Episode 2 — React Frontend Architecture NextJS / 2.18 — Getting Started with NextJS
2.18.e — Layouts in Next.js
In one sentence: Layouts are nested server component shells that share chrome across routes, with explicit differences from templates for remount behavior and advanced parallel slot patterns.
Navigation: ← File-Based Routing · → 2.18 Overview
1. Layouts compose like nested UI shells
layout.tsx wraps child segments and persists across navigations within its subtree (state in layout components can survive soft navigations—be intentional).
1.1 Root layout rules
Must include <html> and <body> once. Global styles and fonts often live here.
1.2 Layout vs template.tsx
Layout: stable shell, does not remount on navigation between siblings.
Template: remounts on navigation—useful for enter/exit animations or keyed resets.
1.3 Parallel and intercepting routes (awareness)
Advanced patterns for dashboards/modals—know they exist; deep dive when requirements appear.
1.4 Metadata
export const metadata / generateMetadata — SEO defaults often centralized in root or segment layouts.
Part 2 — Deep Encyclopedia (Layouts in Next.js)
How to use: Each drill = scenario → interview prompt → model answer → optional code sketch. Answers emphasize trade-offs and what you would verify in a real repo.
E001 — Drill 1: Root layout must include <html> and <body>.
Scenario: Root layout must include <html> and <body>. (variation 1: assume App Router, TypeScript, and a product team shipping weekly.)
Prompt: What decision do you make, what do you document, and what metric or artifact proves the outcome for case #1?
Model answer: I restate constraints (team size, SEO needs, deploy target, latency budget). I pick the smallest reversible step—often a spike branch or preview deployment—and define one success signal (e.g. p75 LCP, build time, DX survey). For drill #1, I call out risks (lock-in, complexity, training) and mitigations (abstraction layers, coding standards, ADRs). I avoid absolutes: Next fits when routing + rendering + deployment integration reduce total cost versus bolting libraries onto React alone.
// app/dashboard/layout.tsx
export default function DashboardLayout({ children }: { children: React.ReactNode }) {
return (
<div className="flex">
<aside>Nav</aside>
<section>{children}</section>
</div>
);
}
E002 — Drill 2: Nested layout adds sidebar only for /dashboard subtree.
Scenario: Nested layout adds sidebar only for /dashboard subtree. (variation 2: assume App Router, TypeScript, and a product team shipping weekly.)
Prompt: What decision do you make, what do you document, and what metric or artifact proves the outcome for case #2?
Model answer: I restate constraints (team size, SEO needs, deploy target, latency budget). I pick the smallest reversible step—often a spike branch or preview deployment—and define one success signal (e.g. p75 LCP, build time, DX survey). For drill #2, I call out risks (lock-in, complexity, training) and mitigations (abstraction layers, coding standards, ADRs). I avoid absolutes: Next fits when routing + rendering + deployment integration reduce total cost versus bolting libraries onto React alone.
// app/dashboard/layout.tsx
export default function DashboardLayout({ children }: { children: React.ReactNode }) {
return (
<div className="flex">
<aside>Nav</aside>
<section>{children}</section>
</div>
);
}
E003 — Drill 3: Layout vs template re-mount behavior difference.
Scenario: Layout vs template re-mount behavior difference. (variation 3: assume App Router, TypeScript, and a product team shipping weekly.)
Prompt: What decision do you make, what do you document, and what metric or artifact proves the outcome for case #3?
Model answer: I restate constraints (team size, SEO needs, deploy target, latency budget). I pick the smallest reversible step—often a spike branch or preview deployment—and define one success signal (e.g. p75 LCP, build time, DX survey). For drill #3, I call out risks (lock-in, complexity, training) and mitigations (abstraction layers, coding standards, ADRs). I avoid absolutes: Next fits when routing + rendering + deployment integration reduce total cost versus bolting libraries onto React alone.
// app/dashboard/layout.tsx
export default function DashboardLayout({ children }: { children: React.ReactNode }) {
return (
<div className="flex">
<aside>Nav</aside>
<section>{children}</section>
</div>
);
}
E004 — Drill 4: Loading.tsx skeleton hierarchy per segment.
Scenario: Loading.tsx skeleton hierarchy per segment. (variation 4: assume App Router, TypeScript, and a product team shipping weekly.)
Prompt: What decision do you make, what do you document, and what metric or artifact proves the outcome for case #4?
Model answer: I restate constraints (team size, SEO needs, deploy target, latency budget). I pick the smallest reversible step—often a spike branch or preview deployment—and define one success signal (e.g. p75 LCP, build time, DX survey). For drill #4, I call out risks (lock-in, complexity, training) and mitigations (abstraction layers, coding standards, ADRs). I avoid absolutes: Next fits when routing + rendering + deployment integration reduce total cost versus bolting libraries onto React alone.
// app/dashboard/layout.tsx
export default function DashboardLayout({ children }: { children: React.ReactNode }) {
return (
<div className="flex">
<aside>Nav</aside>
<section>{children}</section>
</div>
);
}
E005 — Drill 5: Error.tsx boundary scope for segment failures.
Scenario: Error.tsx boundary scope for segment failures. (variation 5: assume App Router, TypeScript, and a product team shipping weekly.)
Prompt: What decision do you make, what do you document, and what metric or artifact proves the outcome for case #5?
Model answer: I restate constraints (team size, SEO needs, deploy target, latency budget). I pick the smallest reversible step—often a spike branch or preview deployment—and define one success signal (e.g. p75 LCP, build time, DX survey). For drill #5, I call out risks (lock-in, complexity, training) and mitigations (abstraction layers, coding standards, ADRs). I avoid absolutes: Next fits when routing + rendering + deployment integration reduce total cost versus bolting libraries onto React alone.
// app/dashboard/layout.tsx
export default function DashboardLayout({ children }: { children: React.ReactNode }) {
return (
<div className="flex">
<aside>Nav</aside>
<section>{children}</section>
</div>
);
}
E006 — Drill 6: Multiple children slots in parallel routes layout.
Scenario: Multiple children slots in parallel routes layout. (variation 6: assume App Router, TypeScript, and a product team shipping weekly.)
Prompt: What decision do you make, what do you document, and what metric or artifact proves the outcome for case #6?
Model answer: I restate constraints (team size, SEO needs, deploy target, latency budget). I pick the smallest reversible step—often a spike branch or preview deployment—and define one success signal (e.g. p75 LCP, build time, DX survey). For drill #6, I call out risks (lock-in, complexity, training) and mitigations (abstraction layers, coding standards, ADRs). I avoid absolutes: Next fits when routing + rendering + deployment integration reduce total cost versus bolting libraries onto React alone.
// app/dashboard/layout.tsx
export default function DashboardLayout({ children }: { children: React.ReactNode }) {
return (
<div className="flex">
<aside>Nav</aside>
<section>{children}</section>
</div>
);
}
E007 — Drill 7: Font optimization via next/font in root layout.
Scenario: Font optimization via next/font in root layout. (variation 7: assume App Router, TypeScript, and a product team shipping weekly.)
Prompt: What decision do you make, what do you document, and what metric or artifact proves the outcome for case #7?
Model answer: I restate constraints (team size, SEO needs, deploy target, latency budget). I pick the smallest reversible step—often a spike branch or preview deployment—and define one success signal (e.g. p75 LCP, build time, DX survey). For drill #7, I call out risks (lock-in, complexity, training) and mitigations (abstraction layers, coding standards, ADRs). I avoid absolutes: Next fits when routing + rendering + deployment integration reduce total cost versus bolting libraries onto React alone.
// app/dashboard/layout.tsx
export default function DashboardLayout({ children }: { children: React.ReactNode }) {
return (
<div className="flex">
<aside>Nav</aside>
<section>{children}</section>
</div>
);
}
E008 — Drill 8: Metadata API in layout vs page precedence.
Scenario: Metadata API in layout vs page precedence. (variation 8: assume App Router, TypeScript, and a product team shipping weekly.)
Prompt: What decision do you make, what do you document, and what metric or artifact proves the outcome for case #8?
Model answer: I restate constraints (team size, SEO needs, deploy target, latency budget). I pick the smallest reversible step—often a spike branch or preview deployment—and define one success signal (e.g. p75 LCP, build time, DX survey). For drill #8, I call out risks (lock-in, complexity, training) and mitigations (abstraction layers, coding standards, ADRs). I avoid absolutes: Next fits when routing + rendering + deployment integration reduce total cost versus bolting libraries onto React alone.
// app/dashboard/layout.tsx
export default function DashboardLayout({ children }: { children: React.ReactNode }) {
return (
<div className="flex">
<aside>Nav</aside>
<section>{children}</section>
</div>
);
}
E009 — Drill 9: Avoiding duplicate headers across nested layouts.
Scenario: Avoiding duplicate headers across nested layouts. (variation 9: assume App Router, TypeScript, and a product team shipping weekly.)
Prompt: What decision do you make, what do you document, and what metric or artifact proves the outcome for case #9?
Model answer: I restate constraints (team size, SEO needs, deploy target, latency budget). I pick the smallest reversible step—often a spike branch or preview deployment—and define one success signal (e.g. p75 LCP, build time, DX survey). For drill #9, I call out risks (lock-in, complexity, training) and mitigations (abstraction layers, coding standards, ADRs). I avoid absolutes: Next fits when routing + rendering + deployment integration reduce total cost versus bolting libraries onto React alone.
// app/dashboard/layout.tsx
export default function DashboardLayout({ children }: { children: React.ReactNode }) {
return (
<div className="flex">
<aside>Nav</aside>
<section>{children}</section>
</div>
);
}
E010 — Drill 10: Migrating Pages Router _app global layout to App Router.
Scenario: Migrating Pages Router _app global layout to App Router. (variation 10: assume App Router, TypeScript, and a product team shipping weekly.)
Prompt: What decision do you make, what do you document, and what metric or artifact proves the outcome for case #10?
Model answer: I restate constraints (team size, SEO needs, deploy target, latency budget). I pick the smallest reversible step—often a spike branch or preview deployment—and define one success signal (e.g. p75 LCP, build time, DX survey). For drill #10, I call out risks (lock-in, complexity, training) and mitigations (abstraction layers, coding standards, ADRs). I avoid absolutes: Next fits when routing + rendering + deployment integration reduce total cost versus bolting libraries onto React alone.
// app/dashboard/layout.tsx
export default function DashboardLayout({ children }: { children: React.ReactNode }) {
return (
<div className="flex">
<aside>Nav</aside>
<section>{children}</section>
</div>
);
}
E011 — Drill 11: Root layout must include <html> and <body>.
Scenario: Root layout must include <html> and <body>. (variation 11: assume App Router, TypeScript, and a product team shipping weekly.)
Prompt: What decision do you make, what do you document, and what metric or artifact proves the outcome for case #11?
Model answer: I restate constraints (team size, SEO needs, deploy target, latency budget). I pick the smallest reversible step—often a spike branch or preview deployment—and define one success signal (e.g. p75 LCP, build time, DX survey). For drill #11, I call out risks (lock-in, complexity, training) and mitigations (abstraction layers, coding standards, ADRs). I avoid absolutes: Next fits when routing + rendering + deployment integration reduce total cost versus bolting libraries onto React alone.
// app/dashboard/layout.tsx
export default function DashboardLayout({ children }: { children: React.ReactNode }) {
return (
<div className="flex">
<aside>Nav</aside>
<section>{children}</section>
</div>
);
}
E012 — Drill 12: Nested layout adds sidebar only for /dashboard subtree.
Scenario: Nested layout adds sidebar only for /dashboard subtree. (variation 12: assume App Router, TypeScript, and a product team shipping weekly.)
Prompt: What decision do you make, what do you document, and what metric or artifact proves the outcome for case #12?
Model answer: I restate constraints (team size, SEO needs, deploy target, latency budget). I pick the smallest reversible step—often a spike branch or preview deployment—and define one success signal (e.g. p75 LCP, build time, DX survey). For drill #12, I call out risks (lock-in, complexity, training) and mitigations (abstraction layers, coding standards, ADRs). I avoid absolutes: Next fits when routing + rendering + deployment integration reduce total cost versus bolting libraries onto React alone.
// app/dashboard/layout.tsx
export default function DashboardLayout({ children }: { children: React.ReactNode }) {
return (
<div className="flex">
<aside>Nav</aside>
<section>{children}</section>
</div>
);
}
E013 — Drill 13: Layout vs template re-mount behavior difference.
Scenario: Layout vs template re-mount behavior difference. (variation 13: assume App Router, TypeScript, and a product team shipping weekly.)
Prompt: What decision do you make, what do you document, and what metric or artifact proves the outcome for case #13?
Model answer: I restate constraints (team size, SEO needs, deploy target, latency budget). I pick the smallest reversible step—often a spike branch or preview deployment—and define one success signal (e.g. p75 LCP, build time, DX survey). For drill #13, I call out risks (lock-in, complexity, training) and mitigations (abstraction layers, coding standards, ADRs). I avoid absolutes: Next fits when routing + rendering + deployment integration reduce total cost versus bolting libraries onto React alone.
// app/dashboard/layout.tsx
export default function DashboardLayout({ children }: { children: React.ReactNode }) {
return (
<div className="flex">
<aside>Nav</aside>
<section>{children}</section>
</div>
);
}
E014 — Drill 14: Loading.tsx skeleton hierarchy per segment.
Scenario: Loading.tsx skeleton hierarchy per segment. (variation 14: assume App Router, TypeScript, and a product team shipping weekly.)
Prompt: What decision do you make, what do you document, and what metric or artifact proves the outcome for case #14?
Model answer: I restate constraints (team size, SEO needs, deploy target, latency budget). I pick the smallest reversible step—often a spike branch or preview deployment—and define one success signal (e.g. p75 LCP, build time, DX survey). For drill #14, I call out risks (lock-in, complexity, training) and mitigations (abstraction layers, coding standards, ADRs). I avoid absolutes: Next fits when routing + rendering + deployment integration reduce total cost versus bolting libraries onto React alone.
// app/dashboard/layout.tsx
export default function DashboardLayout({ children }: { children: React.ReactNode }) {
return (
<div className="flex">
<aside>Nav</aside>
<section>{children}</section>
</div>
);
}
E015 — Drill 15: Error.tsx boundary scope for segment failures.
Scenario: Error.tsx boundary scope for segment failures. (variation 15: assume App Router, TypeScript, and a product team shipping weekly.)
Prompt: What decision do you make, what do you document, and what metric or artifact proves the outcome for case #15?
Model answer: I restate constraints (team size, SEO needs, deploy target, latency budget). I pick the smallest reversible step—often a spike branch or preview deployment—and define one success signal (e.g. p75 LCP, build time, DX survey). For drill #15, I call out risks (lock-in, complexity, training) and mitigations (abstraction layers, coding standards, ADRs). I avoid absolutes: Next fits when routing + rendering + deployment integration reduce total cost versus bolting libraries onto React alone.
// app/dashboard/layout.tsx
export default function DashboardLayout({ children }: { children: React.ReactNode }) {
return (
<div className="flex">
<aside>Nav</aside>
<section>{children}</section>
</div>
);
}
E016 — Drill 16: Multiple children slots in parallel routes layout.
Scenario: Multiple children slots in parallel routes layout. (variation 16: assume App Router, TypeScript, and a product team shipping weekly.)
Prompt: What decision do you make, what do you document, and what metric or artifact proves the outcome for case #16?
Model answer: I restate constraints (team size, SEO needs, deploy target, latency budget). I pick the smallest reversible step—often a spike branch or preview deployment—and define one success signal (e.g. p75 LCP, build time, DX survey). For drill #16, I call out risks (lock-in, complexity, training) and mitigations (abstraction layers, coding standards, ADRs). I avoid absolutes: Next fits when routing + rendering + deployment integration reduce total cost versus bolting libraries onto React alone.
// app/dashboard/layout.tsx
export default function DashboardLayout({ children }: { children: React.ReactNode }) {
return (
<div className="flex">
<aside>Nav</aside>
<section>{children}</section>
</div>
);
}
E017 — Drill 17: Font optimization via next/font in root layout.
Scenario: Font optimization via next/font in root layout. (variation 17: assume App Router, TypeScript, and a product team shipping weekly.)
Prompt: What decision do you make, what do you document, and what metric or artifact proves the outcome for case #17?
Model answer: I restate constraints (team size, SEO needs, deploy target, latency budget). I pick the smallest reversible step—often a spike branch or preview deployment—and define one success signal (e.g. p75 LCP, build time, DX survey). For drill #17, I call out risks (lock-in, complexity, training) and mitigations (abstraction layers, coding standards, ADRs). I avoid absolutes: Next fits when routing + rendering + deployment integration reduce total cost versus bolting libraries onto React alone.
// app/dashboard/layout.tsx
export default function DashboardLayout({ children }: { children: React.ReactNode }) {
return (
<div className="flex">
<aside>Nav</aside>
<section>{children}</section>
</div>
);
}
E018 — Drill 18: Metadata API in layout vs page precedence.
Scenario: Metadata API in layout vs page precedence. (variation 18: assume App Router, TypeScript, and a product team shipping weekly.)
Prompt: What decision do you make, what do you document, and what metric or artifact proves the outcome for case #18?
Model answer: I restate constraints (team size, SEO needs, deploy target, latency budget). I pick the smallest reversible step—often a spike branch or preview deployment—and define one success signal (e.g. p75 LCP, build time, DX survey). For drill #18, I call out risks (lock-in, complexity, training) and mitigations (abstraction layers, coding standards, ADRs). I avoid absolutes: Next fits when routing + rendering + deployment integration reduce total cost versus bolting libraries onto React alone.
// app/dashboard/layout.tsx
export default function DashboardLayout({ children }: { children: React.ReactNode }) {
return (
<div className="flex">
<aside>Nav</aside>
<section>{children}</section>
</div>
);
}
E019 — Drill 19: Avoiding duplicate headers across nested layouts.
Scenario: Avoiding duplicate headers across nested layouts. (variation 19: assume App Router, TypeScript, and a product team shipping weekly.)
Prompt: What decision do you make, what do you document, and what metric or artifact proves the outcome for case #19?
Model answer: I restate constraints (team size, SEO needs, deploy target, latency budget). I pick the smallest reversible step—often a spike branch or preview deployment—and define one success signal (e.g. p75 LCP, build time, DX survey). For drill #19, I call out risks (lock-in, complexity, training) and mitigations (abstraction layers, coding standards, ADRs). I avoid absolutes: Next fits when routing + rendering + deployment integration reduce total cost versus bolting libraries onto React alone.
// app/dashboard/layout.tsx
export default function DashboardLayout({ children }: { children: React.ReactNode }) {
return (
<div className="flex">
<aside>Nav</aside>
<section>{children}</section>
</div>
);
}
E020 — Drill 20: Migrating Pages Router _app global layout to App Router.
Scenario: Migrating Pages Router _app global layout to App Router. (variation 20: assume App Router, TypeScript, and a product team shipping weekly.)
Prompt: What decision do you make, what do you document, and what metric or artifact proves the outcome for case #20?
Model answer: I restate constraints (team size, SEO needs, deploy target, latency budget). I pick the smallest reversible step—often a spike branch or preview deployment—and define one success signal (e.g. p75 LCP, build time, DX survey). For drill #20, I call out risks (lock-in, complexity, training) and mitigations (abstraction layers, coding standards, ADRs). I avoid absolutes: Next fits when routing + rendering + deployment integration reduce total cost versus bolting libraries onto React alone.
// app/dashboard/layout.tsx
export default function DashboardLayout({ children }: { children: React.ReactNode }) {
return (
<div className="flex">
<aside>Nav</aside>
<section>{children}</section>
</div>
);
}
E021 — Drill 21: Root layout must include <html> and <body>.
Scenario: Root layout must include <html> and <body>. (variation 21: assume App Router, TypeScript, and a product team shipping weekly.)
Prompt: What decision do you make, what do you document, and what metric or artifact proves the outcome for case #21?
Model answer: I restate constraints (team size, SEO needs, deploy target, latency budget). I pick the smallest reversible step—often a spike branch or preview deployment—and define one success signal (e.g. p75 LCP, build time, DX survey). For drill #21, I call out risks (lock-in, complexity, training) and mitigations (abstraction layers, coding standards, ADRs). I avoid absolutes: Next fits when routing + rendering + deployment integration reduce total cost versus bolting libraries onto React alone.
// app/dashboard/layout.tsx
export default function DashboardLayout({ children }: { children: React.ReactNode }) {
return (
<div className="flex">
<aside>Nav</aside>
<section>{children}</section>
</div>
);
}
E022 — Drill 22: Nested layout adds sidebar only for /dashboard subtree.
Scenario: Nested layout adds sidebar only for /dashboard subtree. (variation 22: assume App Router, TypeScript, and a product team shipping weekly.)
Prompt: What decision do you make, what do you document, and what metric or artifact proves the outcome for case #22?
Model answer: I restate constraints (team size, SEO needs, deploy target, latency budget). I pick the smallest reversible step—often a spike branch or preview deployment—and define one success signal (e.g. p75 LCP, build time, DX survey). For drill #22, I call out risks (lock-in, complexity, training) and mitigations (abstraction layers, coding standards, ADRs). I avoid absolutes: Next fits when routing + rendering + deployment integration reduce total cost versus bolting libraries onto React alone.
// app/dashboard/layout.tsx
export default function DashboardLayout({ children }: { children: React.ReactNode }) {
return (
<div className="flex">
<aside>Nav</aside>
<section>{children}</section>
</div>
);
}
E023 — Drill 23: Layout vs template re-mount behavior difference.
Scenario: Layout vs template re-mount behavior difference. (variation 23: assume App Router, TypeScript, and a product team shipping weekly.)
Prompt: What decision do you make, what do you document, and what metric or artifact proves the outcome for case #23?
Model answer: I restate constraints (team size, SEO needs, deploy target, latency budget). I pick the smallest reversible step—often a spike branch or preview deployment—and define one success signal (e.g. p75 LCP, build time, DX survey). For drill #23, I call out risks (lock-in, complexity, training) and mitigations (abstraction layers, coding standards, ADRs). I avoid absolutes: Next fits when routing + rendering + deployment integration reduce total cost versus bolting libraries onto React alone.
// app/dashboard/layout.tsx
export default function DashboardLayout({ children }: { children: React.ReactNode }) {
return (
<div className="flex">
<aside>Nav</aside>
<section>{children}</section>
</div>
);
}
E024 — Drill 24: Loading.tsx skeleton hierarchy per segment.
Scenario: Loading.tsx skeleton hierarchy per segment. (variation 24: assume App Router, TypeScript, and a product team shipping weekly.)
Prompt: What decision do you make, what do you document, and what metric or artifact proves the outcome for case #24?
Model answer: I restate constraints (team size, SEO needs, deploy target, latency budget). I pick the smallest reversible step—often a spike branch or preview deployment—and define one success signal (e.g. p75 LCP, build time, DX survey). For drill #24, I call out risks (lock-in, complexity, training) and mitigations (abstraction layers, coding standards, ADRs). I avoid absolutes: Next fits when routing + rendering + deployment integration reduce total cost versus bolting libraries onto React alone.
// app/dashboard/layout.tsx
export default function DashboardLayout({ children }: { children: React.ReactNode }) {
return (
<div className="flex">
<aside>Nav</aside>
<section>{children}</section>
</div>
);
}
E025 — Drill 25: Error.tsx boundary scope for segment failures.
Scenario: Error.tsx boundary scope for segment failures. (variation 25: assume App Router, TypeScript, and a product team shipping weekly.)
Prompt: What decision do you make, what do you document, and what metric or artifact proves the outcome for case #25?
Model answer: I restate constraints (team size, SEO needs, deploy target, latency budget). I pick the smallest reversible step—often a spike branch or preview deployment—and define one success signal (e.g. p75 LCP, build time, DX survey). For drill #25, I call out risks (lock-in, complexity, training) and mitigations (abstraction layers, coding standards, ADRs). I avoid absolutes: Next fits when routing + rendering + deployment integration reduce total cost versus bolting libraries onto React alone.
// app/dashboard/layout.tsx
export default function DashboardLayout({ children }: { children: React.ReactNode }) {
return (
<div className="flex">
<aside>Nav</aside>
<section>{children}</section>
</div>
);
}
E026 — Drill 26: Multiple children slots in parallel routes layout.
Scenario: Multiple children slots in parallel routes layout. (variation 26: assume App Router, TypeScript, and a product team shipping weekly.)
Prompt: What decision do you make, what do you document, and what metric or artifact proves the outcome for case #26?
Model answer: I restate constraints (team size, SEO needs, deploy target, latency budget). I pick the smallest reversible step—often a spike branch or preview deployment—and define one success signal (e.g. p75 LCP, build time, DX survey). For drill #26, I call out risks (lock-in, complexity, training) and mitigations (abstraction layers, coding standards, ADRs). I avoid absolutes: Next fits when routing + rendering + deployment integration reduce total cost versus bolting libraries onto React alone.
// app/dashboard/layout.tsx
export default function DashboardLayout({ children }: { children: React.ReactNode }) {
return (
<div className="flex">
<aside>Nav</aside>
<section>{children}</section>
</div>
);
}
E027 — Drill 27: Font optimization via next/font in root layout.
Scenario: Font optimization via next/font in root layout. (variation 27: assume App Router, TypeScript, and a product team shipping weekly.)
Prompt: What decision do you make, what do you document, and what metric or artifact proves the outcome for case #27?
Model answer: I restate constraints (team size, SEO needs, deploy target, latency budget). I pick the smallest reversible step—often a spike branch or preview deployment—and define one success signal (e.g. p75 LCP, build time, DX survey). For drill #27, I call out risks (lock-in, complexity, training) and mitigations (abstraction layers, coding standards, ADRs). I avoid absolutes: Next fits when routing + rendering + deployment integration reduce total cost versus bolting libraries onto React alone.
// app/dashboard/layout.tsx
export default function DashboardLayout({ children }: { children: React.ReactNode }) {
return (
<div className="flex">
<aside>Nav</aside>
<section>{children}</section>
</div>
);
}
E028 — Drill 28: Metadata API in layout vs page precedence.
Scenario: Metadata API in layout vs page precedence. (variation 28: assume App Router, TypeScript, and a product team shipping weekly.)
Prompt: What decision do you make, what do you document, and what metric or artifact proves the outcome for case #28?
Model answer: I restate constraints (team size, SEO needs, deploy target, latency budget). I pick the smallest reversible step—often a spike branch or preview deployment—and define one success signal (e.g. p75 LCP, build time, DX survey). For drill #28, I call out risks (lock-in, complexity, training) and mitigations (abstraction layers, coding standards, ADRs). I avoid absolutes: Next fits when routing + rendering + deployment integration reduce total cost versus bolting libraries onto React alone.
// app/dashboard/layout.tsx
export default function DashboardLayout({ children }: { children: React.ReactNode }) {
return (
<div className="flex">
<aside>Nav</aside>
<section>{children}</section>
</div>
);
}
E029 — Drill 29: Avoiding duplicate headers across nested layouts.
Scenario: Avoiding duplicate headers across nested layouts. (variation 29: assume App Router, TypeScript, and a product team shipping weekly.)
Prompt: What decision do you make, what do you document, and what metric or artifact proves the outcome for case #29?
Model answer: I restate constraints (team size, SEO needs, deploy target, latency budget). I pick the smallest reversible step—often a spike branch or preview deployment—and define one success signal (e.g. p75 LCP, build time, DX survey). For drill #29, I call out risks (lock-in, complexity, training) and mitigations (abstraction layers, coding standards, ADRs). I avoid absolutes: Next fits when routing + rendering + deployment integration reduce total cost versus bolting libraries onto React alone.
// app/dashboard/layout.tsx
export default function DashboardLayout({ children }: { children: React.ReactNode }) {
return (
<div className="flex">
<aside>Nav</aside>
<section>{children}</section>
</div>
);
}
E030 — Drill 30: Migrating Pages Router _app global layout to App Router.
Scenario: Migrating Pages Router _app global layout to App Router. (variation 30: assume App Router, TypeScript, and a product team shipping weekly.)
Prompt: What decision do you make, what do you document, and what metric or artifact proves the outcome for case #30?
Model answer: I restate constraints (team size, SEO needs, deploy target, latency budget). I pick the smallest reversible step—often a spike branch or preview deployment—and define one success signal (e.g. p75 LCP, build time, DX survey). For drill #30, I call out risks (lock-in, complexity, training) and mitigations (abstraction layers, coding standards, ADRs). I avoid absolutes: Next fits when routing + rendering + deployment integration reduce total cost versus bolting libraries onto React alone.
// app/dashboard/layout.tsx
export default function DashboardLayout({ children }: { children: React.ReactNode }) {
return (
<div className="flex">
<aside>Nav</aside>
<section>{children}</section>
</div>
);
}
E031 — Drill 31: Root layout must include <html> and <body>.
Scenario: Root layout must include <html> and <body>. (variation 31: assume App Router, TypeScript, and a product team shipping weekly.)
Prompt: What decision do you make, what do you document, and what metric or artifact proves the outcome for case #31?
Model answer: I restate constraints (team size, SEO needs, deploy target, latency budget). I pick the smallest reversible step—often a spike branch or preview deployment—and define one success signal (e.g. p75 LCP, build time, DX survey). For drill #31, I call out risks (lock-in, complexity, training) and mitigations (abstraction layers, coding standards, ADRs). I avoid absolutes: Next fits when routing + rendering + deployment integration reduce total cost versus bolting libraries onto React alone.
// app/dashboard/layout.tsx
export default function DashboardLayout({ children }: { children: React.ReactNode }) {
return (
<div className="flex">
<aside>Nav</aside>
<section>{children}</section>
</div>
);
}
E032 — Drill 32: Nested layout adds sidebar only for /dashboard subtree.
Scenario: Nested layout adds sidebar only for /dashboard subtree. (variation 32: assume App Router, TypeScript, and a product team shipping weekly.)
Prompt: What decision do you make, what do you document, and what metric or artifact proves the outcome for case #32?
Model answer: I restate constraints (team size, SEO needs, deploy target, latency budget). I pick the smallest reversible step—often a spike branch or preview deployment—and define one success signal (e.g. p75 LCP, build time, DX survey). For drill #32, I call out risks (lock-in, complexity, training) and mitigations (abstraction layers, coding standards, ADRs). I avoid absolutes: Next fits when routing + rendering + deployment integration reduce total cost versus bolting libraries onto React alone.
// app/dashboard/layout.tsx
export default function DashboardLayout({ children }: { children: React.ReactNode }) {
return (
<div className="flex">
<aside>Nav</aside>
<section>{children}</section>
</div>
);
}
E033 — Drill 33: Layout vs template re-mount behavior difference.
Scenario: Layout vs template re-mount behavior difference. (variation 33: assume App Router, TypeScript, and a product team shipping weekly.)
Prompt: What decision do you make, what do you document, and what metric or artifact proves the outcome for case #33?
Model answer: I restate constraints (team size, SEO needs, deploy target, latency budget). I pick the smallest reversible step—often a spike branch or preview deployment—and define one success signal (e.g. p75 LCP, build time, DX survey). For drill #33, I call out risks (lock-in, complexity, training) and mitigations (abstraction layers, coding standards, ADRs). I avoid absolutes: Next fits when routing + rendering + deployment integration reduce total cost versus bolting libraries onto React alone.
// app/dashboard/layout.tsx
export default function DashboardLayout({ children }: { children: React.ReactNode }) {
return (
<div className="flex">
<aside>Nav</aside>
<section>{children}</section>
</div>
);
}
E034 — Drill 34: Loading.tsx skeleton hierarchy per segment.
Scenario: Loading.tsx skeleton hierarchy per segment. (variation 34: assume App Router, TypeScript, and a product team shipping weekly.)
Prompt: What decision do you make, what do you document, and what metric or artifact proves the outcome for case #34?
Model answer: I restate constraints (team size, SEO needs, deploy target, latency budget). I pick the smallest reversible step—often a spike branch or preview deployment—and define one success signal (e.g. p75 LCP, build time, DX survey). For drill #34, I call out risks (lock-in, complexity, training) and mitigations (abstraction layers, coding standards, ADRs). I avoid absolutes: Next fits when routing + rendering + deployment integration reduce total cost versus bolting libraries onto React alone.
// app/dashboard/layout.tsx
export default function DashboardLayout({ children }: { children: React.ReactNode }) {
return (
<div className="flex">
<aside>Nav</aside>
<section>{children}</section>
</div>
);
}
E035 — Drill 35: Error.tsx boundary scope for segment failures.
Scenario: Error.tsx boundary scope for segment failures. (variation 35: assume App Router, TypeScript, and a product team shipping weekly.)
Prompt: What decision do you make, what do you document, and what metric or artifact proves the outcome for case #35?
Model answer: I restate constraints (team size, SEO needs, deploy target, latency budget). I pick the smallest reversible step—often a spike branch or preview deployment—and define one success signal (e.g. p75 LCP, build time, DX survey). For drill #35, I call out risks (lock-in, complexity, training) and mitigations (abstraction layers, coding standards, ADRs). I avoid absolutes: Next fits when routing + rendering + deployment integration reduce total cost versus bolting libraries onto React alone.
// app/dashboard/layout.tsx
export default function DashboardLayout({ children }: { children: React.ReactNode }) {
return (
<div className="flex">
<aside>Nav</aside>
<section>{children}</section>
</div>
);
}
E036 — Drill 36: Multiple children slots in parallel routes layout.
Scenario: Multiple children slots in parallel routes layout. (variation 36: assume App Router, TypeScript, and a product team shipping weekly.)
Prompt: What decision do you make, what do you document, and what metric or artifact proves the outcome for case #36?
Model answer: I restate constraints (team size, SEO needs, deploy target, latency budget). I pick the smallest reversible step—often a spike branch or preview deployment—and define one success signal (e.g. p75 LCP, build time, DX survey). For drill #36, I call out risks (lock-in, complexity, training) and mitigations (abstraction layers, coding standards, ADRs). I avoid absolutes: Next fits when routing + rendering + deployment integration reduce total cost versus bolting libraries onto React alone.
// app/dashboard/layout.tsx
export default function DashboardLayout({ children }: { children: React.ReactNode }) {
return (
<div className="flex">
<aside>Nav</aside>
<section>{children}</section>
</div>
);
}
E037 — Drill 37: Font optimization via next/font in root layout.
Scenario: Font optimization via next/font in root layout. (variation 37: assume App Router, TypeScript, and a product team shipping weekly.)
Prompt: What decision do you make, what do you document, and what metric or artifact proves the outcome for case #37?
Model answer: I restate constraints (team size, SEO needs, deploy target, latency budget). I pick the smallest reversible step—often a spike branch or preview deployment—and define one success signal (e.g. p75 LCP, build time, DX survey). For drill #37, I call out risks (lock-in, complexity, training) and mitigations (abstraction layers, coding standards, ADRs). I avoid absolutes: Next fits when routing + rendering + deployment integration reduce total cost versus bolting libraries onto React alone.
// app/dashboard/layout.tsx
export default function DashboardLayout({ children }: { children: React.ReactNode }) {
return (
<div className="flex">
<aside>Nav</aside>
<section>{children}</section>
</div>
);
}
E038 — Drill 38: Metadata API in layout vs page precedence.
Scenario: Metadata API in layout vs page precedence. (variation 38: assume App Router, TypeScript, and a product team shipping weekly.)
Prompt: What decision do you make, what do you document, and what metric or artifact proves the outcome for case #38?
Model answer: I restate constraints (team size, SEO needs, deploy target, latency budget). I pick the smallest reversible step—often a spike branch or preview deployment—and define one success signal (e.g. p75 LCP, build time, DX survey). For drill #38, I call out risks (lock-in, complexity, training) and mitigations (abstraction layers, coding standards, ADRs). I avoid absolutes: Next fits when routing + rendering + deployment integration reduce total cost versus bolting libraries onto React alone.
// app/dashboard/layout.tsx
export default function DashboardLayout({ children }: { children: React.ReactNode }) {
return (
<div className="flex">
<aside>Nav</aside>
<section>{children}</section>
</div>
);
}
E039 — Drill 39: Avoiding duplicate headers across nested layouts.
Scenario: Avoiding duplicate headers across nested layouts. (variation 39: assume App Router, TypeScript, and a product team shipping weekly.)
Prompt: What decision do you make, what do you document, and what metric or artifact proves the outcome for case #39?
Model answer: I restate constraints (team size, SEO needs, deploy target, latency budget). I pick the smallest reversible step—often a spike branch or preview deployment—and define one success signal (e.g. p75 LCP, build time, DX survey). For drill #39, I call out risks (lock-in, complexity, training) and mitigations (abstraction layers, coding standards, ADRs). I avoid absolutes: Next fits when routing + rendering + deployment integration reduce total cost versus bolting libraries onto React alone.
// app/dashboard/layout.tsx
export default function DashboardLayout({ children }: { children: React.ReactNode }) {
return (
<div className="flex">
<aside>Nav</aside>
<section>{children}</section>
</div>
);
}
E040 — Drill 40: Migrating Pages Router _app global layout to App Router.
Scenario: Migrating Pages Router _app global layout to App Router. (variation 40: assume App Router, TypeScript, and a product team shipping weekly.)
Prompt: What decision do you make, what do you document, and what metric or artifact proves the outcome for case #40?
Model answer: I restate constraints (team size, SEO needs, deploy target, latency budget). I pick the smallest reversible step—often a spike branch or preview deployment—and define one success signal (e.g. p75 LCP, build time, DX survey). For drill #40, I call out risks (lock-in, complexity, training) and mitigations (abstraction layers, coding standards, ADRs). I avoid absolutes: Next fits when routing + rendering + deployment integration reduce total cost versus bolting libraries onto React alone.
// app/dashboard/layout.tsx
export default function DashboardLayout({ children }: { children: React.ReactNode }) {
return (
<div className="flex">
<aside>Nav</aside>
<section>{children}</section>
</div>
);
}
E041 — Drill 41: Root layout must include <html> and <body>.
Scenario: Root layout must include <html> and <body>. (variation 41: assume App Router, TypeScript, and a product team shipping weekly.)
Prompt: What decision do you make, what do you document, and what metric or artifact proves the outcome for case #41?
Model answer: I restate constraints (team size, SEO needs, deploy target, latency budget). I pick the smallest reversible step—often a spike branch or preview deployment—and define one success signal (e.g. p75 LCP, build time, DX survey). For drill #41, I call out risks (lock-in, complexity, training) and mitigations (abstraction layers, coding standards, ADRs). I avoid absolutes: Next fits when routing + rendering + deployment integration reduce total cost versus bolting libraries onto React alone.
// app/dashboard/layout.tsx
export default function DashboardLayout({ children }: { children: React.ReactNode }) {
return (
<div className="flex">
<aside>Nav</aside>
<section>{children}</section>
</div>
);
}
E042 — Drill 42: Nested layout adds sidebar only for /dashboard subtree.
Scenario: Nested layout adds sidebar only for /dashboard subtree. (variation 42: assume App Router, TypeScript, and a product team shipping weekly.)
Prompt: What decision do you make, what do you document, and what metric or artifact proves the outcome for case #42?
Model answer: I restate constraints (team size, SEO needs, deploy target, latency budget). I pick the smallest reversible step—often a spike branch or preview deployment—and define one success signal (e.g. p75 LCP, build time, DX survey). For drill #42, I call out risks (lock-in, complexity, training) and mitigations (abstraction layers, coding standards, ADRs). I avoid absolutes: Next fits when routing + rendering + deployment integration reduce total cost versus bolting libraries onto React alone.
// app/dashboard/layout.tsx
export default function DashboardLayout({ children }: { children: React.ReactNode }) {
return (
<div className="flex">
<aside>Nav</aside>
<section>{children}</section>
</div>
);
}
E043 — Drill 43: Layout vs template re-mount behavior difference.
Scenario: Layout vs template re-mount behavior difference. (variation 43: assume App Router, TypeScript, and a product team shipping weekly.)
Prompt: What decision do you make, what do you document, and what metric or artifact proves the outcome for case #43?
Model answer: I restate constraints (team size, SEO needs, deploy target, latency budget). I pick the smallest reversible step—often a spike branch or preview deployment—and define one success signal (e.g. p75 LCP, build time, DX survey). For drill #43, I call out risks (lock-in, complexity, training) and mitigations (abstraction layers, coding standards, ADRs). I avoid absolutes: Next fits when routing + rendering + deployment integration reduce total cost versus bolting libraries onto React alone.
// app/dashboard/layout.tsx
export default function DashboardLayout({ children }: { children: React.ReactNode }) {
return (
<div className="flex">
<aside>Nav</aside>
<section>{children}</section>
</div>
);
}
E044 — Drill 44: Loading.tsx skeleton hierarchy per segment.
Scenario: Loading.tsx skeleton hierarchy per segment. (variation 44: assume App Router, TypeScript, and a product team shipping weekly.)
Prompt: What decision do you make, what do you document, and what metric or artifact proves the outcome for case #44?
Model answer: I restate constraints (team size, SEO needs, deploy target, latency budget). I pick the smallest reversible step—often a spike branch or preview deployment—and define one success signal (e.g. p75 LCP, build time, DX survey). For drill #44, I call out risks (lock-in, complexity, training) and mitigations (abstraction layers, coding standards, ADRs). I avoid absolutes: Next fits when routing + rendering + deployment integration reduce total cost versus bolting libraries onto React alone.
// app/dashboard/layout.tsx
export default function DashboardLayout({ children }: { children: React.ReactNode }) {
return (
<div className="flex">
<aside>Nav</aside>
<section>{children}</section>
</div>
);
}
E045 — Drill 45: Error.tsx boundary scope for segment failures.
Scenario: Error.tsx boundary scope for segment failures. (variation 45: assume App Router, TypeScript, and a product team shipping weekly.)
Prompt: What decision do you make, what do you document, and what metric or artifact proves the outcome for case #45?
Model answer: I restate constraints (team size, SEO needs, deploy target, latency budget). I pick the smallest reversible step—often a spike branch or preview deployment—and define one success signal (e.g. p75 LCP, build time, DX survey). For drill #45, I call out risks (lock-in, complexity, training) and mitigations (abstraction layers, coding standards, ADRs). I avoid absolutes: Next fits when routing + rendering + deployment integration reduce total cost versus bolting libraries onto React alone.
// app/dashboard/layout.tsx
export default function DashboardLayout({ children }: { children: React.ReactNode }) {
return (
<div className="flex">
<aside>Nav</aside>
<section>{children}</section>
</div>
);
}
E046 — Drill 46: Multiple children slots in parallel routes layout.
Scenario: Multiple children slots in parallel routes layout. (variation 46: assume App Router, TypeScript, and a product team shipping weekly.)
Prompt: What decision do you make, what do you document, and what metric or artifact proves the outcome for case #46?
Model answer: I restate constraints (team size, SEO needs, deploy target, latency budget). I pick the smallest reversible step—often a spike branch or preview deployment—and define one success signal (e.g. p75 LCP, build time, DX survey). For drill #46, I call out risks (lock-in, complexity, training) and mitigations (abstraction layers, coding standards, ADRs). I avoid absolutes: Next fits when routing + rendering + deployment integration reduce total cost versus bolting libraries onto React alone.
// app/dashboard/layout.tsx
export default function DashboardLayout({ children }: { children: React.ReactNode }) {
return (
<div className="flex">
<aside>Nav</aside>
<section>{children}</section>
</div>
);
}
E047 — Drill 47: Font optimization via next/font in root layout.
Scenario: Font optimization via next/font in root layout. (variation 47: assume App Router, TypeScript, and a product team shipping weekly.)
Prompt: What decision do you make, what do you document, and what metric or artifact proves the outcome for case #47?
Model answer: I restate constraints (team size, SEO needs, deploy target, latency budget). I pick the smallest reversible step—often a spike branch or preview deployment—and define one success signal (e.g. p75 LCP, build time, DX survey). For drill #47, I call out risks (lock-in, complexity, training) and mitigations (abstraction layers, coding standards, ADRs). I avoid absolutes: Next fits when routing + rendering + deployment integration reduce total cost versus bolting libraries onto React alone.
// app/dashboard/layout.tsx
export default function DashboardLayout({ children }: { children: React.ReactNode }) {
return (
<div className="flex">
<aside>Nav</aside>
<section>{children}</section>
</div>
);
}
E048 — Drill 48: Metadata API in layout vs page precedence.
Scenario: Metadata API in layout vs page precedence. (variation 48: assume App Router, TypeScript, and a product team shipping weekly.)
Prompt: What decision do you make, what do you document, and what metric or artifact proves the outcome for case #48?
Model answer: I restate constraints (team size, SEO needs, deploy target, latency budget). I pick the smallest reversible step—often a spike branch or preview deployment—and define one success signal (e.g. p75 LCP, build time, DX survey). For drill #48, I call out risks (lock-in, complexity, training) and mitigations (abstraction layers, coding standards, ADRs). I avoid absolutes: Next fits when routing + rendering + deployment integration reduce total cost versus bolting libraries onto React alone.
// app/dashboard/layout.tsx
export default function DashboardLayout({ children }: { children: React.ReactNode }) {
return (
<div className="flex">
<aside>Nav</aside>
<section>{children}</section>
</div>
);
}
E049 — Drill 49: Avoiding duplicate headers across nested layouts.
Scenario: Avoiding duplicate headers across nested layouts. (variation 49: assume App Router, TypeScript, and a product team shipping weekly.)
Prompt: What decision do you make, what do you document, and what metric or artifact proves the outcome for case #49?
Model answer: I restate constraints (team size, SEO needs, deploy target, latency budget). I pick the smallest reversible step—often a spike branch or preview deployment—and define one success signal (e.g. p75 LCP, build time, DX survey). For drill #49, I call out risks (lock-in, complexity, training) and mitigations (abstraction layers, coding standards, ADRs). I avoid absolutes: Next fits when routing + rendering + deployment integration reduce total cost versus bolting libraries onto React alone.
// app/dashboard/layout.tsx
export default function DashboardLayout({ children }: { children: React.ReactNode }) {
return (
<div className="flex">
<aside>Nav</aside>
<section>{children}</section>
</div>
);
}
E050 — Drill 50: Migrating Pages Router _app global layout to App Router.
Scenario: Migrating Pages Router _app global layout to App Router. (variation 50: assume App Router, TypeScript, and a product team shipping weekly.)
Prompt: What decision do you make, what do you document, and what metric or artifact proves the outcome for case #50?
Model answer: I restate constraints (team size, SEO needs, deploy target, latency budget). I pick the smallest reversible step—often a spike branch or preview deployment—and define one success signal (e.g. p75 LCP, build time, DX survey). For drill #50, I call out risks (lock-in, complexity, training) and mitigations (abstraction layers, coding standards, ADRs). I avoid absolutes: Next fits when routing + rendering + deployment integration reduce total cost versus bolting libraries onto React alone.
// app/dashboard/layout.tsx
export default function DashboardLayout({ children }: { children: React.ReactNode }) {
return (
<div className="flex">
<aside>Nav</aside>
<section>{children}</section>
</div>
);
}
E051 — Drill 51: Root layout must include <html> and <body>.
Scenario: Root layout must include <html> and <body>. (variation 51: assume App Router, TypeScript, and a product team shipping weekly.)
Prompt: What decision do you make, what do you document, and what metric or artifact proves the outcome for case #51?
Model answer: I restate constraints (team size, SEO needs, deploy target, latency budget). I pick the smallest reversible step—often a spike branch or preview deployment—and define one success signal (e.g. p75 LCP, build time, DX survey). For drill #51, I call out risks (lock-in, complexity, training) and mitigations (abstraction layers, coding standards, ADRs). I avoid absolutes: Next fits when routing + rendering + deployment integration reduce total cost versus bolting libraries onto React alone.
// app/dashboard/layout.tsx
export default function DashboardLayout({ children }: { children: React.ReactNode }) {
return (
<div className="flex">
<aside>Nav</aside>
<section>{children}</section>
</div>
);
}
E052 — Drill 52: Nested layout adds sidebar only for /dashboard subtree.
Scenario: Nested layout adds sidebar only for /dashboard subtree. (variation 52: assume App Router, TypeScript, and a product team shipping weekly.)
Prompt: What decision do you make, what do you document, and what metric or artifact proves the outcome for case #52?
Model answer: I restate constraints (team size, SEO needs, deploy target, latency budget). I pick the smallest reversible step—often a spike branch or preview deployment—and define one success signal (e.g. p75 LCP, build time, DX survey). For drill #52, I call out risks (lock-in, complexity, training) and mitigations (abstraction layers, coding standards, ADRs). I avoid absolutes: Next fits when routing + rendering + deployment integration reduce total cost versus bolting libraries onto React alone.
// app/dashboard/layout.tsx
export default function DashboardLayout({ children }: { children: React.ReactNode }) {
return (
<div className="flex">
<aside>Nav</aside>
<section>{children}</section>
</div>
);
}
E053 — Drill 53: Layout vs template re-mount behavior difference.
Scenario: Layout vs template re-mount behavior difference. (variation 53: assume App Router, TypeScript, and a product team shipping weekly.)
Prompt: What decision do you make, what do you document, and what metric or artifact proves the outcome for case #53?
Model answer: I restate constraints (team size, SEO needs, deploy target, latency budget). I pick the smallest reversible step—often a spike branch or preview deployment—and define one success signal (e.g. p75 LCP, build time, DX survey). For drill #53, I call out risks (lock-in, complexity, training) and mitigations (abstraction layers, coding standards, ADRs). I avoid absolutes: Next fits when routing + rendering + deployment integration reduce total cost versus bolting libraries onto React alone.
// app/dashboard/layout.tsx
export default function DashboardLayout({ children }: { children: React.ReactNode }) {
return (
<div className="flex">
<aside>Nav</aside>
<section>{children}</section>
</div>
);
}
E054 — Drill 54: Loading.tsx skeleton hierarchy per segment.
Scenario: Loading.tsx skeleton hierarchy per segment. (variation 54: assume App Router, TypeScript, and a product team shipping weekly.)
Prompt: What decision do you make, what do you document, and what metric or artifact proves the outcome for case #54?
Model answer: I restate constraints (team size, SEO needs, deploy target, latency budget). I pick the smallest reversible step—often a spike branch or preview deployment—and define one success signal (e.g. p75 LCP, build time, DX survey). For drill #54, I call out risks (lock-in, complexity, training) and mitigations (abstraction layers, coding standards, ADRs). I avoid absolutes: Next fits when routing + rendering + deployment integration reduce total cost versus bolting libraries onto React alone.
// app/dashboard/layout.tsx
export default function DashboardLayout({ children }: { children: React.ReactNode }) {
return (
<div className="flex">
<aside>Nav</aside>
<section>{children}</section>
</div>
);
}
E055 — Drill 55: Error.tsx boundary scope for segment failures.
Scenario: Error.tsx boundary scope for segment failures. (variation 55: assume App Router, TypeScript, and a product team shipping weekly.)
Prompt: What decision do you make, what do you document, and what metric or artifact proves the outcome for case #55?
Model answer: I restate constraints (team size, SEO needs, deploy target, latency budget). I pick the smallest reversible step—often a spike branch or preview deployment—and define one success signal (e.g. p75 LCP, build time, DX survey). For drill #55, I call out risks (lock-in, complexity, training) and mitigations (abstraction layers, coding standards, ADRs). I avoid absolutes: Next fits when routing + rendering + deployment integration reduce total cost versus bolting libraries onto React alone.
// app/dashboard/layout.tsx
export default function DashboardLayout({ children }: { children: React.ReactNode }) {
return (
<div className="flex">
<aside>Nav</aside>
<section>{children}</section>
</div>
);
}
E056 — Drill 56: Multiple children slots in parallel routes layout.
Scenario: Multiple children slots in parallel routes layout. (variation 56: assume App Router, TypeScript, and a product team shipping weekly.)
Prompt: What decision do you make, what do you document, and what metric or artifact proves the outcome for case #56?
Model answer: I restate constraints (team size, SEO needs, deploy target, latency budget). I pick the smallest reversible step—often a spike branch or preview deployment—and define one success signal (e.g. p75 LCP, build time, DX survey). For drill #56, I call out risks (lock-in, complexity, training) and mitigations (abstraction layers, coding standards, ADRs). I avoid absolutes: Next fits when routing + rendering + deployment integration reduce total cost versus bolting libraries onto React alone.
// app/dashboard/layout.tsx
export default function DashboardLayout({ children }: { children: React.ReactNode }) {
return (
<div className="flex">
<aside>Nav</aside>
<section>{children}</section>
</div>
);
}
E057 — Drill 57: Font optimization via next/font in root layout.
Scenario: Font optimization via next/font in root layout. (variation 57: assume App Router, TypeScript, and a product team shipping weekly.)
Prompt: What decision do you make, what do you document, and what metric or artifact proves the outcome for case #57?
Model answer: I restate constraints (team size, SEO needs, deploy target, latency budget). I pick the smallest reversible step—often a spike branch or preview deployment—and define one success signal (e.g. p75 LCP, build time, DX survey). For drill #57, I call out risks (lock-in, complexity, training) and mitigations (abstraction layers, coding standards, ADRs). I avoid absolutes: Next fits when routing + rendering + deployment integration reduce total cost versus bolting libraries onto React alone.
// app/dashboard/layout.tsx
export default function DashboardLayout({ children }: { children: React.ReactNode }) {
return (
<div className="flex">
<aside>Nav</aside>
<section>{children}</section>
</div>
);
}
E058 — Drill 58: Metadata API in layout vs page precedence.
Scenario: Metadata API in layout vs page precedence. (variation 58: assume App Router, TypeScript, and a product team shipping weekly.)
Prompt: What decision do you make, what do you document, and what metric or artifact proves the outcome for case #58?
Model answer: I restate constraints (team size, SEO needs, deploy target, latency budget). I pick the smallest reversible step—often a spike branch or preview deployment—and define one success signal (e.g. p75 LCP, build time, DX survey). For drill #58, I call out risks (lock-in, complexity, training) and mitigations (abstraction layers, coding standards, ADRs). I avoid absolutes: Next fits when routing + rendering + deployment integration reduce total cost versus bolting libraries onto React alone.
// app/dashboard/layout.tsx
export default function DashboardLayout({ children }: { children: React.ReactNode }) {
return (
<div className="flex">
<aside>Nav</aside>
<section>{children}</section>
</div>
);
}
E059 — Drill 59: Avoiding duplicate headers across nested layouts.
Scenario: Avoiding duplicate headers across nested layouts. (variation 59: assume App Router, TypeScript, and a product team shipping weekly.)
Prompt: What decision do you make, what do you document, and what metric or artifact proves the outcome for case #59?
Model answer: I restate constraints (team size, SEO needs, deploy target, latency budget). I pick the smallest reversible step—often a spike branch or preview deployment—and define one success signal (e.g. p75 LCP, build time, DX survey). For drill #59, I call out risks (lock-in, complexity, training) and mitigations (abstraction layers, coding standards, ADRs). I avoid absolutes: Next fits when routing + rendering + deployment integration reduce total cost versus bolting libraries onto React alone.
// app/dashboard/layout.tsx
export default function DashboardLayout({ children }: { children: React.ReactNode }) {
return (
<div className="flex">
<aside>Nav</aside>
<section>{children}</section>
</div>
);
}
E060 — Drill 60: Migrating Pages Router _app global layout to App Router.
Scenario: Migrating Pages Router _app global layout to App Router. (variation 60: assume App Router, TypeScript, and a product team shipping weekly.)
Prompt: What decision do you make, what do you document, and what metric or artifact proves the outcome for case #60?
Model answer: I restate constraints (team size, SEO needs, deploy target, latency budget). I pick the smallest reversible step—often a spike branch or preview deployment—and define one success signal (e.g. p75 LCP, build time, DX survey). For drill #60, I call out risks (lock-in, complexity, training) and mitigations (abstraction layers, coding standards, ADRs). I avoid absolutes: Next fits when routing + rendering + deployment integration reduce total cost versus bolting libraries onto React alone.
// app/dashboard/layout.tsx
export default function DashboardLayout({ children }: { children: React.ReactNode }) {
return (
<div className="flex">
<aside>Nav</aside>
<section>{children}</section>
</div>
);
}
E061 — Drill 61: Root layout must include <html> and <body>.
Scenario: Root layout must include <html> and <body>. (variation 61: assume App Router, TypeScript, and a product team shipping weekly.)
Prompt: What decision do you make, what do you document, and what metric or artifact proves the outcome for case #61?
Model answer: I restate constraints (team size, SEO needs, deploy target, latency budget). I pick the smallest reversible step—often a spike branch or preview deployment—and define one success signal (e.g. p75 LCP, build time, DX survey). For drill #61, I call out risks (lock-in, complexity, training) and mitigations (abstraction layers, coding standards, ADRs). I avoid absolutes: Next fits when routing + rendering + deployment integration reduce total cost versus bolting libraries onto React alone.
// app/dashboard/layout.tsx
export default function DashboardLayout({ children }: { children: React.ReactNode }) {
return (
<div className="flex">
<aside>Nav</aside>
<section>{children}</section>
</div>
);
}
E062 — Drill 62: Nested layout adds sidebar only for /dashboard subtree.
Scenario: Nested layout adds sidebar only for /dashboard subtree. (variation 62: assume App Router, TypeScript, and a product team shipping weekly.)
Prompt: What decision do you make, what do you document, and what metric or artifact proves the outcome for case #62?
Model answer: I restate constraints (team size, SEO needs, deploy target, latency budget). I pick the smallest reversible step—often a spike branch or preview deployment—and define one success signal (e.g. p75 LCP, build time, DX survey). For drill #62, I call out risks (lock-in, complexity, training) and mitigations (abstraction layers, coding standards, ADRs). I avoid absolutes: Next fits when routing + rendering + deployment integration reduce total cost versus bolting libraries onto React alone.
// app/dashboard/layout.tsx
export default function DashboardLayout({ children }: { children: React.ReactNode }) {
return (
<div className="flex">
<aside>Nav</aside>
<section>{children}</section>
</div>
);
}
E063 — Drill 63: Layout vs template re-mount behavior difference.
Scenario: Layout vs template re-mount behavior difference. (variation 63: assume App Router, TypeScript, and a product team shipping weekly.)
Prompt: What decision do you make, what do you document, and what metric or artifact proves the outcome for case #63?
Model answer: I restate constraints (team size, SEO needs, deploy target, latency budget). I pick the smallest reversible step—often a spike branch or preview deployment—and define one success signal (e.g. p75 LCP, build time, DX survey). For drill #63, I call out risks (lock-in, complexity, training) and mitigations (abstraction layers, coding standards, ADRs). I avoid absolutes: Next fits when routing + rendering + deployment integration reduce total cost versus bolting libraries onto React alone.
// app/dashboard/layout.tsx
export default function DashboardLayout({ children }: { children: React.ReactNode }) {
return (
<div className="flex">
<aside>Nav</aside>
<section>{children}</section>
</div>
);
}
E064 — Drill 64: Loading.tsx skeleton hierarchy per segment.
Scenario: Loading.tsx skeleton hierarchy per segment. (variation 64: assume App Router, TypeScript, and a product team shipping weekly.)
Prompt: What decision do you make, what do you document, and what metric or artifact proves the outcome for case #64?
Model answer: I restate constraints (team size, SEO needs, deploy target, latency budget). I pick the smallest reversible step—often a spike branch or preview deployment—and define one success signal (e.g. p75 LCP, build time, DX survey). For drill #64, I call out risks (lock-in, complexity, training) and mitigations (abstraction layers, coding standards, ADRs). I avoid absolutes: Next fits when routing + rendering + deployment integration reduce total cost versus bolting libraries onto React alone.
// app/dashboard/layout.tsx
export default function DashboardLayout({ children }: { children: React.ReactNode }) {
return (
<div className="flex">
<aside>Nav</aside>
<section>{children}</section>
</div>
);
}
E065 — Drill 65: Error.tsx boundary scope for segment failures.
Scenario: Error.tsx boundary scope for segment failures. (variation 65: assume App Router, TypeScript, and a product team shipping weekly.)
Prompt: What decision do you make, what do you document, and what metric or artifact proves the outcome for case #65?
Model answer: I restate constraints (team size, SEO needs, deploy target, latency budget). I pick the smallest reversible step—often a spike branch or preview deployment—and define one success signal (e.g. p75 LCP, build time, DX survey). For drill #65, I call out risks (lock-in, complexity, training) and mitigations (abstraction layers, coding standards, ADRs). I avoid absolutes: Next fits when routing + rendering + deployment integration reduce total cost versus bolting libraries onto React alone.
// app/dashboard/layout.tsx
export default function DashboardLayout({ children }: { children: React.ReactNode }) {
return (
<div className="flex">
<aside>Nav</aside>
<section>{children}</section>
</div>
);
}
E066 — Drill 66: Multiple children slots in parallel routes layout.
Scenario: Multiple children slots in parallel routes layout. (variation 66: assume App Router, TypeScript, and a product team shipping weekly.)
Prompt: What decision do you make, what do you document, and what metric or artifact proves the outcome for case #66?
Model answer: I restate constraints (team size, SEO needs, deploy target, latency budget). I pick the smallest reversible step—often a spike branch or preview deployment—and define one success signal (e.g. p75 LCP, build time, DX survey). For drill #66, I call out risks (lock-in, complexity, training) and mitigations (abstraction layers, coding standards, ADRs). I avoid absolutes: Next fits when routing + rendering + deployment integration reduce total cost versus bolting libraries onto React alone.
// app/dashboard/layout.tsx
export default function DashboardLayout({ children }: { children: React.ReactNode }) {
return (
<div className="flex">
<aside>Nav</aside>
<section>{children}</section>
</div>
);
}
E067 — Drill 67: Font optimization via next/font in root layout.
Scenario: Font optimization via next/font in root layout. (variation 67: assume App Router, TypeScript, and a product team shipping weekly.)
Prompt: What decision do you make, what do you document, and what metric or artifact proves the outcome for case #67?
Model answer: I restate constraints (team size, SEO needs, deploy target, latency budget). I pick the smallest reversible step—often a spike branch or preview deployment—and define one success signal (e.g. p75 LCP, build time, DX survey). For drill #67, I call out risks (lock-in, complexity, training) and mitigations (abstraction layers, coding standards, ADRs). I avoid absolutes: Next fits when routing + rendering + deployment integration reduce total cost versus bolting libraries onto React alone.
// app/dashboard/layout.tsx
export default function DashboardLayout({ children }: { children: React.ReactNode }) {
return (
<div className="flex">
<aside>Nav</aside>
<section>{children}</section>
</div>
);
}
E068 — Drill 68: Metadata API in layout vs page precedence.
Scenario: Metadata API in layout vs page precedence. (variation 68: assume App Router, TypeScript, and a product team shipping weekly.)
Prompt: What decision do you make, what do you document, and what metric or artifact proves the outcome for case #68?
Model answer: I restate constraints (team size, SEO needs, deploy target, latency budget). I pick the smallest reversible step—often a spike branch or preview deployment—and define one success signal (e.g. p75 LCP, build time, DX survey). For drill #68, I call out risks (lock-in, complexity, training) and mitigations (abstraction layers, coding standards, ADRs). I avoid absolutes: Next fits when routing + rendering + deployment integration reduce total cost versus bolting libraries onto React alone.
// app/dashboard/layout.tsx
export default function DashboardLayout({ children }: { children: React.ReactNode }) {
return (
<div className="flex">
<aside>Nav</aside>
<section>{children}</section>
</div>
);
}
E069 — Drill 69: Avoiding duplicate headers across nested layouts.
Scenario: Avoiding duplicate headers across nested layouts. (variation 69: assume App Router, TypeScript, and a product team shipping weekly.)
Prompt: What decision do you make, what do you document, and what metric or artifact proves the outcome for case #69?
Model answer: I restate constraints (team size, SEO needs, deploy target, latency budget). I pick the smallest reversible step—often a spike branch or preview deployment—and define one success signal (e.g. p75 LCP, build time, DX survey). For drill #69, I call out risks (lock-in, complexity, training) and mitigations (abstraction layers, coding standards, ADRs). I avoid absolutes: Next fits when routing + rendering + deployment integration reduce total cost versus bolting libraries onto React alone.
// app/dashboard/layout.tsx
export default function DashboardLayout({ children }: { children: React.ReactNode }) {
return (
<div className="flex">
<aside>Nav</aside>
<section>{children}</section>
</div>
);
}
E070 — Drill 70: Migrating Pages Router _app global layout to App Router.
Scenario: Migrating Pages Router _app global layout to App Router. (variation 70: assume App Router, TypeScript, and a product team shipping weekly.)
Prompt: What decision do you make, what do you document, and what metric or artifact proves the outcome for case #70?
Model answer: I restate constraints (team size, SEO needs, deploy target, latency budget). I pick the smallest reversible step—often a spike branch or preview deployment—and define one success signal (e.g. p75 LCP, build time, DX survey). For drill #70, I call out risks (lock-in, complexity, training) and mitigations (abstraction layers, coding standards, ADRs). I avoid absolutes: Next fits when routing + rendering + deployment integration reduce total cost versus bolting libraries onto React alone.
// app/dashboard/layout.tsx
export default function DashboardLayout({ children }: { children: React.ReactNode }) {
return (
<div className="flex">
<aside>Nav</aside>
<section>{children}</section>
</div>
);
}
E071 — Drill 71: Root layout must include <html> and <body>.
Scenario: Root layout must include <html> and <body>. (variation 71: assume App Router, TypeScript, and a product team shipping weekly.)
Prompt: What decision do you make, what do you document, and what metric or artifact proves the outcome for case #71?
Model answer: I restate constraints (team size, SEO needs, deploy target, latency budget). I pick the smallest reversible step—often a spike branch or preview deployment—and define one success signal (e.g. p75 LCP, build time, DX survey). For drill #71, I call out risks (lock-in, complexity, training) and mitigations (abstraction layers, coding standards, ADRs). I avoid absolutes: Next fits when routing + rendering + deployment integration reduce total cost versus bolting libraries onto React alone.
// app/dashboard/layout.tsx
export default function DashboardLayout({ children }: { children: React.ReactNode }) {
return (
<div className="flex">
<aside>Nav</aside>
<section>{children}</section>
</div>
);
}
E072 — Drill 72: Nested layout adds sidebar only for /dashboard subtree.
Scenario: Nested layout adds sidebar only for /dashboard subtree. (variation 72: assume App Router, TypeScript, and a product team shipping weekly.)
Prompt: What decision do you make, what do you document, and what metric or artifact proves the outcome for case #72?
Model answer: I restate constraints (team size, SEO needs, deploy target, latency budget). I pick the smallest reversible step—often a spike branch or preview deployment—and define one success signal (e.g. p75 LCP, build time, DX survey). For drill #72, I call out risks (lock-in, complexity, training) and mitigations (abstraction layers, coding standards, ADRs). I avoid absolutes: Next fits when routing + rendering + deployment integration reduce total cost versus bolting libraries onto React alone.
// app/dashboard/layout.tsx
export default function DashboardLayout({ children }: { children: React.ReactNode }) {
return (
<div className="flex">
<aside>Nav</aside>
<section>{children}</section>
</div>
);
}
E073 — Drill 73: Layout vs template re-mount behavior difference.
Scenario: Layout vs template re-mount behavior difference. (variation 73: assume App Router, TypeScript, and a product team shipping weekly.)
Prompt: What decision do you make, what do you document, and what metric or artifact proves the outcome for case #73?
Model answer: I restate constraints (team size, SEO needs, deploy target, latency budget). I pick the smallest reversible step—often a spike branch or preview deployment—and define one success signal (e.g. p75 LCP, build time, DX survey). For drill #73, I call out risks (lock-in, complexity, training) and mitigations (abstraction layers, coding standards, ADRs). I avoid absolutes: Next fits when routing + rendering + deployment integration reduce total cost versus bolting libraries onto React alone.
// app/dashboard/layout.tsx
export default function DashboardLayout({ children }: { children: React.ReactNode }) {
return (
<div className="flex">
<aside>Nav</aside>
<section>{children}</section>
</div>
);
}
E074 — Drill 74: Loading.tsx skeleton hierarchy per segment.
Scenario: Loading.tsx skeleton hierarchy per segment. (variation 74: assume App Router, TypeScript, and a product team shipping weekly.)
Prompt: What decision do you make, what do you document, and what metric or artifact proves the outcome for case #74?
Model answer: I restate constraints (team size, SEO needs, deploy target, latency budget). I pick the smallest reversible step—often a spike branch or preview deployment—and define one success signal (e.g. p75 LCP, build time, DX survey). For drill #74, I call out risks (lock-in, complexity, training) and mitigations (abstraction layers, coding standards, ADRs). I avoid absolutes: Next fits when routing + rendering + deployment integration reduce total cost versus bolting libraries onto React alone.
// app/dashboard/layout.tsx
export default function DashboardLayout({ children }: { children: React.ReactNode }) {
return (
<div className="flex">
<aside>Nav</aside>
<section>{children}</section>
</div>
);
}
E075 — Drill 75: Error.tsx boundary scope for segment failures.
Scenario: Error.tsx boundary scope for segment failures. (variation 75: assume App Router, TypeScript, and a product team shipping weekly.)
Prompt: What decision do you make, what do you document, and what metric or artifact proves the outcome for case #75?
Model answer: I restate constraints (team size, SEO needs, deploy target, latency budget). I pick the smallest reversible step—often a spike branch or preview deployment—and define one success signal (e.g. p75 LCP, build time, DX survey). For drill #75, I call out risks (lock-in, complexity, training) and mitigations (abstraction layers, coding standards, ADRs). I avoid absolutes: Next fits when routing + rendering + deployment integration reduce total cost versus bolting libraries onto React alone.
// app/dashboard/layout.tsx
export default function DashboardLayout({ children }: { children: React.ReactNode }) {
return (
<div className="flex">
<aside>Nav</aside>
<section>{children}</section>
</div>
);
}
E076 — Drill 76: Multiple children slots in parallel routes layout.
Scenario: Multiple children slots in parallel routes layout. (variation 76: assume App Router, TypeScript, and a product team shipping weekly.)
Prompt: What decision do you make, what do you document, and what metric or artifact proves the outcome for case #76?
Model answer: I restate constraints (team size, SEO needs, deploy target, latency budget). I pick the smallest reversible step—often a spike branch or preview deployment—and define one success signal (e.g. p75 LCP, build time, DX survey). For drill #76, I call out risks (lock-in, complexity, training) and mitigations (abstraction layers, coding standards, ADRs). I avoid absolutes: Next fits when routing + rendering + deployment integration reduce total cost versus bolting libraries onto React alone.
// app/dashboard/layout.tsx
export default function DashboardLayout({ children }: { children: React.ReactNode }) {
return (
<div className="flex">
<aside>Nav</aside>
<section>{children}</section>
</div>
);
}
E077 — Drill 77: Font optimization via next/font in root layout.
Scenario: Font optimization via next/font in root layout. (variation 77: assume App Router, TypeScript, and a product team shipping weekly.)
Prompt: What decision do you make, what do you document, and what metric or artifact proves the outcome for case #77?
Model answer: I restate constraints (team size, SEO needs, deploy target, latency budget). I pick the smallest reversible step—often a spike branch or preview deployment—and define one success signal (e.g. p75 LCP, build time, DX survey). For drill #77, I call out risks (lock-in, complexity, training) and mitigations (abstraction layers, coding standards, ADRs). I avoid absolutes: Next fits when routing + rendering + deployment integration reduce total cost versus bolting libraries onto React alone.
// app/dashboard/layout.tsx
export default function DashboardLayout({ children }: { children: React.ReactNode }) {
return (
<div className="flex">
<aside>Nav</aside>
<section>{children}</section>
</div>
);
}
E078 — Drill 78: Metadata API in layout vs page precedence.
Scenario: Metadata API in layout vs page precedence. (variation 78: assume App Router, TypeScript, and a product team shipping weekly.)
Prompt: What decision do you make, what do you document, and what metric or artifact proves the outcome for case #78?
Model answer: I restate constraints (team size, SEO needs, deploy target, latency budget). I pick the smallest reversible step—often a spike branch or preview deployment—and define one success signal (e.g. p75 LCP, build time, DX survey). For drill #78, I call out risks (lock-in, complexity, training) and mitigations (abstraction layers, coding standards, ADRs). I avoid absolutes: Next fits when routing + rendering + deployment integration reduce total cost versus bolting libraries onto React alone.
// app/dashboard/layout.tsx
export default function DashboardLayout({ children }: { children: React.ReactNode }) {
return (
<div className="flex">
<aside>Nav</aside>
<section>{children}</section>
</div>
);
}
E079 — Drill 79: Avoiding duplicate headers across nested layouts.
Scenario: Avoiding duplicate headers across nested layouts. (variation 79: assume App Router, TypeScript, and a product team shipping weekly.)
Prompt: What decision do you make, what do you document, and what metric or artifact proves the outcome for case #79?
Model answer: I restate constraints (team size, SEO needs, deploy target, latency budget). I pick the smallest reversible step—often a spike branch or preview deployment—and define one success signal (e.g. p75 LCP, build time, DX survey). For drill #79, I call out risks (lock-in, complexity, training) and mitigations (abstraction layers, coding standards, ADRs). I avoid absolutes: Next fits when routing + rendering + deployment integration reduce total cost versus bolting libraries onto React alone.
// app/dashboard/layout.tsx
export default function DashboardLayout({ children }: { children: React.ReactNode }) {
return (
<div className="flex">
<aside>Nav</aside>
<section>{children}</section>
</div>
);
}
E080 — Drill 80: Migrating Pages Router _app global layout to App Router.
Scenario: Migrating Pages Router _app global layout to App Router. (variation 80: assume App Router, TypeScript, and a product team shipping weekly.)
Prompt: What decision do you make, what do you document, and what metric or artifact proves the outcome for case #80?
Model answer: I restate constraints (team size, SEO needs, deploy target, latency budget). I pick the smallest reversible step—often a spike branch or preview deployment—and define one success signal (e.g. p75 LCP, build time, DX survey). For drill #80, I call out risks (lock-in, complexity, training) and mitigations (abstraction layers, coding standards, ADRs). I avoid absolutes: Next fits when routing + rendering + deployment integration reduce total cost versus bolting libraries onto React alone.
// app/dashboard/layout.tsx
export default function DashboardLayout({ children }: { children: React.ReactNode }) {
return (
<div className="flex">
<aside>Nav</aside>
<section>{children}</section>
</div>
);
}
E081 — Drill 81: Root layout must include <html> and <body>.
Scenario: Root layout must include <html> and <body>. (variation 81: assume App Router, TypeScript, and a product team shipping weekly.)
Prompt: What decision do you make, what do you document, and what metric or artifact proves the outcome for case #81?
Model answer: I restate constraints (team size, SEO needs, deploy target, latency budget). I pick the smallest reversible step—often a spike branch or preview deployment—and define one success signal (e.g. p75 LCP, build time, DX survey). For drill #81, I call out risks (lock-in, complexity, training) and mitigations (abstraction layers, coding standards, ADRs). I avoid absolutes: Next fits when routing + rendering + deployment integration reduce total cost versus bolting libraries onto React alone.
// app/dashboard/layout.tsx
export default function DashboardLayout({ children }: { children: React.ReactNode }) {
return (
<div className="flex">
<aside>Nav</aside>
<section>{children}</section>
</div>
);
}
E082 — Drill 82: Nested layout adds sidebar only for /dashboard subtree.
Scenario: Nested layout adds sidebar only for /dashboard subtree. (variation 82: assume App Router, TypeScript, and a product team shipping weekly.)
Prompt: What decision do you make, what do you document, and what metric or artifact proves the outcome for case #82?
Model answer: I restate constraints (team size, SEO needs, deploy target, latency budget). I pick the smallest reversible step—often a spike branch or preview deployment—and define one success signal (e.g. p75 LCP, build time, DX survey). For drill #82, I call out risks (lock-in, complexity, training) and mitigations (abstraction layers, coding standards, ADRs). I avoid absolutes: Next fits when routing + rendering + deployment integration reduce total cost versus bolting libraries onto React alone.
// app/dashboard/layout.tsx
export default function DashboardLayout({ children }: { children: React.ReactNode }) {
return (
<div className="flex">
<aside>Nav</aside>
<section>{children}</section>
</div>
);
}
E083 — Drill 83: Layout vs template re-mount behavior difference.
Scenario: Layout vs template re-mount behavior difference. (variation 83: assume App Router, TypeScript, and a product team shipping weekly.)
Prompt: What decision do you make, what do you document, and what metric or artifact proves the outcome for case #83?
Model answer: I restate constraints (team size, SEO needs, deploy target, latency budget). I pick the smallest reversible step—often a spike branch or preview deployment—and define one success signal (e.g. p75 LCP, build time, DX survey). For drill #83, I call out risks (lock-in, complexity, training) and mitigations (abstraction layers, coding standards, ADRs). I avoid absolutes: Next fits when routing + rendering + deployment integration reduce total cost versus bolting libraries onto React alone.
// app/dashboard/layout.tsx
export default function DashboardLayout({ children }: { children: React.ReactNode }) {
return (
<div className="flex">
<aside>Nav</aside>
<section>{children}</section>
</div>
);
}
E084 — Drill 84: Loading.tsx skeleton hierarchy per segment.
Scenario: Loading.tsx skeleton hierarchy per segment. (variation 84: assume App Router, TypeScript, and a product team shipping weekly.)
Prompt: What decision do you make, what do you document, and what metric or artifact proves the outcome for case #84?
Model answer: I restate constraints (team size, SEO needs, deploy target, latency budget). I pick the smallest reversible step—often a spike branch or preview deployment—and define one success signal (e.g. p75 LCP, build time, DX survey). For drill #84, I call out risks (lock-in, complexity, training) and mitigations (abstraction layers, coding standards, ADRs). I avoid absolutes: Next fits when routing + rendering + deployment integration reduce total cost versus bolting libraries onto React alone.
// app/dashboard/layout.tsx
export default function DashboardLayout({ children }: { children: React.ReactNode }) {
return (
<div className="flex">
<aside>Nav</aside>
<section>{children}</section>
</div>
);
}
E085 — Drill 85: Error.tsx boundary scope for segment failures.
Scenario: Error.tsx boundary scope for segment failures. (variation 85: assume App Router, TypeScript, and a product team shipping weekly.)
Prompt: What decision do you make, what do you document, and what metric or artifact proves the outcome for case #85?
Model answer: I restate constraints (team size, SEO needs, deploy target, latency budget). I pick the smallest reversible step—often a spike branch or preview deployment—and define one success signal (e.g. p75 LCP, build time, DX survey). For drill #85, I call out risks (lock-in, complexity, training) and mitigations (abstraction layers, coding standards, ADRs). I avoid absolutes: Next fits when routing + rendering + deployment integration reduce total cost versus bolting libraries onto React alone.
// app/dashboard/layout.tsx
export default function DashboardLayout({ children }: { children: React.ReactNode }) {
return (
<div className="flex">
<aside>Nav</aside>
<section>{children}</section>
</div>
);
}
E086 — Drill 86: Multiple children slots in parallel routes layout.
Scenario: Multiple children slots in parallel routes layout. (variation 86: assume App Router, TypeScript, and a product team shipping weekly.)
Prompt: What decision do you make, what do you document, and what metric or artifact proves the outcome for case #86?
Model answer: I restate constraints (team size, SEO needs, deploy target, latency budget). I pick the smallest reversible step—often a spike branch or preview deployment—and define one success signal (e.g. p75 LCP, build time, DX survey). For drill #86, I call out risks (lock-in, complexity, training) and mitigations (abstraction layers, coding standards, ADRs). I avoid absolutes: Next fits when routing + rendering + deployment integration reduce total cost versus bolting libraries onto React alone.
// app/dashboard/layout.tsx
export default function DashboardLayout({ children }: { children: React.ReactNode }) {
return (
<div className="flex">
<aside>Nav</aside>
<section>{children}</section>
</div>
);
}
E087 — Drill 87: Font optimization via next/font in root layout.
Scenario: Font optimization via next/font in root layout. (variation 87: assume App Router, TypeScript, and a product team shipping weekly.)
Prompt: What decision do you make, what do you document, and what metric or artifact proves the outcome for case #87?
Model answer: I restate constraints (team size, SEO needs, deploy target, latency budget). I pick the smallest reversible step—often a spike branch or preview deployment—and define one success signal (e.g. p75 LCP, build time, DX survey). For drill #87, I call out risks (lock-in, complexity, training) and mitigations (abstraction layers, coding standards, ADRs). I avoid absolutes: Next fits when routing + rendering + deployment integration reduce total cost versus bolting libraries onto React alone.
// app/dashboard/layout.tsx
export default function DashboardLayout({ children }: { children: React.ReactNode }) {
return (
<div className="flex">
<aside>Nav</aside>
<section>{children}</section>
</div>
);
}
E088 — Drill 88: Metadata API in layout vs page precedence.
Scenario: Metadata API in layout vs page precedence. (variation 88: assume App Router, TypeScript, and a product team shipping weekly.)
Prompt: What decision do you make, what do you document, and what metric or artifact proves the outcome for case #88?
Model answer: I restate constraints (team size, SEO needs, deploy target, latency budget). I pick the smallest reversible step—often a spike branch or preview deployment—and define one success signal (e.g. p75 LCP, build time, DX survey). For drill #88, I call out risks (lock-in, complexity, training) and mitigations (abstraction layers, coding standards, ADRs). I avoid absolutes: Next fits when routing + rendering + deployment integration reduce total cost versus bolting libraries onto React alone.
// app/dashboard/layout.tsx
export default function DashboardLayout({ children }: { children: React.ReactNode }) {
return (
<div className="flex">
<aside>Nav</aside>
<section>{children}</section>
</div>
);
}
E089 — Drill 89: Avoiding duplicate headers across nested layouts.
Scenario: Avoiding duplicate headers across nested layouts. (variation 89: assume App Router, TypeScript, and a product team shipping weekly.)
Prompt: What decision do you make, what do you document, and what metric or artifact proves the outcome for case #89?
Model answer: I restate constraints (team size, SEO needs, deploy target, latency budget). I pick the smallest reversible step—often a spike branch or preview deployment—and define one success signal (e.g. p75 LCP, build time, DX survey). For drill #89, I call out risks (lock-in, complexity, training) and mitigations (abstraction layers, coding standards, ADRs). I avoid absolutes: Next fits when routing + rendering + deployment integration reduce total cost versus bolting libraries onto React alone.
// app/dashboard/layout.tsx
export default function DashboardLayout({ children }: { children: React.ReactNode }) {
return (
<div className="flex">
<aside>Nav</aside>
<section>{children}</section>
</div>
);
}
E090 — Drill 90: Migrating Pages Router _app global layout to App Router.
Scenario: Migrating Pages Router _app global layout to App Router. (variation 90: assume App Router, TypeScript, and a product team shipping weekly.)
Prompt: What decision do you make, what do you document, and what metric or artifact proves the outcome for case #90?
Model answer: I restate constraints (team size, SEO needs, deploy target, latency budget). I pick the smallest reversible step—often a spike branch or preview deployment—and define one success signal (e.g. p75 LCP, build time, DX survey). For drill #90, I call out risks (lock-in, complexity, training) and mitigations (abstraction layers, coding standards, ADRs). I avoid absolutes: Next fits when routing + rendering + deployment integration reduce total cost versus bolting libraries onto React alone.
// app/dashboard/layout.tsx
export default function DashboardLayout({ children }: { children: React.ReactNode }) {
return (
<div className="flex">
<aside>Nav</aside>
<section>{children}</section>
</div>
);
}
E091 — Drill 91: Root layout must include <html> and <body>.
Scenario: Root layout must include <html> and <body>. (variation 91: assume App Router, TypeScript, and a product team shipping weekly.)
Prompt: What decision do you make, what do you document, and what metric or artifact proves the outcome for case #91?
Model answer: I restate constraints (team size, SEO needs, deploy target, latency budget). I pick the smallest reversible step—often a spike branch or preview deployment—and define one success signal (e.g. p75 LCP, build time, DX survey). For drill #91, I call out risks (lock-in, complexity, training) and mitigations (abstraction layers, coding standards, ADRs). I avoid absolutes: Next fits when routing + rendering + deployment integration reduce total cost versus bolting libraries onto React alone.
// app/dashboard/layout.tsx
export default function DashboardLayout({ children }: { children: React.ReactNode }) {
return (
<div className="flex">
<aside>Nav</aside>
<section>{children}</section>
</div>
);
}
E092 — Drill 92: Nested layout adds sidebar only for /dashboard subtree.
Scenario: Nested layout adds sidebar only for /dashboard subtree. (variation 92: assume App Router, TypeScript, and a product team shipping weekly.)
Prompt: What decision do you make, what do you document, and what metric or artifact proves the outcome for case #92?
Model answer: I restate constraints (team size, SEO needs, deploy target, latency budget). I pick the smallest reversible step—often a spike branch or preview deployment—and define one success signal (e.g. p75 LCP, build time, DX survey). For drill #92, I call out risks (lock-in, complexity, training) and mitigations (abstraction layers, coding standards, ADRs). I avoid absolutes: Next fits when routing + rendering + deployment integration reduce total cost versus bolting libraries onto React alone.
// app/dashboard/layout.tsx
export default function DashboardLayout({ children }: { children: React.ReactNode }) {
return (
<div className="flex">
<aside>Nav</aside>
<section>{children}</section>
</div>
);
}
E093 — Drill 93: Layout vs template re-mount behavior difference.
Scenario: Layout vs template re-mount behavior difference. (variation 93: assume App Router, TypeScript, and a product team shipping weekly.)
Prompt: What decision do you make, what do you document, and what metric or artifact proves the outcome for case #93?
Model answer: I restate constraints (team size, SEO needs, deploy target, latency budget). I pick the smallest reversible step—often a spike branch or preview deployment—and define one success signal (e.g. p75 LCP, build time, DX survey). For drill #93, I call out risks (lock-in, complexity, training) and mitigations (abstraction layers, coding standards, ADRs). I avoid absolutes: Next fits when routing + rendering + deployment integration reduce total cost versus bolting libraries onto React alone.
// app/dashboard/layout.tsx
export default function DashboardLayout({ children }: { children: React.ReactNode }) {
return (
<div className="flex">
<aside>Nav</aside>
<section>{children}</section>
</div>
);
}
E094 — Drill 94: Loading.tsx skeleton hierarchy per segment.
Scenario: Loading.tsx skeleton hierarchy per segment. (variation 94: assume App Router, TypeScript, and a product team shipping weekly.)
Prompt: What decision do you make, what do you document, and what metric or artifact proves the outcome for case #94?
Model answer: I restate constraints (team size, SEO needs, deploy target, latency budget). I pick the smallest reversible step—often a spike branch or preview deployment—and define one success signal (e.g. p75 LCP, build time, DX survey). For drill #94, I call out risks (lock-in, complexity, training) and mitigations (abstraction layers, coding standards, ADRs). I avoid absolutes: Next fits when routing + rendering + deployment integration reduce total cost versus bolting libraries onto React alone.
// app/dashboard/layout.tsx
export default function DashboardLayout({ children }: { children: React.ReactNode }) {
return (
<div className="flex">
<aside>Nav</aside>
<section>{children}</section>
</div>
);
}
E095 — Drill 95: Error.tsx boundary scope for segment failures.
Scenario: Error.tsx boundary scope for segment failures. (variation 95: assume App Router, TypeScript, and a product team shipping weekly.)
Prompt: What decision do you make, what do you document, and what metric or artifact proves the outcome for case #95?
Model answer: I restate constraints (team size, SEO needs, deploy target, latency budget). I pick the smallest reversible step—often a spike branch or preview deployment—and define one success signal (e.g. p75 LCP, build time, DX survey). For drill #95, I call out risks (lock-in, complexity, training) and mitigations (abstraction layers, coding standards, ADRs). I avoid absolutes: Next fits when routing + rendering + deployment integration reduce total cost versus bolting libraries onto React alone.
// app/dashboard/layout.tsx
export default function DashboardLayout({ children }: { children: React.ReactNode }) {
return (
<div className="flex">
<aside>Nav</aside>
<section>{children}</section>
</div>
);
}
E096 — Drill 96: Multiple children slots in parallel routes layout.
Scenario: Multiple children slots in parallel routes layout. (variation 96: assume App Router, TypeScript, and a product team shipping weekly.)
Prompt: What decision do you make, what do you document, and what metric or artifact proves the outcome for case #96?
Model answer: I restate constraints (team size, SEO needs, deploy target, latency budget). I pick the smallest reversible step—often a spike branch or preview deployment—and define one success signal (e.g. p75 LCP, build time, DX survey). For drill #96, I call out risks (lock-in, complexity, training) and mitigations (abstraction layers, coding standards, ADRs). I avoid absolutes: Next fits when routing + rendering + deployment integration reduce total cost versus bolting libraries onto React alone.
// app/dashboard/layout.tsx
export default function DashboardLayout({ children }: { children: React.ReactNode }) {
return (
<div className="flex">
<aside>Nav</aside>
<section>{children}</section>
</div>
);
}
E097 — Drill 97: Font optimization via next/font in root layout.
Scenario: Font optimization via next/font in root layout. (variation 97: assume App Router, TypeScript, and a product team shipping weekly.)
Prompt: What decision do you make, what do you document, and what metric or artifact proves the outcome for case #97?
Model answer: I restate constraints (team size, SEO needs, deploy target, latency budget). I pick the smallest reversible step—often a spike branch or preview deployment—and define one success signal (e.g. p75 LCP, build time, DX survey). For drill #97, I call out risks (lock-in, complexity, training) and mitigations (abstraction layers, coding standards, ADRs). I avoid absolutes: Next fits when routing + rendering + deployment integration reduce total cost versus bolting libraries onto React alone.
// app/dashboard/layout.tsx
export default function DashboardLayout({ children }: { children: React.ReactNode }) {
return (
<div className="flex">
<aside>Nav</aside>
<section>{children}</section>
</div>
);
}
E098 — Drill 98: Metadata API in layout vs page precedence.
Scenario: Metadata API in layout vs page precedence. (variation 98: assume App Router, TypeScript, and a product team shipping weekly.)
Prompt: What decision do you make, what do you document, and what metric or artifact proves the outcome for case #98?
Model answer: I restate constraints (team size, SEO needs, deploy target, latency budget). I pick the smallest reversible step—often a spike branch or preview deployment—and define one success signal (e.g. p75 LCP, build time, DX survey). For drill #98, I call out risks (lock-in, complexity, training) and mitigations (abstraction layers, coding standards, ADRs). I avoid absolutes: Next fits when routing + rendering + deployment integration reduce total cost versus bolting libraries onto React alone.
// app/dashboard/layout.tsx
export default function DashboardLayout({ children }: { children: React.ReactNode }) {
return (
<div className="flex">
<aside>Nav</aside>
<section>{children}</section>
</div>
);
}
E099 — Drill 99: Avoiding duplicate headers across nested layouts.
Scenario: Avoiding duplicate headers across nested layouts. (variation 99: assume App Router, TypeScript, and a product team shipping weekly.)
Prompt: What decision do you make, what do you document, and what metric or artifact proves the outcome for case #99?
Model answer: I restate constraints (team size, SEO needs, deploy target, latency budget). I pick the smallest reversible step—often a spike branch or preview deployment—and define one success signal (e.g. p75 LCP, build time, DX survey). For drill #99, I call out risks (lock-in, complexity, training) and mitigations (abstraction layers, coding standards, ADRs). I avoid absolutes: Next fits when routing + rendering + deployment integration reduce total cost versus bolting libraries onto React alone.
// app/dashboard/layout.tsx
export default function DashboardLayout({ children }: { children: React.ReactNode }) {
return (
<div className="flex">
<aside>Nav</aside>
<section>{children}</section>
</div>
);
}
E100 — Drill 100: Migrating Pages Router _app global layout to App Router.
Scenario: Migrating Pages Router _app global layout to App Router. (variation 100: assume App Router, TypeScript, and a product team shipping weekly.)
Prompt: What decision do you make, what do you document, and what metric or artifact proves the outcome for case #100?
Model answer: I restate constraints (team size, SEO needs, deploy target, latency budget). I pick the smallest reversible step—often a spike branch or preview deployment—and define one success signal (e.g. p75 LCP, build time, DX survey). For drill #100, I call out risks (lock-in, complexity, training) and mitigations (abstraction layers, coding standards, ADRs). I avoid absolutes: Next fits when routing + rendering + deployment integration reduce total cost versus bolting libraries onto React alone.
// app/dashboard/layout.tsx
export default function DashboardLayout({ children }: { children: React.ReactNode }) {
return (
<div className="flex">
<aside>Nav</aside>
<section>{children}</section>
</div>
);
}
E101 — Drill 101: Root layout must include <html> and <body>.
Scenario: Root layout must include <html> and <body>. (variation 101: assume App Router, TypeScript, and a product team shipping weekly.)
Prompt: What decision do you make, what do you document, and what metric or artifact proves the outcome for case #101?
Model answer: I restate constraints (team size, SEO needs, deploy target, latency budget). I pick the smallest reversible step—often a spike branch or preview deployment—and define one success signal (e.g. p75 LCP, build time, DX survey). For drill #101, I call out risks (lock-in, complexity, training) and mitigations (abstraction layers, coding standards, ADRs). I avoid absolutes: Next fits when routing + rendering + deployment integration reduce total cost versus bolting libraries onto React alone.
// app/dashboard/layout.tsx
export default function DashboardLayout({ children }: { children: React.ReactNode }) {
return (
<div className="flex">
<aside>Nav</aside>
<section>{children}</section>
</div>
);
}
E102 — Drill 102: Nested layout adds sidebar only for /dashboard subtree.
Scenario: Nested layout adds sidebar only for /dashboard subtree. (variation 102: assume App Router, TypeScript, and a product team shipping weekly.)
Prompt: What decision do you make, what do you document, and what metric or artifact proves the outcome for case #102?
Model answer: I restate constraints (team size, SEO needs, deploy target, latency budget). I pick the smallest reversible step—often a spike branch or preview deployment—and define one success signal (e.g. p75 LCP, build time, DX survey). For drill #102, I call out risks (lock-in, complexity, training) and mitigations (abstraction layers, coding standards, ADRs). I avoid absolutes: Next fits when routing + rendering + deployment integration reduce total cost versus bolting libraries onto React alone.
// app/dashboard/layout.tsx
export default function DashboardLayout({ children }: { children: React.ReactNode }) {
return (
<div className="flex">
<aside>Nav</aside>
<section>{children}</section>
</div>
);
}
E103 — Drill 103: Layout vs template re-mount behavior difference.
Scenario: Layout vs template re-mount behavior difference. (variation 103: assume App Router, TypeScript, and a product team shipping weekly.)
Prompt: What decision do you make, what do you document, and what metric or artifact proves the outcome for case #103?
Model answer: I restate constraints (team size, SEO needs, deploy target, latency budget). I pick the smallest reversible step—often a spike branch or preview deployment—and define one success signal (e.g. p75 LCP, build time, DX survey). For drill #103, I call out risks (lock-in, complexity, training) and mitigations (abstraction layers, coding standards, ADRs). I avoid absolutes: Next fits when routing + rendering + deployment integration reduce total cost versus bolting libraries onto React alone.
// app/dashboard/layout.tsx
export default function DashboardLayout({ children }: { children: React.ReactNode }) {
return (
<div className="flex">
<aside>Nav</aside>
<section>{children}</section>
</div>
);
}
E104 — Drill 104: Loading.tsx skeleton hierarchy per segment.
Scenario: Loading.tsx skeleton hierarchy per segment. (variation 104: assume App Router, TypeScript, and a product team shipping weekly.)
Prompt: What decision do you make, what do you document, and what metric or artifact proves the outcome for case #104?
Model answer: I restate constraints (team size, SEO needs, deploy target, latency budget). I pick the smallest reversible step—often a spike branch or preview deployment—and define one success signal (e.g. p75 LCP, build time, DX survey). For drill #104, I call out risks (lock-in, complexity, training) and mitigations (abstraction layers, coding standards, ADRs). I avoid absolutes: Next fits when routing + rendering + deployment integration reduce total cost versus bolting libraries onto React alone.
// app/dashboard/layout.tsx
export default function DashboardLayout({ children }: { children: React.ReactNode }) {
return (
<div className="flex">
<aside>Nav</aside>
<section>{children}</section>
</div>
);
}
E105 — Drill 105: Error.tsx boundary scope for segment failures.
Scenario: Error.tsx boundary scope for segment failures. (variation 105: assume App Router, TypeScript, and a product team shipping weekly.)
Prompt: What decision do you make, what do you document, and what metric or artifact proves the outcome for case #105?
Model answer: I restate constraints (team size, SEO needs, deploy target, latency budget). I pick the smallest reversible step—often a spike branch or preview deployment—and define one success signal (e.g. p75 LCP, build time, DX survey). For drill #105, I call out risks (lock-in, complexity, training) and mitigations (abstraction layers, coding standards, ADRs). I avoid absolutes: Next fits when routing + rendering + deployment integration reduce total cost versus bolting libraries onto React alone.
// app/dashboard/layout.tsx
export default function DashboardLayout({ children }: { children: React.ReactNode }) {
return (
<div className="flex">
<aside>Nav</aside>
<section>{children}</section>
</div>
);
}