{"type":"excalidraw","version":2,"source":"https://AwesomeSystemDesign.dev","elements":[{"angle":0,"strokeColor":"#628572","backgroundColor":"#edf5ee","fillStyle":"solid","strokeWidth":1.5,"strokeStyle":"solid","roughness":0.7,"opacity":100,"version":1,"versionNonce":1,"isDeleted":false,"groupIds":["step-1"],"frameId":null,"roundness":null,"boundElements":[{"type":"text","id":"shape-1"}],"updated":0,"link":null,"locked":false,"id":"shape-0","type":"rectangle","seed":41,"x":30,"y":30,"width":420,"height":68,"customData":{"revealStep":1}},{"angle":0,"strokeColor":"#394557","backgroundColor":"transparent","fillStyle":"solid","strokeWidth":1.5,"strokeStyle":"solid","roughness":0.7,"opacity":100,"version":1,"versionNonce":1,"isDeleted":false,"groupIds":["step-1"],"frameId":null,"roundness":null,"boundElements":null,"updated":0,"link":null,"locked":false,"id":"shape-1","type":"text","seed":114,"x":50,"y":52.3,"width":380,"height":23.400000000000002,"fontSize":18,"fontFamily":1,"text":"Stream Database Changes as Events","originalText":"Stream Database Changes as Events","textAlign":"left","verticalAlign":"middle","containerId":"shape-0","lineHeight":1.3,"autoResize":false,"customData":{"revealStep":1}},{"angle":0,"strokeColor":"#a68a53","backgroundColor":"#fff7e6","fillStyle":"solid","strokeWidth":1.5,"strokeStyle":"solid","roughness":0.7,"opacity":100,"version":1,"versionNonce":1,"isDeleted":false,"groupIds":["step-2"],"frameId":null,"roundness":null,"boundElements":[{"type":"text","id":"shape-3"}],"updated":0,"link":null,"locked":false,"id":"shape-2","type":"rectangle","seed":187,"x":30,"y":123,"width":577.63624,"height":106.2,"customData":{"revealStep":2}},{"angle":0,"strokeColor":"#394557","backgroundColor":"transparent","fillStyle":"solid","strokeWidth":1.5,"strokeStyle":"solid","roughness":0.7,"opacity":100,"version":1,"versionNonce":1,"isDeleted":false,"groupIds":["step-2"],"frameId":null,"roundness":null,"boundElements":null,"updated":0,"link":null,"locked":false,"id":"shape-3","type":"text","seed":260,"x":50,"y":141,"width":537.63624,"height":70.2,"fontSize":18,"fontFamily":1,"text":"Problem: Legacy service writes to PostgreSQL via CRUD.\nOther services need to react to those changes.\nCan't modify legacy service to publish events.","originalText":"Problem: Legacy service writes to PostgreSQL via CRUD.\nOther services need to react to those changes.\nCan't modify legacy service to publish events.","textAlign":"left","verticalAlign":"middle","containerId":"shape-2","lineHeight":1.3,"autoResize":false,"customData":{"revealStep":2}},{"angle":0,"strokeColor":"#9180ac","backgroundColor":"#f4effb","fillStyle":"solid","strokeWidth":1.5,"strokeStyle":"solid","roughness":0.7,"opacity":100,"version":1,"versionNonce":1,"isDeleted":false,"groupIds":["step-3"],"frameId":null,"roundness":null,"boundElements":[{"type":"text","id":"shape-5"}],"updated":0,"link":null,"locked":false,"id":"shape-4","type":"rectangle","seed":333,"x":30,"y":254.2,"width":655.17736,"height":82.80000000000001,"customData":{"revealStep":3}},{"angle":0,"strokeColor":"#394557","backgroundColor":"transparent","fillStyle":"solid","strokeWidth":1.5,"strokeStyle":"solid","roughness":0.7,"opacity":100,"version":1,"versionNonce":1,"isDeleted":false,"groupIds":["step-3"],"frameId":null,"roundness":null,"boundElements":null,"updated":0,"link":null,"locked":false,"id":"shape-5","type":"text","seed":406,"x":50,"y":272.2,"width":615.17736,"height":46.800000000000004,"fontSize":18,"fontFamily":1,"text":"Solution: CDC reads the database's transaction log (WAL/binlog)\nand publishes each change as an event.","originalText":"Solution: CDC reads the database's transaction log (WAL/binlog)\nand publishes each change as an event.","textAlign":"left","verticalAlign":"middle","containerId":"shape-4","lineHeight":1.3,"autoResize":false,"customData":{"revealStep":3}},{"angle":0,"strokeColor":"#6577aa","backgroundColor":"#eef1fc","fillStyle":"solid","strokeWidth":1.5,"strokeStyle":"solid","roughness":0.7,"opacity":100,"version":1,"versionNonce":1,"isDeleted":false,"groupIds":["step-4"],"frameId":null,"roundness":null,"boundElements":[{"type":"text","id":"shape-7"}],"updated":0,"link":null,"locked":false,"id":"shape-6","type":"rectangle","seed":479,"x":30,"y":362,"width":458.5579600000001,"height":68,"customData":{"revealStep":4}},{"angle":0,"strokeColor":"#394557","backgroundColor":"transparent","fillStyle":"solid","strokeWidth":1.5,"strokeStyle":"solid","roughness":0.7,"opacity":100,"version":1,"versionNonce":1,"isDeleted":false,"groupIds":["step-4"],"frameId":null,"roundness":null,"boundElements":null,"updated":0,"link":null,"locked":false,"id":"shape-7","type":"text","seed":552,"x":50,"y":384.3,"width":418.5579600000001,"height":23.400000000000002,"fontSize":18,"fontFamily":1,"text":"PostgreSQL WAL Debezium Kafka Consumers","originalText":"PostgreSQL WAL Debezium Kafka Consumers","textAlign":"left","verticalAlign":"middle","containerId":"shape-6","lineHeight":1.3,"autoResize":false,"customData":{"revealStep":4}},{"angle":0,"strokeColor":"#628572","backgroundColor":"#edf5ee","fillStyle":"solid","strokeWidth":1.5,"strokeStyle":"solid","roughness":0.7,"opacity":100,"version":1,"versionNonce":1,"isDeleted":false,"groupIds":["step-5"],"frameId":null,"roundness":null,"boundElements":[{"type":"text","id":"shape-9"}],"updated":0,"link":null,"locked":false,"id":"shape-8","type":"rectangle","seed":625,"x":30,"y":455,"width":420,"height":106.2,"customData":{"revealStep":5}},{"angle":0,"strokeColor":"#394557","backgroundColor":"transparent","fillStyle":"solid","strokeWidth":1.5,"strokeStyle":"solid","roughness":0.7,"opacity":100,"version":1,"versionNonce":1,"isDeleted":false,"groupIds":["step-5"],"frameId":null,"roundness":null,"boundElements":null,"updated":0,"link":null,"locked":false,"id":"shape-9","type":"text","seed":698,"x":50,"y":473,"width":380,"height":70.2,"fontSize":18,"fontFamily":1,"text":"INSERT order -------->\nUPDATE order -------->\nDELETE order -------->","originalText":"INSERT order -------->\nUPDATE order -------->\nDELETE order -------->","textAlign":"left","verticalAlign":"middle","containerId":"shape-8","lineHeight":1.3,"autoResize":false,"customData":{"revealStep":5}},{"angle":0,"strokeColor":"#a68a53","backgroundColor":"#fff7e6","fillStyle":"solid","strokeWidth":1.5,"strokeStyle":"solid","roughness":0.7,"opacity":100,"version":1,"versionNonce":1,"isDeleted":false,"groupIds":["step-6"],"frameId":null,"roundness":null,"boundElements":[{"type":"text","id":"shape-11"}],"updated":0,"link":null,"locked":false,"id":"shape-10","type":"rectangle","seed":771,"x":30,"y":586.2,"width":420,"height":68,"customData":{"revealStep":6}},{"angle":0,"strokeColor":"#394557","backgroundColor":"transparent","fillStyle":"solid","strokeWidth":1.5,"strokeStyle":"solid","roughness":0.7,"opacity":100,"version":1,"versionNonce":1,"isDeleted":false,"groupIds":["step-6"],"frameId":null,"roundness":null,"boundElements":null,"updated":0,"link":null,"locked":false,"id":"shape-11","type":"text","seed":844,"x":50,"y":608.5,"width":380,"height":23.400000000000002,"fontSize":18,"fontFamily":1,"text":"Read WAL/replication","originalText":"Read WAL/replication","textAlign":"left","verticalAlign":"middle","containerId":"shape-10","lineHeight":1.3,"autoResize":false,"customData":{"revealStep":6}},{"angle":0,"strokeColor":"#9180ac","backgroundColor":"#f4effb","fillStyle":"solid","strokeWidth":1.5,"strokeStyle":"solid","roughness":0.7,"opacity":100,"version":1,"versionNonce":1,"isDeleted":false,"groupIds":["step-7"],"frameId":null,"roundness":null,"boundElements":[{"type":"text","id":"shape-13"}],"updated":0,"link":null,"locked":false,"id":"shape-12","type":"rectangle","seed":917,"x":30,"y":679.2,"width":420,"height":106.2,"customData":{"revealStep":7}},{"angle":0,"strokeColor":"#394557","backgroundColor":"transparent","fillStyle":"solid","strokeWidth":1.5,"strokeStyle":"solid","roughness":0.7,"opacity":100,"version":1,"versionNonce":1,"isDeleted":false,"groupIds":["step-7"],"frameId":null,"roundness":null,"boundElements":null,"updated":0,"link":null,"locked":false,"id":"shape-13","type":"text","seed":990,"x":50,"y":697.2,"width":380,"height":70.2,"fontSize":18,"fontFamily":1,"text":"publish ---->\ntopic:\ndb.orders","originalText":"publish ---->\ntopic:\ndb.orders","textAlign":"left","verticalAlign":"middle","containerId":"shape-12","lineHeight":1.3,"autoResize":false,"customData":{"revealStep":7}},{"angle":0,"strokeColor":"#6577aa","backgroundColor":"#eef1fc","fillStyle":"solid","strokeWidth":1.5,"strokeStyle":"solid","roughness":0.7,"opacity":100,"version":1,"versionNonce":1,"isDeleted":false,"groupIds":["step-8"],"frameId":null,"roundness":null,"boundElements":[{"type":"text","id":"shape-15"}],"updated":0,"link":null,"locked":false,"id":"shape-14","type":"rectangle","seed":1063,"x":30,"y":810.4000000000001,"width":420,"height":106.2,"customData":{"revealStep":8}},{"angle":0,"strokeColor":"#394557","backgroundColor":"transparent","fillStyle":"solid","strokeWidth":1.5,"strokeStyle":"solid","roughness":0.7,"opacity":100,"version":1,"versionNonce":1,"isDeleted":false,"groupIds":["step-8"],"frameId":null,"roundness":null,"boundElements":null,"updated":0,"link":null,"locked":false,"id":"shape-15","type":"text","seed":1136,"x":50,"y":828.4000000000001,"width":380,"height":70.2,"fontSize":18,"fontFamily":1,"text":"\"op\":\"c\", · (c=create,\n\"before\":null · u=update,\n\"after\":{...} · d=delete)","originalText":"\"op\":\"c\", · (c=create,\n\"before\":null · u=update,\n\"after\":{...} · d=delete)","textAlign":"left","verticalAlign":"middle","containerId":"shape-14","lineHeight":1.3,"autoResize":false,"customData":{"revealStep":8}},{"angle":0,"strokeColor":"#628572","backgroundColor":"#edf5ee","fillStyle":"solid","strokeWidth":1.5,"strokeStyle":"solid","roughness":0.7,"opacity":100,"version":1,"versionNonce":1,"isDeleted":false,"groupIds":["step-9"],"frameId":null,"roundness":null,"boundElements":[{"type":"text","id":"shape-17"}],"updated":0,"link":null,"locked":false,"id":"shape-16","type":"rectangle","seed":1209,"x":30,"y":941.6000000000001,"width":420,"height":68,"customData":{"revealStep":9}},{"angle":0,"strokeColor":"#394557","backgroundColor":"transparent","fillStyle":"solid","strokeWidth":1.5,"strokeStyle":"solid","roughness":0.7,"opacity":100,"version":1,"versionNonce":1,"isDeleted":false,"groupIds":["step-9"],"frameId":null,"roundness":null,"boundElements":null,"updated":0,"link":null,"locked":false,"id":"shape-17","type":"text","seed":1282,"x":50,"y":963.9000000000001,"width":380,"height":23.400000000000002,"fontSize":18,"fontFamily":1,"text":"consume -------->","originalText":"consume -------->","textAlign":"left","verticalAlign":"middle","containerId":"shape-16","lineHeight":1.3,"autoResize":false,"customData":{"revealStep":9}},{"angle":0,"strokeColor":"#a68a53","backgroundColor":"#fff7e6","fillStyle":"solid","strokeWidth":1.5,"strokeStyle":"solid","roughness":0.7,"opacity":100,"version":1,"versionNonce":1,"isDeleted":false,"groupIds":["step-10"],"frameId":null,"roundness":null,"boundElements":[{"type":"text","id":"shape-19"}],"updated":0,"link":null,"locked":false,"id":"shape-18","type":"rectangle","seed":1355,"x":30,"y":1034.6000000000001,"width":420,"height":82.80000000000001,"customData":{"revealStep":10}},{"angle":0,"strokeColor":"#394557","backgroundColor":"transparent","fillStyle":"solid","strokeWidth":1.5,"strokeStyle":"solid","roughness":0.7,"opacity":100,"version":1,"versionNonce":1,"isDeleted":false,"groupIds":["step-10"],"frameId":null,"roundness":null,"boundElements":null,"updated":0,"link":null,"locked":false,"id":"shape-19","type":"text","seed":1428,"x":50,"y":1052.6000000000001,"width":380,"height":46.800000000000004,"fontSize":18,"fontFamily":1,"text":"Search indexer:\nupdate Elasticsearch","originalText":"Search indexer:\nupdate Elasticsearch","textAlign":"left","verticalAlign":"middle","containerId":"shape-18","lineHeight":1.3,"autoResize":false,"customData":{"revealStep":10}},{"angle":0,"strokeColor":"#9180ac","backgroundColor":"#f4effb","fillStyle":"solid","strokeWidth":1.5,"strokeStyle":"solid","roughness":0.7,"opacity":100,"version":1,"versionNonce":1,"isDeleted":false,"groupIds":["step-11"],"frameId":null,"roundness":null,"boundElements":[{"type":"text","id":"shape-21"}],"updated":0,"link":null,"locked":false,"id":"shape-20","type":"rectangle","seed":1501,"x":30,"y":1142.4,"width":420,"height":82.80000000000001,"customData":{"revealStep":11}},{"angle":0,"strokeColor":"#394557","backgroundColor":"transparent","fillStyle":"solid","strokeWidth":1.5,"strokeStyle":"solid","roughness":0.7,"opacity":100,"version":1,"versionNonce":1,"isDeleted":false,"groupIds":["step-11"],"frameId":null,"roundness":null,"boundElements":null,"updated":0,"link":null,"locked":false,"id":"shape-21","type":"text","seed":1574,"x":50,"y":1160.4,"width":380,"height":46.800000000000004,"fontSize":18,"fontFamily":1,"text":"Cache invalidator:\nevict from Redis","originalText":"Cache invalidator:\nevict from Redis","textAlign":"left","verticalAlign":"middle","containerId":"shape-20","lineHeight":1.3,"autoResize":false,"customData":{"revealStep":11}},{"angle":0,"strokeColor":"#6577aa","backgroundColor":"#eef1fc","fillStyle":"solid","strokeWidth":1.5,"strokeStyle":"solid","roughness":0.7,"opacity":100,"version":1,"versionNonce":1,"isDeleted":false,"groupIds":["step-12"],"frameId":null,"roundness":null,"boundElements":[{"type":"text","id":"shape-23"}],"updated":0,"link":null,"locked":false,"id":"shape-22","type":"rectangle","seed":1647,"x":30,"y":1250.2,"width":420,"height":82.80000000000001,"customData":{"revealStep":12}},{"angle":0,"strokeColor":"#394557","backgroundColor":"transparent","fillStyle":"solid","strokeWidth":1.5,"strokeStyle":"solid","roughness":0.7,"opacity":100,"version":1,"versionNonce":1,"isDeleted":false,"groupIds":["step-12"],"frameId":null,"roundness":null,"boundElements":null,"updated":0,"link":null,"locked":false,"id":"shape-23","type":"text","seed":1720,"x":50,"y":1268.2,"width":380,"height":46.800000000000004,"fontSize":18,"fontFamily":1,"text":"Data warehouse:\nreplicate to BQ","originalText":"Data warehouse:\nreplicate to BQ","textAlign":"left","verticalAlign":"middle","containerId":"shape-22","lineHeight":1.3,"autoResize":false,"customData":{"revealStep":12}},{"angle":0,"strokeColor":"#628572","backgroundColor":"#edf5ee","fillStyle":"solid","strokeWidth":1.5,"strokeStyle":"solid","roughness":0.7,"opacity":100,"version":1,"versionNonce":1,"isDeleted":false,"groupIds":["step-13"],"frameId":null,"roundness":null,"boundElements":[{"type":"text","id":"shape-25"}],"updated":0,"link":null,"locked":false,"id":"shape-24","type":"rectangle","seed":1793,"x":30,"y":1358,"width":524.4412,"height":176.4,"customData":{"revealStep":13}},{"angle":0,"strokeColor":"#394557","backgroundColor":"transparent","fillStyle":"solid","strokeWidth":1.5,"strokeStyle":"solid","roughness":0.7,"opacity":100,"version":1,"versionNonce":1,"isDeleted":false,"groupIds":["step-13"],"frameId":null,"roundness":null,"boundElements":null,"updated":0,"link":null,"locked":false,"id":"shape-25","type":"text","seed":1866,"x":50,"y":1376,"width":484.4412,"height":140.4,"fontSize":18,"fontFamily":1,"text":"Benefits:\n✅ No application code changes needed\n✅ Captures ALL changes (even direct SQL updates)\n✅ Low overhead (reads log, doesn't poll table)\n✅ Preserves ordering (log is ordered)\n✅ Can replay from any point in WAL","originalText":"Benefits:\n✅ No application code changes needed\n✅ Captures ALL changes (even direct SQL updates)\n✅ Low overhead (reads log, doesn't poll table)\n✅ Preserves ordering (log is ordered)\n✅ Can replay from any point in WAL","textAlign":"left","verticalAlign":"middle","containerId":"shape-24","lineHeight":1.3,"autoResize":false,"customData":{"revealStep":13}},{"angle":0,"strokeColor":"#a68a53","backgroundColor":"#fff7e6","fillStyle":"solid","strokeWidth":1.5,"strokeStyle":"solid","roughness":0.7,"opacity":100,"version":1,"versionNonce":1,"isDeleted":false,"groupIds":["step-14"],"frameId":null,"roundness":null,"boundElements":[{"type":"text","id":"shape-27"}],"updated":0,"link":null,"locked":false,"id":"shape-26","type":"rectangle","seed":1939,"x":30,"y":1559.4,"width":629.01868,"height":153,"customData":{"revealStep":14}},{"angle":0,"strokeColor":"#394557","backgroundColor":"transparent","fillStyle":"solid","strokeWidth":1.5,"strokeStyle":"solid","roughness":0.7,"opacity":100,"version":1,"versionNonce":1,"isDeleted":false,"groupIds":["step-14"],"frameId":null,"roundness":null,"boundElements":null,"updated":0,"link":null,"locked":false,"id":"shape-27","type":"text","seed":2012,"x":50,"y":1577.4,"width":589.01868,"height":117,"fontSize":18,"fontFamily":1,"text":"Pitfalls:\n❌ Schema changes in source DB affect CDC events\n❌ Log-based CDC requires DB replication slot (PostgreSQL)\n❌ Large initial snapshot for existing data\n❌ Debezium connector can fall behind on high-throughput tables","originalText":"Pitfalls:\n❌ Schema changes in source DB affect CDC events\n❌ Log-based CDC requires DB replication slot (PostgreSQL)\n❌ Large initial snapshot for existing data\n❌ Debezium connector can fall behind on high-throughput tables","textAlign":"left","verticalAlign":"middle","containerId":"shape-26","lineHeight":1.3,"autoResize":false,"customData":{"revealStep":14}}],"appState":{"viewBackgroundColor":"#fbfbf8","gridSize":null},"files":{}}