diff --git a/template/html/option.go b/template/html/option.go
index 31df3e3..988fa3a 100644
--- a/template/html/option.go
+++ b/template/html/option.go
@@ -33,6 +33,9 @@ func WithDefaultHelpers() OptionFunc {
 // to expose the default helpers
 func WithHelper(name string, fn interface{}) OptionFunc {
 	return func(opts *Options) {
+		if opts.Helpers == nil {
+			opts.Helpers = make(template.FuncMap)
+		}
 		opts.Helpers[name] = fn
 	}
 }