diff --git a/.golangci.yml b/.golangci.yml
index e3400d6..7886c7c 100644
--- a/.golangci.yml
+++ b/.golangci.yml
@@ -10,6 +10,7 @@ linters:
   enable:
     - errcheck
     - errname
+    - gochecksumtype
     - govet
     - ineffassign
     - revive
diff --git a/internal/schema/ast/ast.go b/internal/schema/ast/ast.go
index d01359a..caa8570 100644
--- a/internal/schema/ast/ast.go
+++ b/internal/schema/ast/ast.go
@@ -377,6 +377,8 @@ func (r *Ref) End() token.Position {
 }
 
 // Name is an IDENT or STR
+//
+//sumtype:decl
 type Name interface {
 	Node
 	isName()