Building Nx Monorepos with Remix

Modern web development increasingly demands scalable architectures that can handle multiple applications, shared libraries, and consistent tooling across teams. Nx monorepos combined with Remix offer a powerful solution for teams building complex web applications. This guide explores how to leverage Nx's monorepo capabilities with Remix's full-stack web framework to create maintainable, scalable, and performant applications.

By combining these technologies, teams can manage multiple Remix applications within a single repository while sharing code, enforcing architectural boundaries, and benefiting from Nx's powerful build system and caching mechanisms. This approach has been adopted by major technology companies including Google, Facebook, and Microsoft for their large-scale applications.

What is a Monorepo?

A monorepo is a single repository that contains multiple distinct projects with well-defined relationships. Rather than maintaining separate repositories for each application or library, a monorepo consolidates all code into one location while maintaining clear boundaries between projects.

The monorepo approach has gained significant traction in recent years, with major technology companies like Google, Facebook, and Microsoft adopting this pattern for their large-scale applications. Nx, developed by Nrwl, provides the tooling necessary to implement and manage monorepos effectively in the JavaScript and TypeScript ecosystem.

Remix is a full-stack web framework built on top of the Web Fetch API, offering server-side rendering, nested routes, and a modern approach to web development. By combining Remix with Nx, teams can manage multiple Remix applications within a single repository while sharing code, enforcing architectural boundaries, and benefiting from Nx's powerful build system and caching mechanisms.

Setting Up Nx with Remix

The process begins with creating a new Nx workspace that will serve as the foundation for your monorepo. Nx provides a command-line tool that streamlines workspace creation and plugin installation. For teams starting fresh, the create-nx-workspace command generates a configured workspace with sensible defaults.

For existing projects, Nx can be added incrementally, allowing teams to transition to a monorepo structure without requiring a complete rewrite. This gradual adoption path is particularly valuable for large teams with established codebases who want to realize the benefits of monorepo organization without disrupting ongoing development.

Once the workspace is created, the Remix plugin must be installed to enable Remix-specific functionality. The Nx Remix plugin provides generators for creating new Remix applications, libraries, and components, as well as executors for building, testing, and linting Remix projects within the monorepo context.

Project Structure and Organization

Application Organization

Each Remix application within the monorepo follows a consistent internal structure that aligns with Remix's conventions while benefiting from Nx's project isolation. Routes are organized within the app directory, leveraging Remix's file-based routing system. Components specific to the application reside alongside the routes that use them, while shared components are imported from dedicated library projects.

The application-level configuration, including environment-specific settings and Remix configuration, remains within the application directory. This encapsulation ensures that application-specific concerns stay isolated while shared configuration can be maintained in library code.

Nx's project inference capabilities mean that configuration files within each application directory are automatically recognized and managed. The nx.json file at the workspace root defines global Nx configuration, while project-specific configuration can be specified in project.json files within each application directory.

Library Organization

Libraries in an Nx monorepo serve as the building blocks that applications assemble into complete solutions. A common approach organizes libraries by domain or feature area: UI libraries contain design system components, feature libraries encapsulate business logic, utility libraries provide general-purpose functions, and API client libraries abstract network communication.

Nx's tagging system enables fine-grained control over library usage. Libraries can be tagged with scope indicators that communicate their intended consumers. For example, a library tagged as scope:shared might be accessible to all projects, while a library tagged as scope:admin might only be available to administrative applications.

Sharing Code Between Applications

Component Sharing Strategies

The primary motivation for extracting shared code into libraries is eliminating duplication while maintaining consistency. UI components represent the most common candidate for sharing since they typically implement design system elements that should appear uniform across all applications. When implementing a comprehensive design system, organizations can maintain brand consistency while reducing development overhead across all applications.

When sharing components, consider the trade-offs between flexibility and consistency. Highly configurable components that adapt to different contexts reduce duplication but introduce complexity. Conversely, very specific components ensure consistency but may require more variants to address different use cases.

Remix-specific patterns like nested layouts, loaders, and actions can also be shared through library code. Common page layouts, authentication flows, and error handling patterns become reusable when extracted into shared libraries. This approach ensures that all applications implement these patterns consistently and benefit from improvements made to the shared implementation.

Type and Schema Sharing

TypeScript types and data schemas represent another valuable category for sharing. Shared type definitions ensure that data structures are consistent across applications, which becomes particularly important when multiple applications work with the same backend services or databases. When these definitions change, all consuming applications receive type-checking errors that prompt necessary updates, preventing runtime errors.

Build Optimization and Caching

Nx's Computation Cache

Nx implements a sophisticated caching system that dramatically reduces build times by storing the results of previous operations. When a build or test command runs, Nx captures the outputs and associates them with a hash derived from the inputs. Subsequent operations with identical inputs retrieve cached results instead of recomputing.

For Remix applications, this caching extends to all aspects of the build process including TypeScript compilation, bundling, and asset processing. The cache persists across machines when using Nx Cloud, enabling distributed teams and CI systems to share cached results and avoid redundant work. This optimization directly impacts search engine rankings, as faster build times enable more frequent deployments and quicker iteration on performance improvements.

Affected Project Detection

The affected command identifies which projects have changed based on a comparison against a baseline, typically the main branch. This capability enables efficient CI pipelines that only build and test projects impacted by the current change rather than rebuilding the entire monorepo.

For Remix applications, affected detection considers route changes, component modifications, and library updates. When a shared library changes, all applications that depend on that library are flagged as affected. When application-specific code changes, only that application and its dependencies require rebuilding. This optimization becomes increasingly valuable as the monorepo grows.

Deployment Strategies

Independent Application Deployment

Each Remix application in the monorepo can be deployed independently, maintaining separate release cycles and deployment pipelines. This independence allows teams to move at their own pace while still benefiting from shared infrastructure and tooling. For organizations looking to automate their deployment workflows, Nx's affected-based deployment strategies provide a foundation for continuous delivery at scale.

Deployment configurations typically reside within each application directory, specifying build targets, environment variables, and deployment commands. Nx executors wrap deployment tools and provide consistent interfaces across all applications while respecting the specific requirements of each project's deployment target.

CI pipelines integrate with Nx to enable affected-based deployment strategies. When changes are committed, the pipeline identifies affected applications and deploys only those projects. This approach reduces deployment time and risk by avoiding unnecessary deployments of unchanged applications.

Coordinated Releases

Some scenarios require coordinating releases across multiple applications. Nx supports this pattern through release planning and versioning capabilities that span the entire monorepo. When a shared library version changes, applications that depend on it can be updated simultaneously. Nx's release tooling helps coordinate these updates by identifying affected projects and generating the necessary version bumps and changelog entries.

Best Practices and Patterns

Establishing Clear Boundaries

Successful monorepos require clear architectural boundaries that prevent inappropriate dependencies and maintain project isolation. Nx's lint rules and module boundary enforcement provide technical enforcement of these boundaries, but organizational culture must support the intended structure.

Document the intended architecture and communicate it effectively to all team members. New projects should follow established patterns, and refactoring efforts should maintain or improve architectural clarity. Regular architecture reviews help catch boundary violations before they accumulate into technical debt.

Incremental Adoption

For teams transitioning from multi-repo to monorepo structures, incremental adoption minimizes risk. Start by migrating the most related projects first, establishing patterns and tooling before expanding to additional applications. Nx supports this approach by allowing projects to be added to an existing workspace over time.

Legacy applications can run alongside new monorepo projects during transition periods. This parallel operation provides stability while teams learn new workflows and establish patterns that will govern the monorepo's ongoing development. As confidence grows, additional projects can be migrated into the monorepo structure.

Sources

1. Nx: Overview of the Nx Remix Plugin
2. LogRocket: Building Nx monorepos with Remix
3. Nx: Monorepos