Step-by-step macOS, Terminal, Homebrew and developer-tool guides. Every command is run on a real Mac and the actual output is shown.https://suik.me/https://suik.me/posts/check-macbook-battery-health/https://suik.me/posts/check-macbook-battery-health/Check MacBook battery health in System Settings > Battery, or run system_profiler SPPowerDataType for cycle count, condition and maximum capacity.Mon, 02 Nov 2026 00:00:00 GMThttps://suik.me/posts/generate-ssh-key-mac-github/https://suik.me/posts/generate-ssh-key-mac-github/Run ssh-keygen -t ed25519 -C "you@example.com", save the passphrase in Keychain, copy the key with pbcopy and add it to GitHub. Tested on macOS 26.Mon, 02 Nov 2026 00:00:00 GMThttps://suik.me/posts/find-large-files-mac-terminal/https://suik.me/posts/find-large-files-mac-terminal/Find large files on a Mac with find ~ -xdev -type f -size +1G, or instantly with mdfind. Tested timings, du sizing, and what is safe to delete.Mon, 02 Nov 2026 00:00:00 GMThttps://suik.me/posts/check-ram-usage-mac-terminal/https://suik.me/posts/check-ram-usage-mac-terminal/See what is using RAM on a Mac with top -l 1 -o mem, memory_pressure and vm_stat. Tested on Apple Silicon, with swap, compression and GB conversion.Mon, 02 Nov 2026 00:00:00 GMThttps://suik.me/posts/keep-mac-awake-terminal-caffeinate/https://suik.me/posts/keep-mac-awake-terminal-caffeinate/Run caffeinate -d to keep your Mac's screen on until you press Ctrl+C, or caffeinate -d -t 3600 for one hour. Every flag tested on macOS Tahoe.Mon, 02 Nov 2026 00:00:00 GMThttps://suik.me/posts/kill-process-on-port-mac/https://suik.me/posts/kill-process-on-port-mac/Find what is using a port with lsof -nP -iTCP:8080 -sTCP:LISTEN, then kill it by PID. Plus why ports 5000 and 7000 are taken by AirPlay on macOS.Mon, 02 Nov 2026 00:00:00 GMThttps://suik.me/posts/flush-dns-mac/https://suik.me/posts/flush-dns-mac/Flush DNS on macOS Tahoe with: sudo dscacheutil -flushcache; sudo killall -HUP mDNSResponder. Then check it worked, and see when flushing won't help.Mon, 02 Nov 2026 00:00:00 GMThttps://suik.me/posts/set-environment-variable-mac-permanently/https://suik.me/posts/set-environment-variable-mac-permanently/Add export MY_VAR=value to ~/.zshrc (or ~/.zprofile for PATH), then run source ~/.zshrc. Tested on macOS Tahoe with zsh 5.9, plus the temporary way.Mon, 02 Nov 2026 00:00:00 GMThttps://suik.me/posts/find-ip-address-mac-terminal/https://suik.me/posts/find-ip-address-mac-terminal/Run ipconfig getifaddr en0 to get your Mac's local IP, and curl -4 -s https://ifconfig.me for your public IP. Tested on macOS Tahoe with real output.Mon, 02 Nov 2026 00:00:00 GMThttps://suik.me/posts/git-undo-last-commit/https://suik.me/posts/git-undo-last-commit/Undo the last Git commit and keep your changes with git reset --soft HEAD~1. Tested reset modes, revert, amend, reflog recovery and pushed commits.Mon, 02 Nov 2026 00:00:00 GMThttps://suik.me/posts/show-hidden-files-mac/https://suik.me/posts/show-hidden-files-mac/Press Cmd+Shift+Period in Finder to show hidden files on Mac. Plus ls -a, the permanent defaults command, and chflags to hide or unhide any file.Mon, 02 Nov 2026 00:00:00 GMThttps://suik.me/posts/zsh-command-not-found-brew/https://suik.me/posts/zsh-command-not-found-brew/On Apple Silicon, Homebrew lives in /opt/homebrew/bin. Add eval "$(/opt/homebrew/bin/brew shellenv)" to ~/.zprofile. Fixes for python, pip, npm and code too.Mon, 02 Nov 2026 00:00:00 GMT