diff --git a/go/buildstep/failure.go b/go/buildstep/failure.go
index 446c097..98100fa 100644
--- a/go/buildstep/failure.go
+++ b/go/buildstep/failure.go
@@ -31,10 +31,6 @@ type Failure struct {
 	Output string `json:"output,omitempty"`
 }
 
-// Version is the version of this contract a build module names in its result (Result.Contract): 1 is the first, a
-// failure with a Cause that is never a passing line and an Output of the failing test's own lines.
-const Version = 1
-
 // OutputBytes is the most a failure keeps of its output, and LineBytes the most of one line: four kilobytes holds a long
 // assertion message and stays far under a bus message's or a verdict's bound.
 const (