diff --git a/cmake/cmkr.cmake b/cmake/cmkr.cmake
index 15af102..bcc15cf 100644
--- a/cmake/cmkr.cmake
+++ b/cmake/cmkr.cmake
@@ -10,6 +10,7 @@ if(CMAKE_SCRIPT_MODE_FILE)
     set(CMAKE_BINARY_DIR "${CMAKE_BINARY_DIR}/build")
     set(CMAKE_CURRENT_BINARY_DIR "${CMAKE_BINARY_DIR}")
     file(MAKE_DIRECTORY "${CMAKE_BINARY_DIR}")
+    file(WRITE "${CMAKE_BINARY_DIR}/.gitignore" "# This file is autogenerated by cmkr.\n*\n")
 endif()
 
 # Set these from the command line to customize for development/debugging purposes