diff --git a/CMakeLists.txt b/CMakeLists.txt
index 87e6c66..641244c 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -57,6 +57,9 @@ include(VersionFeather)
 
 #### Dependencies
 # Monero
+if (NOT EXISTS "${CMAKE_CURRENT_SOURCE_DIR}/monero/CMakeLists.txt")
+    message(FATAL_ERROR "'monero/CMakeLists.txt' does not exist, did you forget to:\ngit submodule update --init --recursive")
+endif()
 add_subdirectory(monero EXCLUDE_FROM_ALL)
 set_property(TARGET wallet_merged PROPERTY FOLDER "monero")
 get_directory_property(ARCH_WIDTH DIRECTORY "monero" DEFINITION ARCH_WIDTH)
diff --git a/contrib/guix/guix-build b/contrib/guix/guix-build
index b7707bc..d9ab5cf 100755
--- a/contrib/guix/guix-build
+++ b/contrib/guix/guix-build
@@ -47,6 +47,12 @@ EOF
 exit 1
 fi
 
+################
+# Checkout git submodules if we haven't already
+################
+
+git submodule update --init --recursive
+
 ################
 # The git worktree should not be dirty
 ################