TypeError: undefined is not a function when building

[fbjerggaard]

I am getting the above error when running either npm run build or npm run watch

This is the output of npm run build:

> vanilla-bootstrap@ build D:\code\bootstrap
> gulp

[20:55:05] Using gulpfile D:\code\bootstrap\gulpfile.js
[20:55:05] Starting 'styles'...
[20:55:06] 'styles' errored after 799 ms
[20:55:06] TypeError: undefined is not a function
    at Gulp.<anonymous> (D:\code\bootstrap\gulpfile.js:23:18)
    at module.exports (D:\code\bootstrap\node_modules\gulp\node_modules\orchestrator\lib\runTask.js:34:7)
    at Gulp.Orchestrator._runTask (D:\code\bootstrap\node_modules\gulp\node_modules\orchestrator\index.js:273:3)
    at Gulp.Orchestrator._runStep (D:\code\bootstrap\node_modules\gulp\node_modules\orchestrator\index.js:214:10)
    at Gulp.Orchestrator.start (D:\code\bootstrap\node_modules\gulp\node_modules\orchestrator\index.js:134:8)
    at D:\code\bootstrap\node_modules\gulp\bin\gulp.js:129:20
at process._tickCallback (node.js:355:11)
    at Function.Module.runMain (module.js:503:11)
    at startup (node.js:129:16)
    at node.js:814:3

    npm ERR! Windows_NT 6.3.9600
    npm ERR! argv "C:\\Program Files\\nodejs\\\\node.exe" "C:\\Program         Files\\nodejs\\node_modules\\npm\\bin\\npm-cli.js" "run" "build"
    npm ERR! node v0.12.7
    npm ERR! npm  v2.11.3
    npm ERR! code ELIFECYCLE
    npm ERR! vanilla-bootstrap@ build: `gulp`
    npm ERR! Exit status 1
    npm ERR!
    npm ERR! Failed at the vanilla-bootstrap@ build script 'gulp'.
    npm ERR! This is most likely a problem with the vanilla-bootstrap package,
    npm ERR! not with npm itself.
    npm ERR! Tell the author that this fails on your system:
    npm ERR!     gulp
    npm ERR! You can get their info via:
    npm ERR!     npm owner ls vanilla-bootstrap
    npm ERR! There is likely additional logging output above.

[fbjerggaard]

This happens on both Windows and Linux node.js 0.12.7 from a fresh install.

[fbjerggaard]

@kasperisager - Building works fine, the watch command however still gives me the same error.