diff --git a/Makefile b/Makefile
index 6ac5153d2..1e5495e00 100644
--- a/Makefile
+++ b/Makefile
@@ -44,6 +44,8 @@ test:
 test-emscripten:
 	cargo test --manifest-path lib/emscripten/Cargo.toml --features clif -- --test-threads=1 $(runargs)
 	cargo test --manifest-path lib/emscripten/Cargo.toml --features llvm -- --test-threads=1 $(runargs)
+	cargo test --manifest-path lib/emscripten/Cargo.toml _vfs --features clif,vfs -- --test-threads=1 $(runargs)
+	cargo test --manifest-path lib/emscripten/Cargo.toml _vfs --features llvm,vfs -- --test-threads=1 $(runargs)
 
 release:
 	# If you are in OS-X, you will need mingw-w64 for cross compiling to windows