diff --git a/.bazelrc b/.bazelrc
index f83a19b89..ed7c1cde2 100644
--- a/.bazelrc
+++ b/.bazelrc
@@ -2,7 +2,7 @@ common --enable_platform_specific_config
 common --experimental_repository_cache_hardlinks
 
 # specify python path for pyo3 compile
-build:windows --action_env="PYTHON_SYS_EXECUTABLE=c:\\python\\python.exe"
+build:windows --action_env="PYTHON_SYS_EXECUTABLE=c:/python/python.exe"
 #build:linux --action_env="PYTHON_SYS_EXECUTABLE=/usr/local/bin/python3.8"
 
 # runfiles are off by default on Windows, and we need them
diff --git a/.bazelversion b/.bazelversion
index 7c69a55db..fcdb2e109 100644
--- a/.bazelversion
+++ b/.bazelversion
@@ -1 +1 @@
-3.7.0
+4.0.0