Also mentioned in pull request #2076 (for the 3.1 branch), this one is for the 3.2 branch.
Fixed issue #1859: ArgumentError for to_xs after instruct! is called
This pull request fails (merged 897e322 into e50abba).
This has been fixed with builder 3.0.1, run bundle update builder to get the new version with the proper fix. Closing here, thanks.
bundle update builder