diff --git a/README.md b/README.md
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+++ b/README.md
@@ -676,6 +676,7 @@ An updated and organized reading list for illustrating the patterns of scalable,
 	* [Building a scalable data management system for computer vision tasks at Pinterest](https://medium.com/@Pinterest_Engineering/building-a-scalable-data-management-system-for-computer-vision-tasks-a6dee8f1c580)
 	* [Structured Data at Etsy](https://codeascraft.com/2019/07/31/an-introduction-to-structured-data-at-etsy/)
 	* [Scaling a Mature Data Pipeline - Managing Overhead at Airbnb](https://medium.com/airbnb-engineering/scaling-a-mature-data-pipeline-managing-overhead-f34835cbc866)
+	* [Spark Partitioning Strategies at Airbnb](https://medium.com/airbnb-engineering/on-spark-hive-and-small-files-an-in-depth-look-at-spark-partitioning-strategies-a9a364f908)
 * [Distributed Machine Learning](https://www.csie.ntu.edu.tw/~cjlin/talks/bigdata-bilbao.pdf)
 	* [Aroma: Using ML for Code Recommendation at Facebook](https://code.fb.com/developer-tools/aroma/)
 	* [Flyte: Cloud Native Machine Learning and Data Processing Platform at Lyft](https://eng.lyft.com/introducing-flyte-cloud-native-machine-learning-and-data-processing-platform-fb2bb3046a59)
@@ -741,7 +742,6 @@ An updated and organized reading list for illustrating the patterns of scalable,
 	* [Architecting Restaurant Wait Time Predictions at Yelp](https://engineeringblog.yelp.com/2019/12/architecting-wait-time-estimations.html)
 	* [Music Personalization at Spotify](https://labs.spotify.com/2016/08/07/commodity-music-ml-services/)
 	* [Deep Learning for Domain Name Valuation at GoDaddy](https://sg.godaddy.com/engineering/2019/07/26/domain-name-valuation/)
-	* [Spark Partitioning Strategies at Airbnb](https://medium.com/airbnb-engineering/on-spark-hive-and-small-files-an-in-depth-look-at-spark-partitioning-strategies-a9a364f908)
 
 ## Architecture
 * [Systems We Make](https://systemswemake.com/)
@@ -752,6 +752,7 @@ An updated and organized reading list for illustrating the patterns of scalable,
 * [Architecture of Evernote](https://evernote.com/blog/a-digest-of-evernotes-architecture/)
 * [Architecture of Chat Service (3 parts) at Riot Games](https://engineering.riotgames.com/news/chat-service-architecture-persistence)
 * [Architecture of League of Legends Client Update](https://technology.riotgames.com/news/architecture-league-client-update)
+* [Architecture of Ad Platform at Twitter](https://blog.twitter.com/engineering/en_us/topics/infrastructure/2020/building-twitters-ad-platform-architecture-for-the-future.html)
 * [Basic Architecture of Slack](https://slack.engineering/how-slack-built-shared-channels-8d42c895b19f)
 * [Back-end at LinkedIn](https://engineering.linkedin.com/architecture/brief-history-scaling-linkedin)
 * [Back-end at Flickr](https://yahooeng.tumblr.com/post/157200523046/introducing-tripod-flickrs-backend-refactored)