Single-SPA Best Practices

Best Practices Overview

At its core, best practices is about doing one thing well inside your single-spa project. Once you understand the pattern, you can apply it consistently across features and teams.

Good best practices pays off across the whole codebase: fewer surprises, easier testing, and smoother onboarding. The snippet below is a solid starting point.

import { registerApplication, start } from 'single-spa';

registerApplication({
  name: '@org/app',
  app: () => System.import('@org/app'),
  activeWhen: ['/app'],
});

start();

single-spa orchestrates multiple framework apps on one page through a root config.

Best Practices Example

registerApplication({
  name: '@org/app',
  app: () => System.import('@org/app'),
  activeWhen: ['/app'],
});
start();

• Start from a minimal Best Practices example and grow it only as needed.
• Keep configuration explicit so Best Practices behaves the same in every environment.
• Name things clearly so teammates understand your Best Practices at a glance.
• Add tests around Best Practices early to lock in expected behaviour.

Single-SPA Cheatsheet

Core single-spa APIs related to best practices.

How Best Practices Works in Single-SPA

Best Practices is part of how single-spa lets multiple applications — even in different frameworks — coexist on one page. A root config registers each app and controls when it is active.

single-spa orchestrates multiple framework apps on one page through a root config.

• A root config registers apps and calls start().
• Each app exports bootstrap, mount, and unmount lifecycles.
• activeWhen decides which routes each app owns.
• Import maps resolve each app's bundle at runtime.

Practical Guidance for Best Practices

For reliable micro frontends, best practices should isolate failures and keep shared state minimal. Let each team own its app end to end while agreeing on a few shared contracts.

Common Mistakes

• Skipping error handling and edge cases when wiring up best practices.
• Leaving best practices untested, so regressions slip into production.
• Over-engineering best practices before you actually need the extra flexibility.
• Ignoring documentation, which makes best practices hard for the next developer to change.

Key Takeaways

• Best Practices is a core part of working effectively with single-spa.
• Start small and keep best practices focused on a single responsibility.
• Apply consistent patterns so best practices scales across your project.
• Test and document best practices to keep it maintainable over time.