This is not currently causing build failures because things are working fine on npm 3 (node 6), and the projects already switched to npm 6 (node 10) are only those not affected by this bug.
But, in trying out node10 on a number of projects, some of them consistently fail in this way.
## Repos on which Node 10 / npm 6 fails (but Node 6 / npm 3 passes)
* node-rdkafka-statsd ([change](https://gerrit.wikimedia.org/r/#/c/node-rdkafka-statsd/+/324277/); [build](https://integration.wikimedia.org/ci/job/generic-node10-docker/34/console))
* labs/tools/heritage ([change](https://gerrit.wikimedia.org/r/#/c/labs/tools/heritage/+/487801/); [build](https://integration.wikimedia.org/ci/job/generic-node10-docker/31/console))
* pywikibot/i18n ([change](https://gerrit.wikimedia.org/r/#/c/pywikibot/i18n/+/487578/))
* wikibase/javascript-api ([change](https://gerrit.wikimedia.org/r/#/c/wikibase/javascript-api/+/473168/))
* performance/fresnel (when a node_modules dir exists).
* wikipeg ([change](https://gerrit.wikimedia.org/r/#/c/wikipeg/+/495594/), [build](https://integration.wikimedia.org/ci/job/generic-node10-docker/124/console))
* mediawiki/extensions/Flow
* mediawiki/extensions/TemplateData
* mediawiki/extensions/Wikibase
```counterexample
+ rm -rf node_modules
+ npm install --no-progress
...
npm ERR! code Z_DATA_ERROR
npm ERR! errno -3
npm ERR! invalid distance too far back
```