diff --git a/CONTRIBUTING.md b/CONTRIBUTING.md
index 46c0f9305..14a271ea6 100644
--- a/CONTRIBUTING.md
+++ b/CONTRIBUTING.md
@@ -33,19 +33,23 @@ Like Linux, Git treats filenames as arbitrary bytestrings. There is no prescribe
 encoding for these strings, and although it is fairly common to use UTF-8, any
 raw byte strings are supported.
 
-For this reason, Dulwich internally treats git-based filenames as bytestrings. It is up
-to the Dulwich API user to encode and decode them if necessary.
+For this reason, Dulwich internally treats git-based filenames as bytestrings.
+It is up to the Dulwich API user to encode and decode them if necessary. In the
+future, the porcelain may accept unicode strings and convert them to bytestrings
+as necessary on the fly (using sys.getfilesystemencoding()).
 
 * git-repository related filenames: bytes
 * object sha1 digests (20 bytes long): bytes
-* object sha1 hexdigests (40 bytes long): str (bytestrings on python2, strings on python3)
+* object sha1 hexdigests (40 bytes long): str (bytestrings on python2, strings
+  on python3)
 
 Merge requests
 --------------
-Please either send pull requests to the maintainer (jelmer@jelmer.uk) or create new pull
-requests on GitHub.
+Please either send pull requests to the maintainer (jelmer@jelmer.uk) or create
+new pull requests on GitHub.
 
 Licensing
 ---------
-All contributions should be made under the same license that Dulwich itself comes under:
-both Apache License, version 2.0 or later and GNU General Public License, version 2.0 or later.
+All contributions should be made under the same license that Dulwich itself
+comes under: both Apache License, version 2.0 or later and GNU General Public
+License, version 2.0 or later.