[{"data":1,"prerenderedAt":1309},["ShallowReactive",2],{"content:\u002Fjavascript-bundle-optimization-code-splitting\u002Fdynamic-imports-and-route-based-splitting\u002Fimplementing-route-level-code-splitting-in-nextjs\u002F":3,"surroundings:\u002Fjavascript-bundle-optimization-code-splitting\u002Fdynamic-imports-and-route-based-splitting\u002Fimplementing-route-level-code-splitting-in-nextjs\u002F":1300},{"id":4,"title":5,"body":6,"description":1293,"extension":1294,"meta":1295,"navigation":204,"path":1296,"seo":1297,"stem":1298,"__hash__":1299},"content\u002Fjavascript-bundle-optimization-code-splitting\u002Fdynamic-imports-and-route-based-splitting\u002Fimplementing-route-level-code-splitting-in-nextjs\u002Findex.md","Implementing Route-Level Code Splitting in Next.js: Diagnostic & Configuration Guide",{"type":7,"value":8,"toc":1278},"minimark",[9,13,23,28,31,66,78,82,85,104,131,141,145,150,160,343,347,353,542,549,555,1067,1071,1074,1118,1122,1125,1155,1159,1223,1227,1233,1239,1255,1274],[10,11,5],"h1",{"id":12},"implementing-route-level-code-splitting-in-nextjs-diagnostic-configuration-guide",[14,15,16,17,22],"p",{},"Route-level code splitting is foundational to ",[18,19,21],"a",{"href":20},"\u002Fjavascript-bundle-optimization-code-splitting\u002F","JavaScript Bundle Optimization & Code Splitting",", yet many Next.js deployments suffer from degraded FCP and TTI due to misconfigured chunk boundaries. This guide targets a specific regression: monolithic route bundles caused by improper barrel exports, missing dynamic boundaries, or overridden webpack defaults. We will diagnose exact failure points using DevTools Network and Lighthouse, apply precise configuration fixes, and validate against strict performance thresholds.",[24,25,27],"h2",{"id":26},"root-cause-analysis-why-route-splitting-fails-in-nextjs","Root Cause Analysis: Why Route Splitting Fails in Next.js",[14,29,30],{},"Route splitting degrades when webpack cannot isolate dependency graphs. Three primary failure modes dominate production regressions:",[32,33,34,42,56],"ul",{},[35,36,37,41],"li",{},[38,39,40],"strong",{},"Barrel\u002Findex file imports"," force webpack to bundle entire component trees into a single chunk.",[35,43,44,51,52,55],{},[38,45,46,50],{},[47,48,49],"code",{},"next.config.js"," overrides"," that inadvertently disable automatic route splitting or misconfigure ",[47,53,54],{},"splitChunks",".",[35,57,58,65],{},[38,59,60,61,64],{},"Improper ",[47,62,63],{},"next\u002Fdynamic"," usage"," triggering synchronous hydration instead of deferred loading.",[14,67,68,69,73,74,77],{},"Next.js App Router handles route boundaries automatically by default. The Pages Router requires explicit configuration to maintain isolation. For architectural context on how module graphs resolve across boundaries, refer to ",[18,70,72],{"href":71},"\u002Fjavascript-bundle-optimization-code-splitting\u002Fdynamic-imports-and-route-based-splitting\u002F","Dynamic Imports and Route-Based Splitting",". Misaligned boundaries typically manifest as a single ",[47,75,76],{},"main.js"," payload exceeding 300KB on initial load.",[24,79,81],{"id":80},"diagnostic-workflow-devtools-lighthouse-thresholds","Diagnostic Workflow: DevTools & Lighthouse Thresholds",[14,83,84],{},"Isolate route bundle bloat using this reproducible diagnostic sequence:",[86,87,88,95,98,101],"ol",{},[35,89,90,91,94],{},"Open Chrome DevTools > Network tab. Filter by ",[47,92,93],{},"JS",". Disable cache.",[35,96,97],{},"Trigger a hard reload. Identify chunks blocking FCP. Flag any single route chunk > 150KB.",[35,99,100],{},"Run Lighthouse > Performance tab. Capture TTI and TBT metrics.",[35,102,103],{},"Validate against strict engineering thresholds:",[32,105,106,113,119,125],{},[35,107,108,109,112],{},"Initial JS payload per route: ",[47,110,111],{},"\u003C 150KB"," (minified + gzipped)",[35,114,115,116],{},"FCP: ",[47,117,118],{},"\u003C 1.8s",[35,120,121,122],{},"TTI: ",[47,123,124],{},"\u003C 2.5s",[35,126,127,128],{},"Cross-route chunk overlap: ",[47,129,130],{},"\u003C 20%",[86,132,134],{"start":133},5,[35,135,136,137,140],{},"Use the Coverage tab (",[47,138,139],{},"Ctrl+Shift+P"," > \"Show Coverage\"). Record unused bytes. High coverage on route-specific imports indicates dead code masking as active dependencies.",[24,142,144],{"id":143},"step-by-step-implementation-configuring-route-level-splits","Step-by-Step Implementation: Configuring Route-Level Splits",[146,147,149],"h3",{"id":148},"pages-router-configuration","Pages Router Configuration",[14,151,152,153,155,156,159],{},"Use ",[47,154,63],{}," with explicit loading states to defer non-critical UI. Avoid ",[47,157,158],{},"ssr: false"," unless strictly necessary.",[161,162,167],"pre",{"className":163,"code":164,"language":165,"meta":166,"style":166},"language-javascript shiki shiki-themes github-dark-high-contrast github-dark-high-contrast github-light-high-contrast","\u002F\u002F pages\u002Fdashboard.tsx\nimport dynamic from 'next\u002Fdynamic';\n\nconst HeavyWidget = dynamic(() => import('..\u002Fcomponents\u002FHeavyWidget'), {\n loading: () => \u003Cdiv className=\"skeleton\">Loading module...\u003C\u002Fdiv>,\n ssr: false, \u002F\u002F Reserve strictly for browser-only APIs\n});\n\nexport default function Dashboard() {\n return \u003CHeavyWidget \u002F>;\n}\n","javascript","",[47,168,169,178,199,206,241,275,290,296,301,323,337],{"__ignoreMap":166},[170,171,174],"span",{"class":172,"line":173},"line",1,[170,175,177],{"class":176},"sXJMR","\u002F\u002F pages\u002Fdashboard.tsx\n",[170,179,181,185,189,192,196],{"class":172,"line":180},2,[170,182,184],{"class":183},"sCJTb","import",[170,186,188],{"class":187},"s3sCt"," dynamic ",[170,190,191],{"class":183},"from",[170,193,195],{"class":194},"sJdzJ"," 'next\u002Fdynamic'",[170,197,198],{"class":187},";\n",[170,200,202],{"class":172,"line":201},3,[170,203,205],{"emptyLinePlaceholder":204},true,"\n",[170,207,209,212,216,219,223,226,229,232,235,238],{"class":172,"line":208},4,[170,210,211],{"class":183},"const",[170,213,215],{"class":214},"s5hCx"," HeavyWidget",[170,217,218],{"class":183}," =",[170,220,222],{"class":221},"sGhOu"," dynamic",[170,224,225],{"class":187},"(() ",[170,227,228],{"class":183},"=>",[170,230,231],{"class":183}," import",[170,233,234],{"class":187},"(",[170,236,237],{"class":194},"'..\u002Fcomponents\u002FHeavyWidget'",[170,239,240],{"class":187},"), {\n",[170,242,243,246,249,251,254,258,261,264,267,270,272],{"class":172,"line":133},[170,244,245],{"class":221}," loading",[170,247,248],{"class":187},": () ",[170,250,228],{"class":183},[170,252,253],{"class":187}," \u003C",[170,255,257],{"class":256},"sj_b3","div",[170,259,260],{"class":214}," className",[170,262,263],{"class":183},"=",[170,265,266],{"class":194},"\"skeleton\"",[170,268,269],{"class":187},">Loading module...\u003C\u002F",[170,271,257],{"class":256},[170,273,274],{"class":187},">,\n",[170,276,278,281,284,287],{"class":172,"line":277},6,[170,279,280],{"class":187}," ssr: ",[170,282,283],{"class":214},"false",[170,285,286],{"class":187},", ",[170,288,289],{"class":176},"\u002F\u002F Reserve strictly for browser-only APIs\n",[170,291,293],{"class":172,"line":292},7,[170,294,295],{"class":187},"});\n",[170,297,299],{"class":172,"line":298},8,[170,300,205],{"emptyLinePlaceholder":204},[170,302,304,307,310,313,316,320],{"class":172,"line":303},9,[170,305,306],{"class":183},"export",[170,308,309],{"class":183}," default",[170,311,312],{"class":183}," function",[170,314,315],{"class":221}," Dashboard",[170,317,319],{"class":318},"spFnL","() ",[170,321,322],{"class":187},"{\n",[170,324,326,329,331,334],{"class":172,"line":325},10,[170,327,328],{"class":183}," return",[170,330,253],{"class":187},[170,332,333],{"class":256},"HeavyWidget",[170,335,336],{"class":187}," \u002F>;\n",[170,338,340],{"class":172,"line":339},11,[170,341,342],{"class":187},"}\n",[146,344,346],{"id":345},"app-router-configuration","App Router Configuration",[14,348,349,350,352],{},"Leverage React Suspense boundaries alongside ",[47,351,63],{},". The App Router automatically chunks route segments, but explicit dynamic imports isolate heavy sub-components.",[161,354,356],{"className":163,"code":355,"language":165,"meta":166,"style":166},"\u002F\u002F app\u002Fdashboard\u002Fpage.tsx\nimport dynamic from 'next\u002Fdynamic';\nimport { Suspense } from 'react';\n\nconst AnalyticsPanel = dynamic(() => import('.\u002Fcomponents\u002FAnalyticsPanel'), {\n loading: () => \u003Cdiv className=\"skeleton\">Initializing chart engine...\u003C\u002Fdiv>,\n});\n\nexport default function DashboardRoute() {\n return (\n \u003CSuspense fallback={\u003Cdiv className=\"skeleton\">Loading route...\u003C\u002Fdiv>}>\n \u003CAnalyticsPanel \u002F>\n \u003C\u002FSuspense>\n );\n}\n",[47,357,358,363,375,389,393,417,442,446,450,465,472,510,521,531,537],{"__ignoreMap":166},[170,359,360],{"class":172,"line":173},[170,361,362],{"class":176},"\u002F\u002F app\u002Fdashboard\u002Fpage.tsx\n",[170,364,365,367,369,371,373],{"class":172,"line":180},[170,366,184],{"class":183},[170,368,188],{"class":187},[170,370,191],{"class":183},[170,372,195],{"class":194},[170,374,198],{"class":187},[170,376,377,379,382,384,387],{"class":172,"line":201},[170,378,184],{"class":183},[170,380,381],{"class":187}," { Suspense } ",[170,383,191],{"class":183},[170,385,386],{"class":194}," 'react'",[170,388,198],{"class":187},[170,390,391],{"class":172,"line":208},[170,392,205],{"emptyLinePlaceholder":204},[170,394,395,397,400,402,404,406,408,410,412,415],{"class":172,"line":133},[170,396,211],{"class":183},[170,398,399],{"class":214}," AnalyticsPanel",[170,401,218],{"class":183},[170,403,222],{"class":221},[170,405,225],{"class":187},[170,407,228],{"class":183},[170,409,231],{"class":183},[170,411,234],{"class":187},[170,413,414],{"class":194},"'.\u002Fcomponents\u002FAnalyticsPanel'",[170,416,240],{"class":187},[170,418,419,421,423,425,427,429,431,433,435,438,440],{"class":172,"line":277},[170,420,245],{"class":221},[170,422,248],{"class":187},[170,424,228],{"class":183},[170,426,253],{"class":187},[170,428,257],{"class":256},[170,430,260],{"class":214},[170,432,263],{"class":183},[170,434,266],{"class":194},[170,436,437],{"class":187},">Initializing chart engine...\u003C\u002F",[170,439,257],{"class":256},[170,441,274],{"class":187},[170,443,444],{"class":172,"line":292},[170,445,295],{"class":187},[170,447,448],{"class":172,"line":298},[170,449,205],{"emptyLinePlaceholder":204},[170,451,452,454,456,458,461,463],{"class":172,"line":303},[170,453,306],{"class":183},[170,455,309],{"class":183},[170,457,312],{"class":183},[170,459,460],{"class":221}," DashboardRoute",[170,462,319],{"class":318},[170,464,322],{"class":187},[170,466,467,469],{"class":172,"line":325},[170,468,328],{"class":183},[170,470,471],{"class":187}," (\n",[170,473,474,476,479,482,485,488,490,492,494,496,499,501,504,507],{"class":172,"line":339},[170,475,253],{"class":187},[170,477,478],{"class":256},"Suspense",[170,480,481],{"class":214}," fallback",[170,483,484],{"class":183},"={",[170,486,487],{"class":187},"\u003C",[170,489,257],{"class":256},[170,491,260],{"class":214},[170,493,263],{"class":183},[170,495,266],{"class":194},[170,497,498],{"class":187},">Loading route...\u003C\u002F",[170,500,257],{"class":256},[170,502,503],{"class":187},">",[170,505,506],{"class":183},"}",[170,508,509],{"class":187},">\n",[170,511,513,515,518],{"class":172,"line":512},12,[170,514,253],{"class":187},[170,516,517],{"class":256},"AnalyticsPanel",[170,519,520],{"class":187}," \u002F>\n",[170,522,524,527,529],{"class":172,"line":523},13,[170,525,526],{"class":187}," \u003C\u002F",[170,528,478],{"class":256},[170,530,509],{"class":187},[170,532,534],{"class":172,"line":533},14,[170,535,536],{"class":187}," );\n",[170,538,540],{"class":172,"line":539},15,[170,541,342],{"class":187},[146,543,545,546,548],{"id":544},"webpack-splitchunks-override","Webpack ",[47,547,54],{}," Override",[14,550,551,552,554],{},"Enforce route isolation without fragmenting shared dependencies. 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reuseExistingChunk: ",[170,982,753],{"class":214},[170,984,636],{"class":187},[170,986,988],{"class":172,"line":987},27,[170,989,760],{"class":187},[170,991,993],{"class":172,"line":992},28,[170,994,995],{"class":187}," commons: {\n",[170,997,999,1001,1004],{"class":172,"line":998},29,[170,1000,665],{"class":187},[170,1002,1003],{"class":194},"'commons'",[170,1005,636],{"class":187},[170,1007,1009,1011,1014],{"class":172,"line":1008},30,[170,1010,969],{"class":187},[170,1012,1013],{"class":214},"2",[170,1015,636],{"class":187},[170,1017,1019,1021,1024],{"class":172,"line":1018},31,[170,1020,740],{"class":187},[170,1022,1023],{"class":214},"20",[170,1025,636],{"class":187},[170,1027,1029],{"class":172,"line":1028},32,[170,1030,760],{"class":187},[170,1032,1034],{"class":172,"line":1033},33,[170,1035,760],{"class":187},[170,1037,1039],{"class":172,"line":1038},34,[170,1040,1041],{"class":187}," };\n",[170,1043,1045],{"class":172,"line":1044},35,[170,1046,1047],{"class":187}," 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Verify chunk distribution visually.",[35,1088,1089,1090,1093],{},"Add a CI gate: Parse ",[47,1091,1092],{},".next\u002Fbuild-manifest.json",". Fail the pipeline if any route-specific JS file exceeds 150KB.",[35,1095,1096,1097,1100,1101,892],{},"Inspect ",[47,1098,1099],{},"next build"," terminal output. Confirm route chunks are named predictably (e.g., ",[47,1102,1103],{},"dashboard-[hash].js",[35,1105,1106,1107,1110],{},"Verify route transitions in DevTools Network. Only delta chunks should fetch. No full ",[47,1108,1109],{},"framework.js"," reloads.",[35,1112,1113,1114,1117],{},"Monitor hydration mismatches. Aggressive client-side splitting often triggers console warnings. Use ",[47,1115,1116],{},"use client"," boundaries carefully to prevent SSR\u002Fclient divergence.",[24,1119,1121],{"id":1120},"advanced-tuning-prefetching-cache-strategies","Advanced Tuning: Prefetching & Cache Strategies",[14,1123,1124],{},"Optimize route transitions and network delivery with these targeted adjustments:",[32,1126,1127,1138,1145,1148],{},[35,1128,1129,1130,1133,1134,1137],{},"Next.js automatically prefetches linked routes on hover. Control this via ",[47,1131,1132],{},"\u003CLink prefetch={true}>"," for high-priority paths and ",[47,1135,1136],{},"prefetch={false}"," for low-traffic routes.",[35,1139,1140,1141,1144],{},"Configure CDN\u002Forigin headers for split chunks: ",[47,1142,1143],{},"Cache-Control: public, max-age=31536000, immutable",". Content hashes guarantee safe long-term caching.",[35,1146,1147],{},"When chunk hashes change, browsers fetch only the modified assets. Ensure your deployment pipeline clears stale CDN paths if you use custom cache keys.",[35,1149,1150,1151,1154],{},"Balance split granularity with HTTP\u002F2 multiplexing. Avoid generating >30 concurrent requests per route. Set ",[47,1152,1153],{},"maxInitialRequests: 30"," in webpack config to prevent request waterfalls on constrained networks.",[146,1156,1158],{"id":1157},"common-mistakes-fixes","Common Mistakes & Fixes",[32,1160,1161,1178,1199],{},[35,1162,1163,1166,1167,1170,1171,1174,1175,892],{},[38,1164,1165],{},"Mistake:"," Barrel\u002Findex imports across routes. ",[38,1168,1169],{},"Impact:"," Monolithic bundles blocking FCP. ",[38,1172,1173],{},"Fix:"," Use direct file paths (",[47,1176,1177],{},"import A from '.\u002FA'",[35,1179,1180,1182,1183,1186,1187,1189,1190,1192,1193,1196,1197,55],{},[38,1181,1165],{}," Aggressive ",[47,1184,1185],{},"minChunks: 1",". ",[38,1188,1169],{}," Dozens of \u003C10KB chunks, HTTP waterfall, high TTI. ",[38,1191,1173],{}," Set ",[47,1194,1195],{},"minChunks: 2"," for shared utilities, cap ",[47,1198,1153],{},[35,1200,1201,1203,1204,1206,1207,1209,1210,1212,1213,1215,1216,733,1219,1222],{},[38,1202,1165],{}," ",[47,1205,158],{}," on above-the-fold UI. ",[38,1208,1169],{}," Delayed LCP, hydration mismatches. ",[38,1211,1173],{}," Reserve ",[47,1214,158],{}," for ",[47,1217,1218],{},"window",[47,1220,1221],{},"navigator"," APIs only.",[24,1224,1226],{"id":1225},"faq","FAQ",[14,1228,1229,1232],{},[38,1230,1231],{},"Does Next.js automatically split code by route in the App Router?","\nYes. Next.js App Router automatically creates a separate JavaScript chunk for each route segment. However, improper imports (like barrel files) or shared state providers can merge these chunks back together, negating the automatic splitting.",[14,1234,1235,1238],{},[38,1236,1237],{},"What is the maximum recommended size for a single route chunk?","\nFor optimal FCP and TTI on 4G\u002F3G networks, keep the initial route chunk under 150KB (minified + gzipped). Use Lighthouse and Webpack Bundle Analyzer to enforce this threshold during CI.",[14,1240,1241,1244,1245,1248,1249,1251,1252,1254],{},[38,1242,1243],{},"How do I prevent vendor libraries from duplicating across route chunks?","\nConfigure ",[47,1246,1247],{},"splitChunks.cacheGroups.framework"," in ",[47,1250,49],{}," to extract React, Next.js, and core dependencies into a single cached ",[47,1253,1109],{}," chunk that is shared across all routes.",[14,1256,1257,1267,1268,1270,1271,1273],{},[38,1258,1259,1260,1262,1263,1266],{},"When should I use ",[47,1261,63],{}," versus ",[47,1264,1265],{},"React.lazy","?","\nAlways prefer ",[47,1269,63],{}," in Next.js. It integrates with Next.js SSR, handles loading states, supports ",[47,1272,158],{},", and automatically manages webpack chunk boundaries without manual Suspense configuration.",[1275,1276,1277],"style",{},"html pre.shiki code .sXJMR, html code.shiki .sXJMR{--shiki-default:#BDC4CC;--shiki-dark:#BDC4CC;--shiki-light:#66707B}html pre.shiki code .sCJTb, html code.shiki .sCJTb{--shiki-default:#FF9492;--shiki-dark:#FF9492;--shiki-light:#A0111F}html pre.shiki code .s3sCt, html code.shiki .s3sCt{--shiki-default:#F0F3F6;--shiki-dark:#F0F3F6;--shiki-light:#0E1116}html pre.shiki code .sJdzJ, html code.shiki .sJdzJ{--shiki-default:#ADDCFF;--shiki-dark:#ADDCFF;--shiki-light:#032563}html pre.shiki code .s5hCx, html code.shiki .s5hCx{--shiki-default:#91CBFF;--shiki-dark:#91CBFF;--shiki-light:#023B95}html pre.shiki code .sGhOu, html code.shiki .sGhOu{--shiki-default:#DBB7FF;--shiki-dark:#DBB7FF;--shiki-light:#622CBC}html pre.shiki code .sj_b3, html code.shiki .sj_b3{--shiki-default:#72F088;--shiki-dark:#72F088;--shiki-light:#024C1A}html pre.shiki code .spFnL, html code.shiki .spFnL{--shiki-default:#FFB757;--shiki-dark:#FFB757;--shiki-light:#702C00}html .default .shiki span {color: var(--shiki-default);background: var(--shiki-default-bg);font-style: var(--shiki-default-font-style);font-weight: var(--shiki-default-font-weight);text-decoration: var(--shiki-default-text-decoration);}html .shiki span {color: var(--shiki-default);background: var(--shiki-default-bg);font-style: var(--shiki-default-font-style);font-weight: var(--shiki-default-font-weight);text-decoration: var(--shiki-default-text-decoration);}html .dark .shiki span {color: var(--shiki-dark);background: var(--shiki-dark-bg);font-style: var(--shiki-dark-font-style);font-weight: var(--shiki-dark-font-weight);text-decoration: var(--shiki-dark-text-decoration);}html.dark .shiki span {color: var(--shiki-dark);background: var(--shiki-dark-bg);font-style: var(--shiki-dark-font-style);font-weight: var(--shiki-dark-font-weight);text-decoration: var(--shiki-dark-text-decoration);}html .light .shiki span {color: var(--shiki-light);background: var(--shiki-light-bg);font-style: var(--shiki-light-font-style);font-weight: var(--shiki-light-font-weight);text-decoration: var(--shiki-light-text-decoration);}html.light .shiki span {color: var(--shiki-light);background: var(--shiki-light-bg);font-style: var(--shiki-light-font-style);font-weight: var(--shiki-light-font-weight);text-decoration: var(--shiki-light-text-decoration);}html pre.shiki code .s1o6E, html code.shiki .s1o6E{--shiki-default:#72F088;--shiki-default-font-weight:bold;--shiki-dark:#72F088;--shiki-dark-font-weight:bold;--shiki-light:#024C1A;--shiki-light-font-weight:bold}",{"title":166,"searchDepth":180,"depth":180,"links":1279},[1280,1281,1282,1288,1289,1292],{"id":26,"depth":180,"text":27},{"id":80,"depth":180,"text":81},{"id":143,"depth":180,"text":144,"children":1283},[1284,1285,1286],{"id":148,"depth":201,"text":149},{"id":345,"depth":201,"text":346},{"id":544,"depth":201,"text":1287},"Webpack splitChunks Override",{"id":1069,"depth":180,"text":1070},{"id":1120,"depth":180,"text":1121,"children":1290},[1291],{"id":1157,"depth":201,"text":1158},{"id":1225,"depth":180,"text":1226},"Route-level code splitting is foundational to JavaScript Bundle Optimization & Code Splitting, yet many Next.js deployments suffer from degraded FCP and TTI due to misconfigured chunk boundaries. This guide targets a specific regression: monolithic route bundles caused by improper barrel exports, missing dynamic boundaries, or overridden webpack defaults. We will diagnose exact failure points using DevTools Network and Lighthouse, apply precise configuration fixes, and validate against strict performance thresholds.","md",{},"\u002Fjavascript-bundle-optimization-code-splitting\u002Fdynamic-imports-and-route-based-splitting\u002Fimplementing-route-level-code-splitting-in-nextjs",{"title":5,"description":1293},"javascript-bundle-optimization-code-splitting\u002Fdynamic-imports-and-route-based-splitting\u002Fimplementing-route-level-code-splitting-in-nextjs\u002Findex","DTJvzAIja4HN6VzZ-Wb8AYSSilY1LiCSm9VxwgHGiYA",[1301,1305],{"title":1302,"path":1303,"stem":1304,"children":-1},"Dynamic Imports and Route-Based Splitting: Implementation Guide & Performance Thresholds","\u002Fjavascript-bundle-optimization-code-splitting\u002Fdynamic-imports-and-route-based-splitting","javascript-bundle-optimization-code-splitting\u002Fdynamic-imports-and-route-based-splitting\u002Findex",{"title":1306,"path":1307,"stem":1308,"children":-1},"Modern Module Formats: ESM vs CommonJS","\u002Fjavascript-bundle-optimization-code-splitting\u002Fmodern-module-formats-esm-vs-commonjs","javascript-bundle-optimization-code-splitting\u002Fmodern-module-formats-esm-vs-commonjs\u002Findex",1777925998808]