diff --git a/private/racket-webview.rkt b/private/racket-webview.rkt
index dd67524..dab6b94 100644
--- a/private/racket-webview.rkt
+++ b/private/racket-webview.rkt
@@ -116,6 +116,7 @@
    [request-count #:mutable]
    [sec-token-cache #:mutable]
    [cert-ou-token #:mutable]
+   [context #:mutable]
    )
   #:transparent)
 
@@ -225,10 +226,13 @@
                  )
                 )
               ) 
-      (let* ((f1 "c:/tmp/my.crt")
-             (f2 "c:/tmp/my.key")
-             (fh1 (open-output-file f1 #:exists 'replace))
-             (fh2 (open-output-file f2 #:exists 'replace)))
+      (let* ((cert-path (let ((p (build-path (find-system-path 'pref-dir) "racket-webview" (wv-context h))))
+                          (make-directory* p)
+                          p))
+             (f1 (build-path cert-path "self-signed.cert"))
+             (f2 (build-path cert-path "self-signed.key"))
+             (fh1 (open-output-file f1 #:exists 'replace #:permissions #o600))
+             (fh2 (open-output-file f2 #:exists 'replace #:permissions #o600)))
         (display (certificate cert) fh1)
         (display (private-key cert) fh2)
         (close-output-port fh1)
@@ -353,11 +357,14 @@
 ;; Webview functions
 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
    
-(define (webview-create file-getter event-callback
-                        #:boilerplate-js [bj (λ () (default-boilerplate-js))]
-                        #:parent [p #f])
+(define/contract (webview-create context file-getter event-callback
+                                 #:boilerplate-js [bj (λ () (default-boilerplate-js))]
+                                 #:parent [p #f])
+  (->* ((or/c symbol? string?) procedure? procedure?)
+       (#:boilerplate-js procedure? #:parent (or/c wv? #f))
+       wv?)
   (let* ((h (make-wv #f 0 -1 file-getter bj #f 0 (make-lru 250 #:cmp eq?)
-                     (symbol->string (make-security-token))))
+                     (symbol->string (make-security-token)) (symbol->string context)))
          (cert (generate-self-signed-cert 2048 365 '("127.0.0.1" "localhost")
                                           "NL" "Dijkema"
                                           #:ou (wv-cert-ou-token h)))
@@ -771,7 +778,7 @@
 (define (test)
   (let* ((cb (λ (handle evt)
                (displayln evt)))
-         (h (webview-create file-getter cb))
+         (h (webview-create 'test file-getter cb))
          )
     (webview-set-title! h "This is a test window")
     (webview-resize h 800 600)