Fix exponential backoff

[bgourlie]

Fixes #17

[process-bot]

Thanks for the pull request! Make sure it satisfies this checklist. My human colleagues will appreciate it!

Here is what to expect next, and if anyone wants to comment, keep these things in mind.

[drathier]

@bgourlie would you like to fix #26 in this PR as well?

[bgourlie]

If I had some confidence that the effort wouldn’t be in vein I’d consider it, but I’m not sure this will ever be merged.