diff --git a/.appveyor.yml b/.appveyor.yml
index bf132aeaa8..f6492f5830 100644
--- a/.appveyor.yml
+++ b/.appveyor.yml
@@ -12,8 +12,6 @@ version: '{build}'
 
 os:
   - Visual Studio 2022
-  - Visual Studio 2019
-  - Visual Studio 2015
 
 platform:
   - x64
@@ -26,17 +24,38 @@ build:
 
 environment:
   CMAKE_INSTALL_PREFIX: C:\projects\stir\install\
+  DEPS: C:\projects\deps
+  sccache_VER: 0.3.3
+
+install:
+  - IF NOT EXIST %DEPS% mkdir %DEPS%
+  - cd %DEPS%
+  - set sccache_FULLNAME="sccache-v%sccache_VER%-x86_64-pc-windows-msvc"
+  - set sccache_URL="https://github.com/mozilla/sccache/releases/download/v%sccache_VER%/%sccache_FULLNAME%.zip"
+  - IF NOT EXIST %DEPS%\sccache-%sccache_VER%.zip appveyor DownloadFile %sccache_URL% -FileName sccache-%sccache_VER%.zip
+  - IF NOT EXIST %DEPS%\sccache.exe 7z x sccache-%sccache_VER%.zip -o%DEPS%\
+  - IF NOT EXIST %DEPS%\sccache.exe move %sccache_FULLNAME%\*.* .
 
 build_script:
+  - cd C:\projects\STIR
+  - REM path=%path%;%DEPS%
+  - REM sccache --show-stats
   # find boost on Appveyor. Version depends on VM
   - for /D %%d in (C:\Libraries\boost_*) do set BOOST_ROOT=%%d
   - echo Using Boost %BOOST_ROOT%
   - mkdir build
   - mkdir install
   - cd build
-  - cmake.exe .. -DCMAKE_INSTALL_PREFIX="C:\projects\stir\install" -DCMAKE_BUILD_TYPE=%CONFIGURATION%  -DCMAKE_CONFIGURATION_TYPES=%CONFIGURATION% -DSTIR_OPENMP:BOOL=ON -DBUILD_DOCUMENTATION:BOOL=OFF
+  - cmake --version
+  - cmake.exe .. -G Ninja -DCMAKE_INSTALL_PREFIX=%CMAKE_INSTALL_PREFIX% -DCMAKE_BUILD_TYPE=%CONFIGURATION%  -DCMAKE_CONFIGURATION_TYPES=%CONFIGURATION% -DSTIR_OPENMP=ON -DBUILD_DOCUMENTATION:BOOL=OFF
+  - REM DCMAKE_C_COMPILER_LAUNCHER=sccache -DCMAKE_CXX_COMPILER_LAUNCHER=sccache
   - cmake.exe --build . --config %CONFIGURATION%
   - cmake.exe --build . --target install --config %CONFIGURATION%
+  - REM sccache --show-stats
+
+cache:
+  - c:\projects\deps\sccache-%sccache_VER%.zip
+  # - C:\Users\appveyor\AppData\Local\Mozilla\sccache\cache
 
 test_script:
   - cd C:\projects\stir\build
diff --git a/src/buildblock/getopt.c b/src/buildblock/getopt.c
index fff1f5164c..45f20b6160 100644
--- a/src/buildblock/getopt.c
+++ b/src/buildblock/getopt.c
@@ -202,11 +202,7 @@ static char *posixly_correct;
 # define my_index       strchr
 #else
 
-# if HAVE_STRING_H || WIN32 /* Pete Wilson mod 7/28/02 */
-#  include <string.h>
-# else
-#  include <strings.h>
-# endif
+#include <string.h>
 
 /* Avoid depending on library functions or files
    whose names are inconsistent.  */