Version Range Strategy

Version range strategy determines how design systems specify dependencies on other packages. The strategy affects how consumer projects resolve dependencies, receive updates, and handle conflicts. Choosing appropriate version ranges balances stability with receiving beneficial updates.

What Is Version Range Strategy

Version range strategy is the approach to specifying dependency versions in package.json. Rather than exact versions, ranges allow compatible versions to satisfy dependencies. Common range operators include caret (^), tilde (~), and comparison operators. The strategy defines which operator to use and when.

For design systems, version range strategy applies to both the packages the design system publishes (affecting consumers) and internal development dependencies. The strategy may differ between these contexts based on different goals.

How Version Range Strategy Works

Version range specification uses semver-based operators to define acceptable versions. Understanding these operators enables strategic choices.

Caret ranges (^) allow minor and patch updates. ^1.2.3 accepts versions from 1.2.3 up to (but not including) 2.0.0. This assumes semver compliance where minor versions add features without breaking compatibility.

Tilde ranges (~) allow only patch updates. ~1.2.3 accepts versions from 1.2.3 up to (but not including) 1.3.0. This is more conservative, only accepting bug fixes automatically.

Exact versions lock to specific releases. 1.2.3 accepts only that exact version. This maximizes reproducibility but prevents automatic updates.

Greater than or equal (>=) sets minimum versions. >=1.2.3 accepts any version from 1.2.3 onward, including major versions. This is very permissive and rarely appropriate except for peer dependencies.

Combined ranges express complex requirements. ^1.2.3 || ^2.0.0 accepts either version 1 or version 2. This supports multiple major versions simultaneously.

Key Considerations

• Consider semver compliance of depended-on packages
• Balance update receipt with stability needs
• Use lockfiles to ensure reproducible builds
• Differentiate strategy between dependencies and peerDependencies
• Document strategy for team consistency

Common Questions

What version range should design systems use for their dependencies?

The optimal range depends on the dependency type and trust in semver compliance. Different contexts warrant different approaches.

For well-maintained dependencies following semver, caret ranges work well. Receiving minor and patch updates provides security fixes and improvements. The risk of breaking changes in minor versions is low for semver-compliant packages.

For less predictable dependencies, tilde ranges provide safety. Only accepting patch updates limits exposure to potentially breaking changes. This conservative approach trades feature updates for stability.

For production dependencies affecting consumers, lean conservative. Consumer projects inherit these dependencies. Unexpected updates could break consumers. Careful range specification protects consumer experience.

For development dependencies not affecting consumers, broader ranges are acceptable. Build tools, linters, and testing frameworks updating do not affect published packages. More permissive ranges reduce maintenance overhead.

How do lockfiles interact with version ranges?

Lockfiles (package-lock.json, yarn.lock) record exact resolved versions despite range specifications. Understanding this interaction clarifies how ranges affect behavior.

Development uses locked versions. Running npm install with an existing lockfile installs the locked versions, not the latest within ranges. This ensures reproducibility.

CI/CD should respect lockfiles. Using npm ci instead of npm install installs exact locked versions, ensuring consistent builds.

Ranges affect updates. Running npm update resolves ranges to the latest matching versions, updating the lockfile. This is when ranges actually determine which versions are used.

Published packages include ranges, not locks. Consumers receive range specifications, not lockfile contents. Their own resolution process determines actual installed versions.

Summary

Version range strategy determines how dependencies are specified and resolved. Caret ranges allow minor updates while tilde ranges restrict to patches. Strategic range selection balances receiving beneficial updates with maintaining stability. Lockfiles provide reproducibility while ranges determine update scope.