Unable to login

[robphoenix]

Running netlifyctl login fails with the following debug log:

DEBU[0000] PreRun                                        arguments=[] command=login
DEBU[0000] configure debug middleware                   
DEBU[0000] configure logging middleware                 
DEBU[0000] setup logger middleware: panic               
DEBU[0000] configure no auth middleware                 
DEBU[0000] setup credentials                             credentials=0x89a310
DEBU[0000] configure client middleware                  
DEBU[0000] setup API endpoint                            endpoint="https://api.netlify.com"
DEBU[0000] POST /api/v1/oauth/tickets?client_id=5edad8f69d47ae8923d0cf0b4ab95ba1415e67492b5af26ad97f4709160bb31b HTTP/1.1
Host: api.netlify.com
User-Agent: netlifyctl
Content-Length: 0
Accept: application/json
Content-Type: application/json
Accept-Encoding: gzip

DEBU[0000] HTTP/1.1 201 Created
Content-Length: 178
Age: 0
Alt-Svc: clear
Cache-Control: max-age=0, private, must-revalidate
Connection: keep-alive
Content-Type: application/json; charset=utf-8
Date: Fri, 04 May 2018 16:01:35 GMT
Etag: W/"094cb4cf62d9e842c3c8e9e359fcd2de"
Server: Netlify
Vary: Origin
Via: 1.1 google
Www-Authenticate: Bearer realm="user"
X-Frame-Options: ALLOWALL
X-Request-Id: a93c5a11-369d-417d-a711-21c7d562f0c1
X-Runtime: 0.039173

{"id":"8fde84822ac4013b3d31966b1eab897e","client_id":"5edad8f69d47ae8923d0cf0b4ab95ba1415e67492b5af26ad97f4709160bb31b","created_at":"2018-05-04T16:01:35.354Z","authorized":null}

ERRO[0001] command failed                                error="exit status 3"

Running netlifyctl version returns:

Version: unknown
Git SHA: unknown

though this appears to be expected

I've had no problem deploying with the JS cli tool.