tslint.json extends rule not being picked up

[mpace965]

Below is my tslint.json

{
    "extends": [
        "shared-tslint"
    ]
}

where shared-tslint is a package I have installed containting tslint settings to extend.

Expected behavior: I get linter errors in Atom from the rules in the specified package.
Actual behavior: The linter errors I get in Atom are different from those I get when I manually run tslint.