Npm can't find `mkdirp`

Our builds started failing on CI all of a sudden with this error message. Previously passing builds are also failing with the same error.

Complete stacktrace here:

Module build failed: Error: Cannot find module 'mkdirp'
    at Function.Module._resolveFilename (module.js:470:15)
    at Function.Module._load (module.js:418:25)
    at Module.require (module.js:498:17)
    at require (internal/module.js:20:19)
    at Object.<anonymous> (/home/ubuntu/Border-Buddy/node_modules/eslint-loader/node_modules/loader-fs-cache/index.js:12:14)
    at Module._compile (module.js:571:32)
    at Module._extensions..js (module.js:580:10)
    at Object.require.extensions.(anonymous function) [as .js] (/home/ubuntu/Border-Buddy/node_modules/babel-register/lib/node.js:152:7)
    at Module.load (module.js:488:32)
    at tryModuleLoad (module.js:447:12)
    at Function.Module._load (module.js:439:3)
    at Module.require (module.js:498:17)
    at require (internal/module.js:20:19)
    at Object.<anonymous> (/home/ubuntu/Border-Buddy/node_modules/eslint-loader/index.js:6:19)
    at Module._compile (module.js:571:32)
    at Module._extensions..js (module.js:580:10)
    at Object.require.extensions.(anonymous function) [as .js] (/home/ubuntu/Border-Buddy/node_modules/babel-register/lib/node.js:152:7)
    at Module.load (module.js:488:32)
    at tryModuleLoad (module.js:447:12)
    at Function.Module._load (module.js:439:3)
    at Module.require (module.js:498:17)
    at require (internal/module.js:20:19)
    at loadLoader (/home/ubuntu/Border-Buddy/node_modules/webpack/node_modules/loader-runner/lib/loadLoader.js:13:17)
    at iteratePitchingLoaders (/home/ubuntu/Border-Buddy/node_modules/webpack/node_modules/loader-runner/lib/LoaderRunner.js:169:2)
    at iteratePitchingLoaders (/home/ubuntu/Border-Buddy/node_modules/webpack/node_modules/loader-runner/lib/LoaderRunner.js:165:10)
    at /home/ubuntu/Border-Buddy/node_modules/webpack/node_modules/loader-runner/lib/LoaderRunner.js:173:18
    at loadLoader (/home/ubuntu/Border-Buddy/node_modules/webpack/node_modules/loader-runner/lib/loadLoader.js:36:3)
    at iteratePitchingLoaders (/home/ubuntu/Border-Buddy/node_modules/webpack/node_modules/loader-runner/lib/LoaderRunner.js:169:2)
    at runLoaders (/home/ubuntu/Border-Buddy/node_modules/webpack/node_modules/loader-runner/lib/LoaderRunner.js:362:2)
    at NormalModule.doBuild (/home/ubuntu/Border-Buddy/node_modules/webpack/lib/NormalModule.js:179:3)
 @ multi ./client/index.js

This hit me on a project. I couldn’t find a sane fix but luckily we realized that we aren’t using sass anymore so we just removed it. :confused: