{"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":550.8000000000001,"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":514.8000000000001,"fontSize":22,"fontFamily":1,"text":"Simple\nreverse-chronological\nfeed of people you\nfollow. No algorithmic\nranking.\n\nImplementation:\n- Pure\nfanout-on-write (with\nhybrid for celebs)\n- Redis sorted set\nby timestamp\n- No ML ranking\nneeded\n- Filter: remove\nmuted users, blocked\ncontent\n- Simple and fast","originalText":"Simple\nreverse-chronological\nfeed of people you\nfollow. No algorithmic\nranking.\n\nImplementation:\n- Pure\nfanout-on-write (with\nhybrid for celebs)\n- Redis sorted set\nby timestamp\n- No ML ranking\nneeded\n- Filter: remove\nmuted users, blocked\ncontent\n- Simple and fast","textAlign":"left","verticalAlign":"middle","containerId":"shape-0","lineHeight":1.3,"autoResize":false,"customData":{"revealStep":1}},{"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-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":610.8000000000001,"width":288,"height":1494.6000000000001,"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":628.8000000000001,"width":248,"height":1458.6000000000001,"fontSize":22,"fontFamily":1,"text":"Personalized, ranked\nfeed mixing:\n- In-network (people\nyou follow): ~50%\n- Out-of-network\n(recommended): ~50%\n\nOut-of-network\nsources:\n- Posts\nliked/retweeted by\npeople you follow\n- Posts from similar\nusers (embedding\nsimilarity)\n- Trending content in\nyour interest\nclusters\n- Content from\naccounts you've\ninteracted with\nbut don't follow\n\nSimClusters\n(Twitter's approach):\n- Group users into\n~150K interest\nclusters\n- Each user belongs\nto multiple clusters\n- Each tweet is\nscored against\nrelevant clusters\n- Recommend tweets\nthat score high in\nuser's\nclusters but weren't\nin their in-network\nfeed\n\nCandidate sourcing:\n- In-network: 500\nfrom feed cache\n- Out-of-network:\n500 from\nSimClusters + social\nproof (friends liked\nthis tweet)\n- Total: ~1000\ncandidates -> rank\n-> top 20","originalText":"Personalized, ranked\nfeed mixing:\n- In-network (people\nyou follow): ~50%\n- Out-of-network\n(recommended): ~50%\n\nOut-of-network\nsources:\n- Posts\nliked/retweeted by\npeople you follow\n- Posts from similar\nusers (embedding\nsimilarity)\n- Trending content in\nyour interest\nclusters\n- Content from\naccounts you've\ninteracted with\nbut don't follow\n\nSimClusters\n(Twitter's approach):\n- Group users into\n~150K interest\nclusters\n- Each user belongs\nto multiple clusters\n- Each tweet is\nscored against\nrelevant clusters\n- Recommend tweets\nthat score high in\nuser's\nclusters but weren't\nin their in-network\nfeed\n\nCandidate sourcing:\n- In-network: 500\nfrom feed cache\n- Out-of-network:\n500 from\nSimClusters + social\nproof (friends liked\nthis tweet)\n- Total: ~1000\ncandidates -> rank\n-> top 20","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":2149.4,"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":2167.4,"width":248,"height":228.8,"fontSize":22,"fontFamily":1,"text":"Twitter's Two\nTimeline Modes\n\n\"Following\" tab\n(chronological):\n\n\"For You\" tab\n(algorithmic):","originalText":"Twitter's Two\nTimeline Modes\n\n\"Following\" tab\n(chronological):\n\n\"For You\" tab\n(algorithmic):","textAlign":"left","verticalAlign":"middle","containerId":"shape-4","lineHeight":1.3,"autoResize":false,"customData":{"revealStep":3}}],"appState":{"viewBackgroundColor":"#fbfbf8","gridSize":null},"files":{}}