diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 84a35d3..b483846 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -51,6 +51,7 @@ jobs:
         id: refs
         run: |
           set -ex
+          env
           go run ./cmd/build evaluate-environment --log.colorMode=always
 
   test:
diff --git a/cmd/build/base.go b/cmd/build/base.go
index 48e821b..e8fa848 100644
--- a/cmd/build/base.go
+++ b/cmd/build/base.go
@@ -88,7 +88,7 @@ func (this *base) init(ctx context.Context, app *kingpin.Application) {
 		PlaceHolder("<filename>").
 		StringVar(&this.optionsOutputFilename)
 	app.Flag("summaryOutputFilename", "").
-		Envar("$GITHUB_STEP_SUMMARY").
+		Envar("GITHUB_STEP_SUMMARY").
 		PlaceHolder("<filename>").
 		StringVar(&this.summaryOutputFilename)