diff --git a/cmd/nanomdm/main.go b/cmd/nanomdm/main.go
index c0d14dd..033b491 100644
--- a/cmd/nanomdm/main.go
+++ b/cmd/nanomdm/main.go
@@ -213,7 +213,7 @@ func main() {
 // Currently this just makes a random string. This would be better
 // served by e.g. https://github.com/oklog/ulid or something like
 // https://opentelemetry.io/ someday.
-func newTraceID() string {
+func newTraceID(_ *http.Request) string {
 	b := make([]byte, 8)
 	rand.Read(b)
 	return fmt.Sprintf("%x", b)
diff --git a/http/http.go b/http/http.go
index 531a7a0..81849d9 100644
--- a/http/http.go
+++ b/http/http.go
@@ -53,10 +53,13 @@ type ctxKeyTraceID struct{}
 
 // TraceLoggingMiddleware sets up a trace ID in the request context and
 // logs HTTP requests.
-func TraceLoggingMiddleware(next http.Handler, logger log.Logger, newTrace func() string) http.HandlerFunc {
+func TraceLoggingMiddleware(next http.Handler, logger log.Logger, newTrace func(*http.Request) string) http.HandlerFunc {
 	return func(w http.ResponseWriter, r *http.Request) {
-		ctx := context.WithValue(r.Context(), ctxKeyTraceID{}, newTrace())
-		ctx = ctxlog.AddFunc(ctx, ctxlog.SimpleStringFunc("trace_id", ctxKeyTraceID{}))
+		ctx := r.Context()
+		if newTrace != nil {
+			ctx = context.WithValue(r.Context(), ctxKeyTraceID{}, newTrace(r))
+			ctx = ctxlog.AddFunc(ctx, ctxlog.SimpleStringFunc("trace_id", ctxKeyTraceID{}))
+		}
 
 		host, _, err := net.SplitHostPort(r.RemoteAddr)
 		if err != nil {