📎 Metalsmith plugin to concatenate files
JavaScript CSS


NPM version Linux build status Windows build status Code coverage GPA Dependencies status


A Metalsmith plugin to concatenate files.


$ npm install metalsmith-concat



  "plugins": {
    "metalsmith-concat": {
      "files": "styles/**/*.css",
      "output": "styles/app.css"


var MetalSmith = require('metalsmith');
var concat = require('metalsmith-concat');

    files: 'styles/**/*.css',
    output: 'styles/app.css'


Type: String / String[] Default: '**/*'

This defines which files are concatenated. This string will be interpreted as a minimatch pattern. An array of strings will be interpreted as minimatch patterns, in this case the order of the patterns matters (it will determine the order in which the files are concatenated).


Type: String

It represents the filepath where the concatenated content will be outputted. This option is mandatory.


Type: Boolean Default: false

By default metalsmith-concat return an error if the output file already exists. You can force an existing output file to be overwritten by setting this option to true.


Type: Boolean / String Default: true

Whether a trailing new line (\n) should be appended after each concatenated file. Unless you face a problem, you should keep this option on as removing it could cause invalid concatenated files (see this article). It is also possible to pass a string, in which case it will be used instead of \n.


Type: Boolean Default: false

Whether to keep the files which were concatenated. By default they are not kept and deleted from the build (thus only keeping the newly created file at options.output).


Type: String / String[] Default: []

The additional paths to search after the src directory given to Metalsmith. The paths are resolved relatively to the metalsmith root directory. Absolute paths can also been given. This feature is disabled by default. Example:

  files: [
    'react/dist/react.min.js', // will be resolved from the node_modules
    'index.js' // will be resolved from the directory given to Metalsmith
  searchPaths: [ 'node_modules' ]


  • 6.0.0

    • Expect and produce a Buffer for the contents key (breaking)
  • 5.0.2

    • Simplify the path given in the pattern
  • 5.0.1

    • Fix 100% code coverage on Node 4 (sandboxed-module -> proxyquire)
  • 5.0.0

    • Add the searchPaths option
    • Switch test suite to nyc + ava
  • 4.2.2

    • Lightweight npm-shrinkwrap
  • 4.2.1

    • Update license to public domain
  • 4.2.0

    • Require options.output to be a non-empty string
  • 4.1.1

    • Exclude test files from CodeClimate
  • 4.1.0

    • It is possible to override existing output file check by setting options.forceOutput to true (#19)
    • Handle metalsmith errors gracefully as described here
  • 4.0.1

    • Drop node 0.10 and 0.12 support as Metalsmith requires generators
  • 4.0.0

    • Update dependencies
    • Remove npm-shrinkwrap
    • Fix linting
    • Add node 4 and 5 to Travis/AppVeyor
  • 3.0.0

    • An array of minimatch patterns can now be passed as options.files (#6, #9)
    • File paths are normalized, hence making this plugin working on Windows (#8)
    • It is possible to pass a custom options.insertNewline character
  • 2.0.0

    • Add a newline at the end of each concatenated file by default (#4)
  • 1.0.1

    • Add the possibility to pass an array of files instead of a matching pattern (#2)
  • 1.0.0

    • Bump stable
  • 0.0.2

    • Fix an issue with file content
  • 0.0.1

    • Working plugin



To the extent possible under law, Aymeric Beaumet has waived all copyright and related or neighboring rights to this work.