How to read very large files in Go without OOM errors.

To handle files larger than available RAM, use streaming techniques via the io.Reader interface and bufio.Scanner.

os.ReadFile loads the entire file into a byte slice, destroying memory if the file is 10GB. Instead, bufio.Scanner or bufio.Reader reads the file line-by-line (or chunk-by-chunk) into a small, fixed-size buffer, keeping the application's memory footprint tiny and flat.