diff --git a/Dockerfile b/Dockerfile
index bdbc8b746..72b4bba3c 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -17,7 +17,8 @@ COPY go.sum .
 RUN go mod download
 
 COPY . .
-RUN make clean install assets build
+RUN make clean install assets
+RUN AUDI_HASH_SECRET={{ env "AUDI_HASH_SECRET" }} make build
 
 #
 # STEP 2 build a small image including module support
diff --git a/docker/tmpl.Dockerfile b/docker/tmpl.Dockerfile
index 08b10e4a5..753e07900 100644
--- a/docker/tmpl.Dockerfile
+++ b/docker/tmpl.Dockerfile
@@ -17,7 +17,7 @@ RUN go mod download
 
 COPY . .
 RUN make clean install assets
-RUN GOARCH={{ .GoARCH }} GOARM={{ .GoARM }} make build
+RUN GOARCH={{ .GoARCH }} GOARM={{ .GoARM }} AUDI_HASH_SECRET={{ env "AUDI_HASH_SECRET" }} make build
 
 #############################
 ## STEP 2 build a small image
diff --git a/vehicle/audi.go b/vehicle/audi.go
index 16586a450..054293741 100644
--- a/vehicle/audi.go
+++ b/vehicle/audi.go
@@ -133,8 +133,8 @@ func (v *Audi) authFlow() error {
 		})
 
 		var hash string
-		var secret []byte
-		if secret, err = hex.DecodeString(AudiHashSecret); err == nil {
+		secret, err := hex.DecodeString(AudiHashSecret)
+		if err == nil {
 			// timestamp rounded to 100s precision
 			ts := strconv.FormatInt(time.Now().Unix()/100, 10)