When running gulp in spark cannot find acorn

I installed spark on Windows, but gulp will not run

gulp

[21:16:46] Using gulpfile ~\Documents\GitHub\champ\gulpfile.js [21:16:46] Starting 'all'... [21:16:46] Starting 'less'... [21:16:50] Finished 'less' after 3.55 s [21:16:50] Starting 'webpack'... { [Error: ./resources/assets/js/app.js Module build failed: Error: Cannot find module 'acorn/dist/acorn.js' at Function.Module._resolveFilename (module.js:325:15) at Function.Module._load (module.js:276:25) at Module.require (module.js:353:17) at require (internal/module.js:12:17) at __commonjs_global (C:\Users\user\Documents\GitHub\node_modules\buble\dist\buble.umd.js:2:83) at Object. (C:\Users\user\Documents\GitHub\node_modules\buble\dist\buble.umd.js:5:2) at Module._compile (module.js:409:26) at Object.Module._extensions..js (module.js:416:10) at Module.load (module.js:343:32) at Function.Module._load (module.js:300:12)] message: './resources/assets/js/app.js\nModule build failed: Error: Cannot find module 'acorn/dist/acorn.js'\n at Function.Module._resolveFilename (module.js:325:15)\n at Function.Module._load (module.js:276:25)\n at Module.require (module.js:353:17)\n at require (internal/module.js:12:17)\n at __commonjs_global (C:\Users\user\Documents\GitHub\node_modules\buble\dist\buble.umd.js:2:83)\n at Object. (C:\Users\user\Documents\GitHub\node_modules\buble\dist\buble.umd.js:5:2)\n at Module._compile (module.js:409:26)\n at Object.Module._extensions..js (module.js:416:10)\n at Module.load (module.js:343:32)\n at Function.Module._load (module.js:300:12)', showStack: false, showProperties: true, plugin: 'webpack-stream', __safety: { toString: [Function: bound ] } }

I've tried npm install acorn and npm install -g acorn with no success...

Any ideas?