SDI References volumes 1 & 2

What changed

Every link is re-checked on a schedule. This is what the checks have found: references that stopped resolving, ones that came back, and documents rewritten where they stand. Right now 31 links are not resolving, out of 462 checked.

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Link changes by month, most recent first.
MonthBrokeRecovered RewrittenAddedShape
August 2026 462
  1. added, unreachable 522 Epoch Chapter 13
  2. added, blocked 429 Payments Integration at Uber: A Case Study – Gergely Orosz Chapter 11
  3. added, blocked 429 YouTube scalability talk by early YouTube employee Chapter 14
  4. added, blocked 429 Differential Synchronization youtube talk Chapter 15
  5. added, blocked 429 Erasure Coding Demystified Chapter 9
  6. added, blocked 429 End-to-end Exactly-once Aggregation Over Ad Streams Chapter 6
  7. added, blocked 429 Geospatial Indexing: The 10 Million QPS Redis Architecture Powering Lyft Chapter 1
  8. added 200 Weibo video processing architecture (in Chinese) Chapter 14
  9. added 200 Apache ZooKeeper Chapter 12
  10. added 200 Unicode frequently asked questions Chapter 13
  11. added, blocked 429 Reliable Processing in a Streaming Payment System Chapter 11
  12. added 200 YogabyteDB Chapter 11
  13. added, blocked 429 Yahoo Company engineering blogs
  14. added, blocked 429 How We've Scaled Dropbox Chapter 15
  15. added 200 Understanding MapReduce in Hadoop Chapter 6
  16. added 200 QQ Email System Optimization (in Chinese) Chapter 8
  17. added 200 SQLite Chapter 12
  18. added 200 Global spam volume Chapter 8
  19. added 200 Messenger and WhatsApp process 60 billion messages a day Chapter 12
  20. added, blocked 403 Thumbtack Company engineering blogs
  21. added, blocked 403 Consistent hashing Chapter 9
  22. added 200 Twilio SMS Chapter 10
  23. added 200 Scaling Memcache at Facebook Chapter 1
  24. added, robots.txt Yelp Chapter 1
  25. added, robots.txt Yelp business endpoints Chapter 1
  26. added, blocked 429 Microsoft Exchange Conference 2014 Search in Exchange Chapter 8
  27. added 200 OTP Chapter 2
  28. added 200 From nothing: the evolution of WeChat background system (Article in Chinese) Chapter 12
  29. added, unreachable 402 Order book Chapter 13
  30. added 200 Geohash Chapter 1
  31. added, blocked 403 Nexmo SMS Chapter 10
  32. added 200 YouTube by the numbers Chapter 14
  33. added 200 OpenStreetMap Chapter 1
  34. added 200 PagerDuty Chapter 5
  35. added, blocked 403 PayPal Company engineering blogs
  36. added 200 Queue Length Limit Chapter 4
  37. added 200 A RESTful Tutorial Chapter 8
  38. added 200 Splunk Chapter 5
  39. added 200 A brief introduction to BEAM Chapter 2
  40. added 200 Donald J. Patterson, Web Crawling Chapter 9
  41. added 200 Why We’re Building Flux, a New Data Scripting and Query Language Chapter 5
  42. added 200 Message threading Chapter 8
  43. added 200 LMAX exchange was famous for its open-source Disruptor Chapter 13
  44. added, blocked 403 US Library of Congress Chapter 9
  45. added 200 MySQL Chapter 5
  46. added 200 NYSE matched volume Chapter 13
  47. added 200 Erlang Chapter 2
  48. added 200 What is avro Chapter 6
  49. added 200 SSTable Chapter 9
  50. added 200 InfluxDB Chapter 5
  51. added 200 Scale at Facebook Real-world systems
  52. added, unreachable 402 Dark pool Chapter 13
  53. added 200 Webhooks Chapter 11
  54. added 200 Kafka Connect Deep Dive – Error Handling and Dead Letter Queues Chapter 11
  55. added 202 Fix trading Chapter 13
  56. added 200 Google Drive Chapter 15
  57. added, gone 404 HKEX daily trading volume Chapter 13
  58. added 200 IBM microservices Chapter 4
  59. added, unreachable Prefix Hash Tree An Indexing Data Structure over Distributed Hash Tables Chapter 13
  60. added 200 Hands-free Kafka Replication Chapter 4
  61. added 200 Digimarc Chapter 9
  62. added, robots.txt Dropbox security white paper Chapter 15
  63. added 200 Leaderboard & Write Sharding Chapter 10
  64. added 200 Elastic stack Chapter 5
  65. added, robots.txt Geo Shape Type Chapter 1
  66. added 200 Erlang at Facebook Chapter 12
  67. added, robots.txt How News Feed Works Chapter 11
  68. added, robots.txt The Life of a Typeahead Query Chapter 13
  69. added, robots.txt The Underlying Technology of Messages Chapter 12
  70. added 200 Ad traffic quality Chapter 6
  71. added 200 gRPC Chapter 7
  72. added 200 Customize your success page Chapter 11
  73. added, blocked 403 What is edge computing Chapter 4
  74. added, gone 404 ISR in Apache Kafka Chapter 4
  75. added 200 SAGAS, HectorGarcia-Molina Chapter 12
  76. added 200 SVE: Distributed Video Processing at Facebook Scale Chapter 14
  77. added 200 Here's What You Need to Know About Streaming Protocols Chapter 14
  78. added 200 Datadog Chapter 5
  79. added 200 Big Data Chapter 6
  80. added 200 Stripe idempotent requests Chapter 11
  81. added 200 The rsync algorithm Chapter 15
  82. added 200 What Are The Benefits of Microservices Architecture? Chapter 7
  83. added 200 Data Durability Calculation Chapter 9
  84. added, gone 410 How Payment Gateways Can Detect and Prevent Online Fraud Chapter 11
  85. added, blocked 403 What is DDoS attack Chapter 11
  86. added, unreachable CME Co-Location and Data Center Services Chapter 13
  87. added 200 Cockroachdb Chapter 11
  88. added 200 Chain Services with Exactly-Once Guarantees Chapter 11
  89. added 200 Stripe API Reference Chapter 11
  90. added 200 Conversion rate: Definition Chapter 6
  91. added 200 Tipalti Chapter 11
  92. added 200 Consistent Hashing Chapter 5
  93. added, robots.txt A JSON Meta Application Protocol (JMAP) Subprotocol for WebSocket Chapter 8
  94. added 200 Kafka No Longer Requires ZooKeeper Chapter 4
  95. added, gone 404 Routing Tiles Chapter 3
  96. added, blocked 403 Akamai homepage Chapter 14
  97. added 200 Dynamo: Amazon's Highly Available Key-value Store Chapter 6
  98. added 200 Redis Pub/Sub Chapter 2
  99. added 200 Geekbang Chapter 10
  100. added 200 Stripe rate limiters Chapter 4
  101. added 200 Clickthrough rate (CTR): Definition Chapter 6
  102. added, blocked 403 Instacart Company engineering blogs
  103. added 200 Facebook Launches “Nearby Friends” Chapter 2
  104. added 200 29% Of Sites Face Duplicate Content Issues Chapter 9
  105. added, blocked 403 Zoom Company engineering blogs
  106. added 200 How fast is Redis? Chapter 10
  107. added 200 Flannel: An Application-Level Edge Cache to Make Slack Scale Chapter 12
  108. added, blocked 403 Why redis cluster only have 16384 slots Chapter 10
  109. added 200 Maglev - A Fast and Reliable Software Network Load Balancer Chapter 5
  110. added 200 Apache storm Chapter 13
  111. added 200 Stripe Company engineering blogs
  112. added, blocked 403 Geosharded Recommendations Part 1: Sharding Approach Chapter 1
  113. added 200 Info command Chapter 10
  114. added 200 S2 Chapter 1
  115. added 200 Email safety Chapter 8
  116. added 200 Sendgrid Chapter 10
  117. added 200 Slack Company engineering blogs
  118. added 200 Spark streaming Chapter 13
  119. added, blocked 403 How many leaves has a quadtree Chapter 1
  120. added 200 Bigtable: A Distributed Storage System for Structured Data Chapter 6
  121. added, blocked 403 Netflix Company engineering blogs
  122. added 200 Data model. : Chapter 5
  123. added 200 Redis GEOHASH Chapter 1
  124. added, gone 404 Leaderboards Chapter 10
  125. added 200 Dapper, a Large-Scale Distributed Systems Tracing Infrastructure Chapter 5
  126. added 200 How Many Emails Are Sent Per Day in 2021? Chapter 8
  127. added 200 RocksDB Chapter 12
  128. added 200 Kafka high watermark Chapter 4
  129. added, unreachable Region cover Chapter 1
  130. added 200 Erlang at Facebook (Facebook chat) Real-world systems
  131. added, blocked 403 Prototyping a Smoother Map Chapter 3
  132. added 200 Prometheus Chapter 5
  133. added 200 Designing for Understandability: the Raft Consensus Algorithm Chapter 13
  134. added 200 Reddit Company engineering blogs
  135. added 200 Redis Chapter 6
  136. added, blocked 403 Content Popularity for Open Connect Chapter 14
  137. added, robots.txt Message filtering in RocketMQdtree Chapter 4
  138. added, robots.txt Scheduled messages and delayed messages in Apache RocketMQ Chapter 4
  139. added 200 Grafana Demo Chapter 5
  140. added 200 POSTGIS Chapter 1
  141. added 200 Pull doesn’t scale - or does it? Chapter 5
  142. added 200 Raft Chapter 13
  143. added, blocked 403 Netflix Recommendations: Beyond the 5 stars (Part 2) Real-world systems
  144. added, blocked 403 Scaling Airbnb’s Payment Platform Chapter 11
  145. added 200 Monolithic Architecture Chapter 7
  146. added 200 Differential Synchronization Chapter 15
  147. added, robots.txt Flink performance tuning Chapter 6
  148. added 200 The Google File System (Google Docs) Real-world systems
  149. added, blocked 403 Airbnb Company engineering blogs
  150. added 200 memcached Chapter 6
  151. added 200 Saga Chapter 7
  152. added 200 Mixpanel Company engineering blogs
  153. added, blocked 403 Active-Active for Multi-Regional Resiliency Chapter 1
  154. added 200 Pinterest Architecture Update Real-world systems
  155. added 200 Event Sourcing Chapter 13
  156. added, blocked 403 Building real-time Leaderboard with Redis Chapter 10
  157. added 200 TAO: Facebook's Distributed Data Store for the Social Graph Real-world systems
  158. added 200 Kafka protocol guide Chapter 4
  159. added 200 CQRS Chapter 12
  160. added, blocked 403 System Design - Rate limiter and Data modelling Chapter 4
  161. added 200 Instagram Architecture: 14 Million Users, Terabytes Of Photos, 100s Of Instances, Dozens Of Technologies Real-world systems
  162. added 200 Push vs. pull Chapter 4
  163. added 200 mmap Chapter 12
  164. added, blocked 403 How We Built Prefixy: A Scalable Prefix Search Service for Powering Autocomplete Chapter 13
  165. added 200 Apache kafka Chapter 13
  166. added, blocked 403 How we created a real-time Leaderboard for a million Users Chapter 10
  167. added 200 Mailchimp Chapter 10
  168. added, gone 404 Redis Pub/Sub under the hood Chapter 2
  169. added 200 Blue green deployment Chapter 1
  170. added 200 Scaling Memcache at Facebook Real-world systems
  171. added 200 Kafka 2.0 Documentation Chapter 4
  172. added, blocked 403 Geohashing Chapter 3
  173. added 200 Spotify Company engineering blogs
  174. added 200 A 360 Degree View Of The Entire Netflix Stack Real-world systems
  175. added 200 Scaling Twitter: Making Twitter 10000 Percent Faster Real-world systems
  176. added, blocked 403 Shopify REST Admin API rate limits Chapter 4
  177. added 200 Optimistic and pessimistic record locking Chapter 7
  178. added 200 Apache James Chapter 8
  179. added 200 Apache Kafka Chapter 12
  180. added, blocked 429 How We've Scaled Dropbox Real-world systems
  181. added 200 HDFS Chapter 4
  182. added 200 Kappa architecture Chapter 6
  183. added 200 YouTube Architecture Real-world systems
  184. added 200 grpc Chapter 9
  185. added 200 Apache Hadoop Chapter 12
  186. added 200 Graphite Chapter 5
  187. added 200 Scaling Pinterest Real-world systems
  188. added 200 How Uber Scales Their Real-Time Market Platform Real-world systems
  189. added 200 Amazon Architecture Real-world systems
  190. added, blocked 403 Announcing Snowflake (Snowflake is a network service for generating unique ID numbers at high scale with some simple guarantees) Real-world systems
  191. added 200 Facebook Timeline: Brought To You By The Power Of Denormalization Real-world systems
  192. added 200 The Architecture Twitter Uses To Deal With 150M Active Users Real-world systems
  193. added 200 Finding a needle in Haystack: Facebook's photo storage Real-world systems
  194. added 200 Flickr Architecture Real-world systems
  195. added, blocked 403 Groupon Company engineering blogs
  196. added 200 Google Architecture Real-world systems
  197. added, blocked 429 Seattle Conference on Scalability: YouTube Scalability Real-world systems
  198. added 200 Dynamo: Amazon's Highly Available Key-value Store Real-world systems
  199. added, blocked 403 It's All A/Bout Testing: The Netflix Experimentation Platform Real-world systems
  200. added 200 Serving Facebook Multifeed: Efficiency, performance gains through redesign Real-world systems