System Design AI

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Classic designs 4

Ordered by design number

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39. Design a Calendar System
Google Calendar-style events with recurrence, RSVPs and on-time reminders, using CDC for change notifications and a delay queue for reminders.
ClassicMedium
Caching Queues Databases
+5
Calendar Change data capture Notifications PostgreSQL Scheduling
Worked design
Practice
56. Design a Local Business Review Site like Yelp
Search 10 million businesses by place, words and category, keep every average rating exact, and keep fake reviews out.
ClassicMedium
Databases Search AWS
+5
Change data capture Geospatial OpenSearch PostgreSQL Reviews
Worked design
Practice
76. Design a Relational Database like PostgreSQL
A relational database like PostgreSQL: WAL and MVCC on one server, quorum replication and failover, then a sharded fleet.
ClassicMedium
Databases Distributed systems Aurora
+5
AWS MVCC PostgreSQL Relational Replication
Worked design
Practice
85. Design a Change Data Capture Pipeline
Every committed change in Aurora and DynamoDB, read from the log and delivered in order per row to search, caches, Redshift and an S3 lake.
ClassicMedium
Queues Databases Streaming
+8
Transactions Distributed systems AWS Change data capture Debezium Kafka Outbox PostgreSQL
Worked design
Practice

Each design brings together the brief, practice, examples and discussion.