{"type":"excalidraw","version":2,"source":"https://AwesomeSystemDesign.dev","elements":[{"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-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":16,"y":16,"width":288,"height":121.8,"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":36,"y":34,"width":248,"height":85.8,"fontSize":22,"fontFamily":1,"text":"Cart stored in Redis\n(not SQL) for speed\nand session handling","originalText":"Cart stored in Redis\n(not SQL) for speed\nand session handling","textAlign":"left","verticalAlign":"middle","containerId":"shape-0","lineHeight":1.3,"autoResize":false,"customData":{"revealStep":1}},{"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-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":16,"y":181.8,"width":288,"height":179,"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":36,"y":199.8,"width":248,"height":143,"fontSize":22,"fontFamily":1,"text":"Key: cart:{user_id}\nType: Hash\nTTL: 30 days\n(abandoned cart\ncleanup)","originalText":"Key: cart:{user_id}\nType: Hash\nTTL: 30 days\n(abandoned cart\ncleanup)","textAlign":"left","verticalAlign":"middle","containerId":"shape-2","lineHeight":1.3,"autoResize":false,"customData":{"revealStep":2}},{"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-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":16,"y":404.8,"width":288,"height":264.8,"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":36,"y":422.8,"width":248,"height":228.8,"fontSize":22,"fontFamily":1,"text":"HSET cart:user123\nSKU-BLK-001\n'{\"qty\":2,\"price\":7999,\"\nadded\":\"...\"}'\nHSET cart:user123\nSKU-RED-003\n'{\"qty\":1,\"price\":4999,\"\nadded\":\"...\"}'","originalText":"HSET cart:user123\nSKU-BLK-001\n'{\"qty\":2,\"price\":7999,\"\nadded\":\"...\"}'\nHSET cart:user123\nSKU-RED-003\n'{\"qty\":1,\"price\":4999,\"\nadded\":\"...\"}'","textAlign":"left","verticalAlign":"middle","containerId":"shape-4","lineHeight":1.3,"autoResize":false,"customData":{"revealStep":3}},{"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-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":16,"y":713.6,"width":288,"height":207.6,"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":36,"y":731.6,"width":248,"height":171.6,"fontSize":22,"fontFamily":1,"text":"HGETALL\ncart:user123 → all\nitems\nHDEL cart:user123\nSKU-RED-003 →\nremove item","originalText":"HGETALL\ncart:user123 → all\nitems\nHDEL cart:user123\nSKU-RED-003 →\nremove item","textAlign":"left","verticalAlign":"middle","containerId":"shape-6","lineHeight":1.3,"autoResize":false,"customData":{"revealStep":4}},{"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-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":16,"y":965.2,"width":288,"height":465,"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":36,"y":983.2,"width":248,"height":429,"fontSize":22,"fontFamily":1,"text":"Why Redis not SQL:\n• Cart is temporary,\nhigh-churn data\n• Accessed every\npage load (cart\nbadge count)\n• 100M DAU × avg 3\ncart items = 300M\nentries (fits in ~100\nGB)\n• Sub-ms reads\ncritical for page load\ntime\n• Abandoned carts\nauto-expire (TTL)","originalText":"Why Redis not SQL:\n• Cart is temporary,\nhigh-churn data\n• Accessed every\npage load (cart\nbadge count)\n• 100M DAU × avg 3\ncart items = 300M\nentries (fits in ~100\nGB)\n• Sub-ms reads\ncritical for page load\ntime\n• Abandoned carts\nauto-expire (TTL)","textAlign":"left","verticalAlign":"middle","containerId":"shape-8","lineHeight":1.3,"autoResize":false,"customData":{"revealStep":5}}],"appState":{"viewBackgroundColor":"#fbfbf8","gridSize":null},"files":{}}