Ember app shows blank screen - may be dependency issue

When I start the ember server, I get the following two errors with a blank screen:

Uncaught Error: an unsupported module was defined, expected define(name, deps, module) instead got: 1 arguments to define`

Uncaught Error: Could not find module ember-resolver imported from webapp/resolver

package.json:
"devDependencies": { "babel-eslint": "^6.0.0-beta.6", "broccoli-asset-rev": "^2.4.2", "broccoli-sass": "^0.7.0", "ember-ajax": "0.7.1", "ember-buffered-proxy": "0.6.0", "ember-cli": "2.4.3", "ember-cli-app-version": "^1.0.0", "ember-cli-babel": "^5.1.6", "ember-cli-dependency-checker": "^1.2.0", "ember-cli-deploy": "0.6.1", "ember-cli-deploy-build": "0.1.1", "ember-cli-deploy-display-revisions": "0.2.1", "ember-cli-deploy-gzip": "0.2.3", "ember-cli-deploy-manifest": "0.1.1", "ember-cli-deploy-revision-data": "0.2.3", "ember-cli-deploy-s3": "0.3.0", "ember-cli-deploy-s3-index": "0.4.0", "ember-cli-eslint": "1.3.0", "ember-cli-htmlbars": "^1.0.3", "ember-cli-htmlbars-inline-precompile": "^0.3.1", "ember-cli-inject-live-reload": "^1.4.0", "ember-cli-notifications": "3.3.1", "ember-cli-qunit": "^1.4.0", "ember-cli-release": "0.2.8", "ember-cli-sri": "^2.1.0", "ember-cli-uglify": "^1.2.0", "ember-data": "^2.4.2", "ember-export-application-global": "^1.0.5", "ember-load-initializers": "^0.5.1", "ember-resolver": "^2.1.0", "ember-truth-helpers": "1.2.0", "eslint": "^2.9.0", "eslint-config-ember": "0.3.0", "loader.js": "^4.0.11" }

Already tried switching to different ember versions, 2.8.0, 2.4.3, 2.6.1.