Missing gitlab-runner-helper

My shared runner (only one repo really using it) does the following when building:

Running with gitlab-ci-multi-runner dev (1.5.2)
Using Docker executor with image node:6 ...
Pulling docker image node:6 ...
Running on runner-bfd8632d-project-38-concurrent-0 via redacted-host...
Cloning repository...
Cloning into '/builds/redacted-namespace/redacted-repo'...
Checking out 934fb275 as master...
Missing /usr/bin/gitlab-runner-helper. Extracting cache is disabled.
$ id -u "ci" &>/dev/null || useradd "ci"
$ mkdir /home/ci && chown ci /home/ci
$ su "ci" -c "npm i --loglevel warn"
...installs NPM deps perfectly fine...
$ npm run-script build
...runs build perfectly fine...
Missing /usr/bin/gitlab-runner-helper. Creating cache is disabled.
Missing /usr/bin/gitlab-runner-helper. Uploading artifacts is disabled.
Build succeeded

Why is it missing /usr/bin/gitlab-runner-helper? Should I try removing the runners and gitlab-ci-multi-runner and setting up the runners from scratch?

Debian Jessie 8.5 x64