diff --git a/.travis.yml b/.travis.yml
old mode 100644
new mode 100755
index a77f25a..bf57916
--- a/.travis.yml
+++ b/.travis.yml
@@ -1,4 +1,7 @@
 language: python
+os:
+  - linux
+  - osx
 notifications:
   email: false
 python:
diff --git a/README.md b/README.md
old mode 100644
new mode 100755
index 6318f01..94e34a4
--- a/README.md
+++ b/README.md
@@ -17,6 +17,9 @@ HandshakeState, CipherState and SymmetricState. Refer to the rest of the README
 
 ## Installation and prerequisites
 For now, only Python 3.5+ is supported.
+The author provides support for Linux systems only. Although the CI systems perform testing on **Windows and OS X**, consider their support even **more experimental** than the whole package, though OS X usage should not differ from Linux.
+
+*Unless there is a dedicated contributor for Windows, the author won't provide any support for issues with using the noiseprotocol package on them. Python development on Windows is too painful, even considering my deep love for the OS.*
 
 Install via pip:
 ```
diff --git a/appveyor.yml b/appveyor.yml
index 97842f9..01ea965 100755
--- a/appveyor.yml
+++ b/appveyor.yml
@@ -7,7 +7,7 @@ environment:
 
 install:
   - "%PYTHON%\\python.exe -m pip install -r requirements.txt"
-  - "%PYTHON%\\python.exe -m pip install pytest"
+  - "%PYTHON%\\python.exe -m pip install pytest wheel"
 
 build: off
 
diff --git a/setup.py b/setup.py
old mode 100644
new mode 100755
index 2f5735f..93027fd
--- a/setup.py
+++ b/setup.py
@@ -29,6 +29,9 @@ setup(
         'Programming Language :: Python :: 3.5',
         'Programming Language :: Python :: 3.6',
         # 'Programming Language :: Python :: 3.7',
+        'Operating System :: MacOS :: MacOS X',
+        'Operating System :: Microsoft :: Windows',
+        'Operating System :: POSIX :: Linux'
     ],
     keywords='cryptography noiseprotocol noise security',
     packages=find_packages(exclude=['contrib', 'docs', 'tests', 'examples']),