There's an old closed issue #148 where someone reported problems installing dugite behind a proxy. The recommended solution was to set HTTP_PROXY/HTTPS_PROXY which is also documented in the environment variable docs. It seems, however, that when dugite migrated away from requests, those environment variables stopped having any effect.

Now that dugite is using the raw https module, it looks like the easiest solution might be to add global-agent as a dependency and use it inside download-git.js. Here's how @electron/get uses global-agent, for example.

If that solution makes sense (or if you can suggest another solution you'd prefer), I'd be happy to submit a PR.