diff --git a/go/vendor/github.com/go-openapi/swag/post_go19.go b/go/vendor/github.com/go-openapi/swag/post_go19.go
new file mode 100644
index 0000000..567680c
--- /dev/null
+++ b/go/vendor/github.com/go-openapi/swag/post_go19.go
@@ -0,0 +1,53 @@
+// +build go1.9
+
+package swag
+
+import (
+	"sort"
+	"sync"
+)
+
+// indexOfInitialisms is a thread-safe implementation of the sorted index of initialisms.
+// Since go1.9, this may be implemented with sync.Map.
+type indexOfInitialisms struct {
+	sortMutex *sync.Mutex
+	index     *sync.Map
+}
+
+func newIndexOfInitialisms() *indexOfInitialisms {
+	return &indexOfInitialisms{
+		sortMutex: new(sync.Mutex),
+		index:     new(sync.Map),
+	}
+}
+
+func (m *indexOfInitialisms) load(initial map[string]bool) *indexOfInitialisms {
+	m.sortMutex.Lock()
+	defer m.sortMutex.Unlock()
+	for k, v := range initial {
+		m.index.Store(k, v)
+	}
+	return m
+}
+
+func (m *indexOfInitialisms) isInitialism(key string) bool {
+	_, ok := m.index.Load(key)
+	return ok
+}
+
+func (m *indexOfInitialisms) add(key string) *indexOfInitialisms {
+	m.index.Store(key, true)
+	return m
+}
+
+func (m *indexOfInitialisms) sorted() (result []string) {
+	m.sortMutex.Lock()
+	defer m.sortMutex.Unlock()
+	m.index.Range(func(key, value interface{}) bool {
+		k := key.(string)
+		result = append(result, k)
+		return true
+	})
+	sort.Sort(sort.Reverse(byLength(result)))
+	return
+}