aameek Singh
2:20-2:35 ET Spotlight 3
Lightweight Ranking Heads: Accelerating Multi-Task Experimentation in Production Recommender Systems [paper]
Sanjay Surendranath Girija, Aniruddh Nath, Li Wei, Yanhao Jiang, Shawn Andrews, Lukasz Heldt, Yi Wu, Aditya Mahajan and Mohit Sharma
2:35-2:50 ET Spotlight 4
Beyond Co-purchase Relation: Evolution of Complementary Recommendations at Allegro [paper]
Aleksandra Osowska-Kurczab, Klaudia Nazarko, Eliška Kosturová, Lidia Wojciechowska and Michał Bień
2:50-3:35 ET Invited Talk 2
TBD
TBD
TBD
3:35-3:50 ET Spotlight 5
Addressing Intent-Impression Misalignment in Multi-Vertical Marketplaces via Query-Level Multinomial Blending [paper]
Beatrice Musizza and Thorsten Krause
3:50-4:05 ET Spotlight 6
A Benchmark Suite for Online Learning of Non-Stationary User Preferences in Recommender Systems [paper]
Tonmoy Hasan, Wenyu Gao and Razvan Bunescu
4:05-4:20 ET Spotlight 7
Quantifying the Cost of DPP Diversity in Shopify's Mobile Commerce Feed [paper]
Jeff Kahn and Chen Karako
4:05-4:20 ET Spotlight 8
Next Best Action Causal Constrained Offline RL for Business Action Targeting [paper]
Surya Ramachandiran, Yiming Li, Juan Mancilla-Caceres, Tao Ye and Jun Liu
4:05-4:20 ET Spotlight 9
BAFF: Bid-Aware Filter Family for Mitigating Training Data Interference in RTB A/B Tests [paper]
Jeonglyul Oh, Ikkyu Choi, Inseop Youn and Youngjae Kim
4:05-4:20 ET Spotlight 10
Billion-Scale Thumbnail Optimization for Uncurated Short-Form Videos via Multi-Armed Bandits [paper]
Ling Liu, Ying Han, Fabio Soldo, Vu Nguyen, Danio Wang, Liz Kidd, Yongle Cao, Theodore Rose, Su-Lin Wu and Romer Rosales
4:20-5:05 ET Invited Talk 3
TBD
TBD
TBD
5:05-5:10 ET Closing
12:00-1:30 ET Poster Session
Poster 1
CORAL: An LLM-Native Harness for Production Recommender Systems [paper]
Muhammad Rafay Azhar, Yuhang Zhou, Gilbert Jiang, Yuchen Wang, Rahul Sharma, Matthew DeSousa, Jiayi Liu, Xin Guo, Lizhu Zhang and Xiangjun Fan
Poster 2
MoFA: LLM-Driven Reasoning for Constraint-Aware Feature Selection in Industrial ML Systems [paper]
Yuhang Zhou, Zhuokai Zhao, Ke Li, Spilios Evmorfos, Gökalp Demirci, Mingyi Wang, Qiao Liu, Qifei Wang, Serena Li, Weiwei Li, Tingting Wang, Mingze Gao, Gedi Zhou, Abhishek Kumar, Xiangjun Fan, Lizhu Zhang and Jiayi Liu
Poster 3
Billion-Scale Thumbnail Optimization for Uncurated Short-Form Videos via Multi-Armed Bandits [paper]
Ling Liu, Ying Han, Fabio Soldo, Vu Nguyen, Danio Wang, Liz Kidd, Yongle Cao, Theodore Rose, Su-Lin Wu and Romer Rosales
Poster 4
Billion-Scale Thumbnail Optimization for Uncurated Short-Form Videos via Multi-Armed Bandits [paper]
Ling Liu, Ying Han, Fabio Soldo, Vu Nguyen, Danio Wang, Liz Kidd, Yongle Cao, Theodore Rose, Su-Lin Wu and Romer Rosales
Poster 5
Billion-Scale Thumbnail Optimization for Uncurated Short-Form Videos via Multi-Armed Bandits [paper]
Ling Liu, Ying Han, Fabio Soldo, Vu Nguyen, Danio Wang, Liz Kidd, Yongle Cao, Theodore Rose, Su-Lin Wu and Romer Rosales
Poster 6
Billion-Scale Thumbnail Optimization for Uncurated Short-Form Videos via Multi-Armed Bandits [paper]
Ling Liu, Ying Han, Fabio Soldo, Vu Nguyen, Danio Wang, Liz Kidd, Yongle Cao, Theodore Rose, Su-Lin Wu and Romer Rosales
Poster 7
Billion-Scale Thumbnail Optimization for Uncurated Short-Form Videos via Multi-Armed Bandits [paper]
Ling Liu, Ying Han, Fabio Soldo, Vu Nguyen, Danio Wang, Liz Kidd, Yongle Cao, Theodore Rose, Su-Lin Wu and Romer Rosales
Poster 8
Billion-Scale Thumbnail Optimization for Uncurated Short-Form Videos via Multi-Armed Bandits [paper]
Ling Liu, Ying Han, Fabio Soldo, Vu Nguyen, Danio Wang, Liz Kidd, Yongle Cao, Theodore Rose, Su-Lin Wu and Romer Rosales
Poster 9
Billion-Scale Thumbnail Optimization for Uncurated Short-Form Videos via Multi-Armed Bandits [paper]
Ling Liu, Ying Han, Fabio Soldo, Vu Nguyen, Danio Wang, Liz Kidd, Yongle Cao, Theodore Rose, Su-Lin Wu and Romer Rosales

Registration

Register at RecSys 2026

Invited Speakers

James Caverlee

Texas A&M University
College Station, TX
 

Colin McFarland

Microsoft
Mountain View, CA
 

Sudeep Das

DoorDash
San Francisco, CA
 

Workshop Organizers

 
 

Xiquan Cui

Workday
Senior Manager, ML

Derek Cheng

Google DeepMind
Mountain View, CA
 

Fei Liu

Emory
Atlanta, GA
 

Tao Ye

Lyft
San Francisco, CA
 

 
 
 

Julian McAuley

University of California San Diego
San Diego, CA

Vachik Dave

Walmart Global Tech
Sunnyvale, CA
 

Stephen Guo

Indeed
San Francisco, CA
 

Program Committee

Kai Zhao, Workday

Preetham Kaukuntla, Indeed

Rajat Shah, Netflix

Abhishek Maligehalli Shivalingaiah, AWS

Rahul Mayuranath, OpenAI

Sanjeev Suresh, Uber

Srijith Ravikumar, Amazon

Meghana Nagendra Babu, Apple

Sachin Bhandarkar, GEICO

Deepesh Hada, Microsoft

Vinay Shetty, Roku

Zhankui He, Google

Rahul Sharnagat, Walmart

Prateek Sharma, Meta

Raja Sekhar Rao Dheekonda, Dreadnode

Contact us

Please send questions and enquiries to xiquan.cui@workday.com.