Development record

The implement receipt Long help at internal/surface/cli/build.go:1112-1114 calls the implementer receipt's resolves list optional. On an issue run (build of an issue, or a drain lane) the receipt is refused unless resolves names the lane's issue (internal/core/implement/loop/receipt.go:405-407, added in 2cec1e367), and an implementer may hand the lane back with a handback object instead of commits, which ends the lane (receipt.go:69-73,398-400). The help mentions neither; it renders at docs/reference/cli/commands.md:2659-2661.