bindata.go must be generated with https://github.com/jteeuwen/go-bindata.

From the gotests root run $ go generate ./....

Or run $ go-bindata -pkg=bindata -o "internal/render/bindata/bindata.go" internal/render/templates/.

During development run $ go-bindata -pkg=bindata -o "internal/render/bindata/bindata.go" -debug internal/render/templates/ instead.