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Working with files, terminal and AI on a Mac.
Compare text files on a Mac and see only what changed
How to compare text files on a Mac with what is already installed, the five reasons identical-looking files differ, and what the paid and web tools are actually buying.
Connect to a server from a Mac: the address is half the problem
Mac connect to server, without the guesswork: the two routes the Finder offers, the address formats Apple documents, and how to make a mount come back.
Brew install PostgreSQL on a Mac, and where the data folder lands
What brew install postgresql really installs, why psql is missing from PATH afterwards, where the data directory lands, and what a major upgrade costs.
Brew install the AWS CLI and keep its credentials straight
brew install aws cli takes one line. The work is what comes after: a second copy of aws on PATH, and ten places credentials can load from in a fixed order.
Brew update: what it changes and what it leaves alone
brew update refreshes the catalogue and installs nothing. What it touches, what brew upgrade drags along, and which environment variables decide the rest.
Change a Git commit message after you have committed
How to git change a commit message: amend the last one, reword an older one, what force pushing costs, and the one case rewriting does not clean up.
Checkout a remote branch in Git and keep it tracked
How to checkout a remote branch in Git, why the name is sometimes not found, when the shortcut quietly fails, and how to confirm tracking was set.
Chmod 777: why it works and why you should stop reaching for it
777 chmod works because it removes the permission check entirely. What each digit grants, the three bits it silently clears, and what to run instead on macOS.