diff --git a/src/git.xdrm.io/schastsp/client/client.go b/src/git.xdrm.io/schastsp/client/client.go
index c83119c..ec0a673 100644
--- a/src/git.xdrm.io/schastsp/client/client.go
+++ b/src/git.xdrm.io/schastsp/client/client.go
@@ -34,6 +34,7 @@ func New(ctx *context.T, saveDir string) (*T, error) {
 	inst := new(T)
 
 	/* (1) Store context */
+	if ctx == nil { return nil, errors.New("Context must not be nil"); }
 	inst.ctx = ctx
 
 	/* (2) Get file management for KEY */