diff --git a/src/compiler.shen b/src/compiler.shen
index bd906bd..68820e5 100644
--- a/src/compiler.shen
+++ b/src/compiler.shen
@@ -22,7 +22,6 @@
          (set *static-globals* [
            shen.*infs* shen.*call* shen.*occurs*
            shen.*special* shen.*extraspecial*
-           shen.*platform-native-call-check*
            shen.*demodulation-function*
            shen.*gensym*
            *stinput* *stoutput* *sterror*
diff --git a/src/init.scm b/src/init.scm
index a80df0a..6c4908f 100644
--- a/src/init.scm
+++ b/src/init.scm
@@ -5,8 +5,6 @@
 (kl:set '*implementation* "chez-scheme")
 (kl:set '*release* (call-with-values scheme-version-number (lambda (major minor patch) (format "~s.~s.~s" major minor patch))))
 (kl:set '*porters* "Bruno Deferrari")
-(kl:set '*home-directory* (current-directory))
-(kl:set 'shen.*initial-home-directory* (current-directory))
 
 (register-globals)
 
@@ -14,14 +12,4 @@
 (kl:global/*stinput* (standard-input-port))
 (kl:global/*stoutput* (standard-output-port))
 
-(kl:global/shen.*platform-native-call-check*
-  (lambda (fname)
-    (and (symbol? fname)
-         (let ((fname (symbol->string fname)))
-           (and (>= (string-length fname) 4)
-                (char=? #\. (string-ref fname 3))
-                (char=? #\s (string-ref fname 0))
-                (char=? #\c (string-ref fname 1))
-                (char=? #\m (string-ref fname 2)))))))
-
 (kl:_scm.initialize-compiler)
diff --git a/src/overrides.shen b/src/overrides.shen
index 42e4787..53142e1 100644
--- a/src/overrides.shen
+++ b/src/overrides.shen
@@ -1,11 +1,6 @@
 \* Copyright (c) 2012-2021 Bruno Deferrari.  All rights reserved. *\
 \* BSD 3-Clause License: http://opensource.org/licenses/BSD-3-Clause *\
 
-(define cd
-  "" -> (cd (value shen.*initial-home-directory*))
-  Dir -> (let NewDir ((foreign scm.current-directory) Dir)
-           (set *home-directory* ((foreign scm.current-directory)))))
-
 (define hash
   Val Bound -> ((foreign scm.fxmod) ((foreign scm.equal-hash) Val) Bound))
 
@@ -91,13 +86,10 @@
 \* read-file-as-* defined in prelude.scm *\
 
 (define read-file-as-bytelist
-  Filename -> ((foreign scm.read-file-as-bytelist) Filename))
-
-(define shen.read-file-as-charlist
-  Filename -> ((foreign scm.read-file-as-bytelist) Filename))
+  Filename -> ((foreign scm.read-file-as-bytelist) ((foreign scm.string-append) (value *home-directory*) Filename)))
 
 (define read-file-as-string
-  Filename -> ((foreign scm.read-file-as-string) Filename))
+  Filename -> ((foreign scm.read-file-as-string) ((foreign scm.string-append) (value *home-directory*) Filename)))
 
 \* tuples *\
 
diff --git a/src/primitives.scm b/src/primitives.scm
index 2db3ce3..fc89bac 100644
--- a/src/primitives.scm
+++ b/src/primitives.scm
@@ -122,8 +122,11 @@
 ;; Streams and I/O
 ;;
 
+(define (with-home-directory filename)
+  (string-append (kl:value '*home-directory*) filename))
+
 (define (kl:open filename direction)
-  (let ((full-path (full-path-for-file filename)))
+  (let ((full-path (full-path-for-file (with-home-directory filename))))
     (case direction
       ((in) (if (file-exists? full-path)
                 (open-binary-input-file full-path)