diff --git a/cranelift/src/format-all.sh b/cranelift/src/format-all.sh
new file mode 100755
index 0000000000..3569c460be
--- /dev/null
+++ b/cranelift/src/format-all.sh
@@ -0,0 +1,14 @@
+#!/bin/bash
+
+# Format all sources using rustfmt.
+
+# Exit immediately on errors.
+set -e
+
+cd $(dirname "$0")
+src=$(pwd)
+
+for crate in $(find "$src" -name Cargo.toml); do
+    cd $(dirname "$crate")
+    cargo fmt
+done