diff --git a/sd/sd.go b/sd/sd.go
new file mode 100644
index 0000000..71da211
--- /dev/null
+++ b/sd/sd.go
@@ -0,0 +1,24 @@
+package sd
+
+import (
+	"context"
+)
+
+type Options struct{}
+
+type Option func(opts *Options)
+
+type Service struct {
+	Node    string
+	Name    string
+	Network string
+	Address string
+}
+
+// SD is the service discovery interface.
+type SD interface {
+	Register(ctx context.Context, name string, network string, address string, opts ...Option) error
+	Deregister(ctx context.Context, name string) error
+	Renew(ctx context.Context, name string) error
+	Get(ctx context.Context, name string) ([]*Service, error)
+}