diff --git a/appveyor.yml b/appveyor.yml
index ffabea7..b95eafb 100644
--- a/appveyor.yml
+++ b/appveyor.yml
@@ -18,6 +18,13 @@ environment:
     WARNINGS_ARE_ERRORS: 1
 
   matrix:
+  - R_VERSION: devel
+    GCC_PATH: mingw_32
+
+  - R_VERSION: devel
+    R_ARCH: x64
+    GCC_PATH: mingw_64
+
   - R_VERSION: release
     R_ARCH: x64