Bower installation ignores devDependencies during standard fetch

Question

In Bower, the bower.json file supports both dependencies and devDependencies. While the --save and --save-dev flags populate these respective sections, the core installation logic does not differentiate between them during the fetch process.

Running a standard bower install command downloads all packages listed in both categories into the bower_components directory. There is no documented flag or configuration to exclude development dependencies when preparing a build for a production-like environment. This behavior contrasts with many other modern package managers where dev-only tools are omitted to minimize the runtime footprint.Is there a documented flag to skip the installation of devDependencies? If not, is the devDependencies field intended solely as metadata without functional impact on the install workflow?

Tasadduq Burney · Answer

Answer
Running bower install always pulls every dependency listed in bower.json, regardless of whether it appears under dependencies or devDependencies. The core Bower installer treats the two sections identically; there is no CLI option, configuration key, or environment variable that tells Bower to ignore devDependencies during a normal fetch.
Why the field matters
Although devDependencies is conceptually “development‑only”, it is not merely metadata. Packages declared there are physically installed into bower_components and become part of the repository’s source tree. The field is therefore a hint for build tools rather than a gatekeeper for the package manager itself.
Common work‑arounds

Use a build tool (Grunt, Gulp, Webpack) to copy only the runtime dependencies into the final distribution.
Maintain a separate bower.json for production that omits devDependencies and run bower install --save against it.
After a normal bower install, delete the dev packages manually or with a script.

Verification steps for your project

cat bower.json – confirm the devDependencies section.
bower install
ls bower_components | grep -E "(package1|package2)" – check that dev packages are present.
If you want to confirm the behavior is not version‑specific, run bower --version and compare with the documented 1.x behaviour.

What to ask next
Could you share the exact Bower version you’re using? While the behaviour is consistent across 1.x releases, early pre‑1.0 alphas may have differed slightly.
Diagram

ComponentAction
bower.jsonLists dependencies & devDependencies
bower installInstalls all listed packages
bower_componentsContains both runtime and dev packages

Bower installation ignores devDependencies during standard fetch

1 answer

Answer

Why the field matters

Common work‑arounds

Verification steps for your project

What to ask next

Diagram

Your perspective belongs here.

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Component	Action
bower.json	Lists dependencies & devDependencies
bower install	Installs all listed packages
bower_components	Contains both runtime and dev packages