Utilities
Lessons filed under Utilities.
Utilities Build a password generator Build a password generator in the shell, step by step, and count the bits behind every secret it prints.
Utilities Build an encoder and decoder Build an encoder and decoder in the shell, step by step, and learn to check a decode instead of trusting it.
Utilities Build a hash and checksum tool Grow a one-line sha256sum into a real checksum tool, step by step, then copy the finished script.
Utilities Build a JWT inspector Grow a single cut command into a token inspector, step by step, then copy the finished script.
Utilities Build a permissions calculator Read a mode from stat, turn octal into rwx and back, get the special bits right, and finish with a complete script you can keep.
Utilities Build a subnet calculator Convert an address to a number, build the mask, work out the network and broadcast with bitwise arithmetic, and finish with a complete script you can keep.