diff --git a/internal/app/server.go b/internal/app/server.go
index 062bdcd..b6a6c7c 100644
--- a/internal/app/server.go
+++ b/internal/app/server.go
@@ -10,10 +10,25 @@ type Server struct {
 	proto.UnsafeSmmCoreServer
 }
 
-func NewServer() *Server {
+func NewServer() proto.SmmCoreServer {
 	return &Server{}
 }
 
 func (s *Server) Ping(_ context.Context, _ *proto.PingReq) (*proto.PingRsp, error) {
 	return &proto.PingRsp{}, nil
 }
+
+// AddCategory implements proto.SmmCoreServer.
+func (s *Server) AddCategory(context.Context, *proto.CreateCategoryReq) (*proto.Category, error) {
+	panic("unimplemented")
+}
+
+// GetCategories implements proto.SmmCoreServer.
+func (s *Server) GetCategories(context.Context, *proto.CategoryFilterReq) (*proto.Categories, error) {
+	panic("unimplemented")
+}
+
+// UpdateCategory implements proto.SmmCoreServer.
+func (s *Server) UpdateCategory(context.Context, *proto.UpdateCategoryReq) (*proto.Category, error) {
+	panic("unimplemented")
+}