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🐚 Bash One-Liner Generator

Build common bash one-liners without memorizing the syntax. Pick a task, fill in the blanks, copy the command.

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About this tool

A catalog of bash one-liners for the tasks developers reach for again and again — kill the process on a port, find the largest files in a directory, recursive find-and-replace, mirror a website, extract an archive, prune merged git branches. Pick a task, fill in the blanks, copy the command.

Example: pick "Kill the process listening on a port", enter 3000, and you get lsof -ti:3000 | xargs kill -9. Pick "Find the largest files in a directory", enter . and 20, and you get du -ah . | sort -rh | head -n 20.

Each command comes with a short explanation of what each piece does and a warning when an operation modifies files in place, so you understand the line before you paste it into a terminal.

FAQ

Are these commands safe to run?

Each entry explains what the command does and warns when it modifies files (e.g. find-and-replace with sed -i). Read the explanation first, and on commands flagged as in-place edits, test without the -i flag so you can preview the result.

Linux or macOS — do they work on both?

Yes for almost all entries. Where there is a meaningful difference (such as sed -i needing an empty backup suffix on macOS), the explanation notes it. Windows users should run these in WSL or Git Bash.

Why not just use ChatGPT for this?

You can. This tool exists for the dozen or so commands almost every developer ends up looking up repeatedly — having them as a fast, offline catalog with copy buttons is quicker than typing a prompt and waiting for an answer.

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