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You've carefully architected your Next.js application using Parallel Routes for dynamic dashboard layouts and Route Groups for clean code organization. Everything works flawlessly in development—slots render correctly, navigation is smooth, and your template.tsx files provide the exact behavior you need. Then you run next build followed by next start, and you're greeted with a white screen or a 404 error.
If this scenario sounds painfully familiar, you've encountered a known issue where Parallel Routes inside Route Groups fail to work in production when Partial Prerendering (PPR) is enabled. This bug affects developers who combine these three powerful Next.js features, and it can be particularly frustrating because development mode gives no indication that anything is wrong.
In this comprehensive guide, we'll dissect the root cause of this issue, understand why it specifically affects production builds, and walk through the definitive fix that the Next.js team implemented in version 14.2.4 and later.
The issue manifests in a very specific pattern that makes it challenging to debug. When you combine:
@folder convention for slots)(folderName) convention for organization)The application works perfectly during development (next dev), but after building (next build) and starting the production server (next start), you encounter one of these symptoms:
Here's a typical folder structure that triggers this issue when Parallel Routes inside Route Groups are used with PPR enabled:
app/
├── (dashboard)/
│ ├── layout.tsx
│ ├── template.tsx # This file is key to the conflict
│ ├── @analytics/
│ │ ├── page.tsx
│ │ └── default.tsx
│ ├── @team/
│ │ ├── page.tsx
│ │ └── default.tsx
│ └── page.tsx
└── layout.tsx
And here's the typical configuration that enables PPR:
// next.config.ts
import type { NextConfig } from "next";
const nextConfig: NextConfig = {
experimental: {
ppr: true, // Enabling PPR triggers the issue
},
};
export default nextConfig;With this setup, navigating to the dashboard in development mode correctly renders both the @analytics and @team parallel slots. However, the same navigation in production results in a white screen or 404 error.
This issue was extensively documented in GitHub Issue #61352, where multiple developers reported identical symptoms. The issue was labeled with "bug", "area: experimental", "Parallel & Intercepting Routes", and "Partial Prerendering (PPR)", confirming its specific nature.
Understanding why this bug occurs requires knowledge of how three Next.js features interact during the build process.
Parallel Routes use named slots defined with the @folder convention. These slots are passed as props to the parent layout:
// app/(dashboard)/layout.tsx
export default function DashboardLayout({
children,
analytics,
team,
}: {
children: React.ReactNode;
analytics: React.ReactNode;
team: React.ReactNode;
}) {
return (
<div className="dashboard-grid">
<main>{children}</main>
<aside>{analytics}</aside>
<section>{team}</section
Slots are not route segments—they don't affect the URL structure. The @analytics slot doesn't add /analytics to the URL path; instead, it provides content that renders alongside other slots at the same URL.
Route Groups use the (folderName) convention to organize routes without affecting the URL path. A folder named (dashboard) groups dashboard-related routes together but is excluded from the URL structure.
The template.tsx file is similar to layout.tsx but with a crucial difference: templates are given a unique key based on the route, causing children Client Components to reset their state on navigation. The template is rendered between a layout and its children:
<Layout>
{/* Note that the template is given a unique key */}
<Template key={routeParam}>{children}</Template>
</Layout>During the PPR build phase, Next.js precomputes static HTML shells for routes. When Parallel Routes exist inside Route Groups, and those route groups contain a template.tsx file, the build process incorrectly resolves the template's relationship to the parallel slots.
The conflict arises because:
When these three interact, the PPR build phase generates incorrect static output. The template keys don't properly propagate to parallel route slots within route groups, causing the production build to fail to match routes that work in development mode.
In development mode, routes are evaluated dynamically, and the template-slot relationship resolves correctly on each request. But the static analysis performed during next build with PPR enabled fails to establish these relationships properly within route groups, leading to the white screen or 404 errors when using Parallel Routes inside Route Groups with PPR.
The Next.js team addressed this issue with internal fixes to how route group templates are processed during the PPR build phase. The fix was included in Next.js version 14.2.4 and later.
First, verify your current Next.js version:
# Check package.json
cat package.json | grep '"next"'
# Or use npm
npm list nextUpdate to version 14.2.4 or later:
# Using npm
npm install next@latest
# Using yarn
yarn add next@latest
# Using pnpm
pnpm add next@latest
# Or specify a minimum version
npm install [email protected]After updating, rebuild and test your application:
# Clean the build cache
rm -rf .next
# Rebuild
npm run build
# Start production server
npm run startNavigate to the routes that previously failed. With the updated version, Parallel Routes inside Route Groups should now work correctly with PPR enabled.
If you cannot immediately update Next.js, you can temporarily restructure your application to avoid the conflict. Move parallel routes outside of route groups:
Before (problematic structure):
app/
├── (dashboard)/
│ ├── @analytics/
│ │ └── page.tsx
│ └── @team/
│ └── page.tsx
After (workaround structure):
app/
├── dashboard/
│ ├── @analytics/
│ │ └── page.tsx
│ └── @team/
│ └── page.tsx
This removes the route group but adds "dashboard" to your URL path (/dashboard instead of /). It's not ideal, but it resolves the immediate issue while you plan the proper upgrade.
While the specific bug with Parallel Routes inside Route Groups and PPR has been fixed in Next.js 14.2.4+, there are broader lessons to apply when using experimental Next.js features.
Experimental features like PPR (now evolved into Cache Components in Next.js 16+) undergo rapid iteration. When combining multiple advanced routing features, minimize nesting complexity:
// Prefer flatter structures with experimental features
app/
├── dashboard/
│ ├── @slot1/
│ └── @slot2/
├── marketing/
│ └── page.tsxInstead of:
// Avoid deep nesting with experimental features
app/
├── (auth)/
│ ├── (dashboard)/
│ │ ├── (admin)/
│ │ │ ├── @slot1/
│ │ │ └── @slot2/The discrepancy between development and production behavior is a common pitfall. Integrate production build testing into your development workflow:
# Add to package.json scripts
{
"scripts": {
"build:test": "next build && next start",
"ci:validate": "next build && npm run test:e2e"
}
}When using template.tsx with parallel routes, keep the template logic minimal:
// app/dashboard/template.tsx
// Keep template simple to avoid routing conflicts
export default function DashboardTemplate({
children,
}: {
children: React.ReactNode;
}) {
return <div className="dashboard-wrapper">{children}</div>;
}Avoid complex conditional rendering or heavy computations in templates when using them with parallel routes and experimental features.
PPR has evolved significantly across Next.js versions. In Next.js 16, it's been renamed to Cache Components with a new cacheComponents configuration option. Stay current with the Next.js release notes to understand breaking changes and fixes.
Always include default.tsx files in your parallel route slots. These provide fallback content when a slot doesn't match the current route:
// app/dashboard/@analytics/default.tsx
export default function AnalyticsDefault() {
return null; // Or loading state, skeleton, etc.
}This prevents rendering issues when navigating between routes where not all slots have matching content.
Parallel Routes inside Route Groups fail in production (not development) when PPR is enabled due to conflicts between route group organization and template.tsx logic during the build phase.
The root cause is the PPR build phase incorrectly resolving template relationships to parallel route slots within route groups, generating invalid static output.
Upgrading to Next.js 14.2.4 or later resolves the issue, as the Next.js team implemented internal fixes for route group template processing.
Always test production builds when using experimental features—development mode may not reveal issues that only appear after next build.
Minimize nesting complexity when combining parallel routes, route groups, and experimental features to reduce the risk of encountering edge-case bugs.
Check your Next.js version and update to 14.2.4+ if you're experiencing this issue with Parallel Routes inside Route Groups and PPR.
Review your route structure for unnecessary nesting of parallel routes within multiple route groups.
Implement production build testing in your CI/CD pipeline to catch development-production discrepancies early.
Consider migrating to Cache Components (Next.js 16+) if you're starting a new project—it represents the stable evolution of PPR with improved APIs.
Monitor GitHub Issue #61352 for any additional context or related issues reported by the community.
By understanding the interaction between these powerful Next.js features and keeping your framework version current, you can confidently use Parallel Routes, Route Groups, and Partial Prerendering together in production applications.