When I use the Fastlane match tool on CircleCI I get an IO error from Ruby. This works perfectly on my machine, and I’m using the same versions of Ruby and all gems.
/dev/pts/6 is a pseudo-terminal. I suspect that match/git might be having a problem running without a real terminal.
Looks like this is being fixed in match: https://github.com/fastlane/match/issues/72