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@@ -893,7 +893,7 @@ You'll get more graph practice in Skiena's book (see Books section below) and th
         - [x] Pragmatic Programming Techniques: http://horicky.blogspot.com/2010/10/scalable-system-design-patterns.html
             - extra: Google Pregel Graph Processing: http://horicky.blogspot.com/2010/07/google-pregel-graph-processing.html
         - [x] Jeff Dean - Building Software Systems At Google and Lessons Learned: https://www.youtube.com/watch?v=modXC5IWTJI
-        - [ ] Introduction to Architecting Systems for Scale: http://lethain.com/introduction-to-architecting-systems-for-scale/
+        - [x] Introduction to Architecting Systems for Scale: http://lethain.com/introduction-to-architecting-systems-for-scale/
         - [x] Scaling mobile games to a global audience using App Engine and Cloud Datastore: https://www.youtube.com/watch?v=9nWyWwY2Onc
         - [x] How Google Does Planet-Scale Engineering for Planet-Scale Infra: https://www.youtube.com/watch?v=H4vMcD7zKM0
         - [x] The Importance of Algorithms: https://www.topcoder.com/community/data-science/data-science-tutorials/the-importance-of-algorithms/