diff --git a/fmt.sh b/fmt.sh
new file mode 100755
index 0000000..7f07972
--- /dev/null
+++ b/fmt.sh
@@ -0,0 +1,18 @@
+#!/bin/sh
+# Custom formatter following project guidelines:
+# 1. Standard gofmt
+# 2. 2-space indentation (expand tabs)
+# 3. Report/Check 112-char limit
+
+FILES=$(find . -name "*.go" -not -path "./bin/*")
+
+for f in $FILES; do
+  gofmt -s -w "$f"
+  expand -t 2 "$f" > "$f.tmp" && mv "$f.tmp" "$f"
+done
+
+LONG_LINES=$(grep -n '.\{113,\}' $FILES)
+if [ -n "$LONG_LINES" ]; then
+  echo "Warning: The following lines exceed 112 characters:"
+  echo "$LONG_LINES"
+fi