diff --git a/test/regexp-fail.rkt b/test/regexp-fail.rkt
index 81ca8e7..578d6c8 100644
--- a/test/regexp-fail.rkt
+++ b/test/regexp-fail.rkt
@@ -40,20 +40,34 @@
   ;; --- can't handle starred groups
   (ann (regexp-match: "(a)*(b)" "b")
        (U #f (List String String)))
-) (test-compile-error
-  #:require trivial/regexp
-  #:exn #rx"mutation not allowed"
-  ;; -- set! problems
-  (ann (let-regexp: ([a #rx"(b)(B)"])
-         (set! a #rx"")
-         (regexp-match: a "hai"))
-       (List String String String))
-  (let ()
-    (define-regexp: a #rx"h(i)")
-    (set! a #rx"hi")
-    (regexp-match a "hi"))
+)
 
-  (let-regexp: ([a #rx"h(i)"])
-    (set! a #rx"(h)(i)")
-    (regexp-match a "hi"))
-))
+(test-compile-error
+  #:require trivial/regexp racket/port
+  #:exn #rx"Type Checker"
+  ;; -- expected String, given Bytes
+  (with-input-from-string "hello"
+    (lambda ()
+      (define m (regexp-match #rx#"lang" (current-input-port)))
+      (and m (string=? (car m) "lang"))))
+)
+
+;; 2016-06-13 : these really should be errors, just no-opts
+;(test-compile-error
+;  #:require trivial/regexp
+;  #:exn #rx"mutation not allowed"
+;  ;; -- set! problems
+;  (ann (let-regexp: ([a #rx"(b)(B)"])
+;         (set! a #rx"")
+;         (regexp-match: a "hai"))
+;       (List String String String))
+;  (let ()
+;    (define-regexp: a #rx"h(i)")
+;    (set! a #rx"hi")
+;    (regexp-match a "hi"))
+;
+;  (let-regexp: ([a #rx"h(i)"])
+;    (set! a #rx"(h)(i)")
+;    (regexp-match a "hi"))
+;)
+)
diff --git a/test/regexp-pass.rkt b/test/regexp-pass.rkt
index 1e42ac8..4e25382 100644
--- a/test/regexp-pass.rkt
+++ b/test/regexp-pass.rkt
@@ -8,11 +8,18 @@
     trivial/regexp
     typed/rackunit)
 
-  ;; -- TODO
+  ;; -- TODO (handle regexp . format)
   ; (define re:normal-name (regexp (format "~a*<([^>]*)>~a*" blank blank)))
 
   ;; -- regexps, from the world
 
+  (let ([str 
+
+  (let () ;; -- from klocker? anyway the unicode will segfault `unsafe-string-ref`
+    (check-equal?
+      (ann (regexp-match: #rx"⇒" "yolo") (U #f (List String)))
+      #f))
+
   (let ([str "dont care"]) ;; from `tests/racket/contract/multi-file.rkt`
     (check-equal?
       (ann
diff --git a/trivial/private/parameters.rkt b/trivial/private/parameters.rkt
index 37bab4c..ef01dc3 100644
--- a/trivial/private/parameters.rkt
+++ b/trivial/private/parameters.rkt
@@ -9,7 +9,7 @@
 ;; =============================================================================
 
 (: *TRIVIAL-LOG* (Parameterof Boolean))
-(define *TRIVIAL-LOG* (make-parameter #t))
+(define *TRIVIAL-LOG* (make-parameter #f))
 
 (: *STOP-LIST* (Parameterof (Listof Identifier)))
 (define *STOP-LIST* (make-parameter '()))
diff --git a/trivial/private/regexp.rkt b/trivial/private/regexp.rkt
index e68a28f..949329d 100644
--- a/trivial/private/regexp.rkt
+++ b/trivial/private/regexp.rkt
@@ -34,7 +34,6 @@
     typed/racket/base
     (only-in racket/list range)
     (only-in racket/format ~a)
-    (only-in racket/unsafe/ops unsafe-string-ref)
     syntax/parse
     trivial/private/common))
 
@@ -155,7 +154,7 @@
     (define h-rev
       (for/fold ([hist (for/hasheq ([c (in-list c*)]) (values c '()))])
                 ([i (in-range L)])
-        (define char (unsafe-string-ref str i))
+        (define char (string-ref str i))
         (cond
          [(unbox escaped?)
           (when (or (not (eq? #\\ char))