Sift

▶ Live demo — apps.charliekrug.com/shell-alias-miner

The aliases hiding in your shell history.

Point Sift at your own shell history and it mines your most-repeated multi-word commands, proposes ready-to-paste aliases and shell functions for them, and tells you exactly how many keystrokes each one will save you.

History search tools help you find a command again. Sift closes the loop: it finds the commands you keep retyping and hands you the alias so you never have to.

Everything runs locally in your browser. The miner is a Go program compiled to WebAssembly, so your shell history is never uploaded anywhere.

Why

Most of us have a handful of long, awkward commands we type dozens or hundreds of times a year: a git log incantation, a docker run with the same six flags, an ffmpeg transcode. We know we should alias them. We never get around to figuring out which ones are worth it, or what the alias should even look like. Sift does that analysis for you in under a second.

The wow moment

Drop your .zsh_history (or .bash_history) onto the page. Within a second it shows you the exact command you typed 340 times this year, a ready-to-paste alias line, and the math on how many keystrokes that alias will save you going forward.

How it works

Sift doesn't just count identical lines. It tokenizes each history entry and mines repeated n-gram patterns across commands, so it catches a command you run constantly with varying arguments (for example git commit -m "..." with a different message every time) as a single candidate, not hundreds of "unique" lines.

For every candidate pattern it proposes either:

• a plain alias when the command has no varying arguments, or
• a shell function with a positional parameter when arguments vary.

Each proposal comes with a keystrokes-saved estimate: (chars typed per use - chars typed with the alias) x times seen.

Sample output

Alias	Type	Definition	Seen	Keystrokes saved
gs	alias	alias gs="git status --short --branch"	340	9,860
gc	function	function gc() { git commit -m "$1"; }	128	1,664
dcu	alias	alias dcu="docker compose up -d"	58	1,392
gl	alias	alias gl="git log --oneline --graph --all"	21	861

Features

• Parses .zsh_history (with and without the EXTENDED_HISTORY timestamp format) and plain .bash_history.
• Drag-and-drop the file onto the page, or use the file picker.
• Frequency and n-gram mining over tokenized command lines, not raw string matching. Commands that vary only in a trailing argument (a commit message, a filename) are recognized as one repeated pattern.
• Ranks candidates by total keystrokes saved, not just raw frequency.
• Proposes alias for fixed commands and function for commands with varying arguments; a "Type" column shows which is which.
• Adjustable minimum-occurrence and minimum-savings thresholds, applied instantly without re-mining.
• One-click copy of the generated alias/function block, with an info affordance that explains the keystrokes-saved math per row.
• Never proposes an alias/function that would bake in a password, token, or other inline credential.
• Everything runs client-side via WebAssembly. No server, no upload, no network request.

Stack

• Go, compiled to GOOS=js GOARCH=wasm, is the mining engine and parser.
• A minimal static HTML/CSS/JS shell loads the wasm module and drives the UI (file picker, results table, copy-to-clipboard).
• No backend and no build server required at runtime; the wasm binary is a static asset.

Building and running locally

make test    # run the Go test suite
make test-js # run site/main.js's unit tests (needs Node)
make vet     # go vet, including the wasm entrypoint
make site    # build site/main.wasm and copy in wasm_exec.js

After make site, serve site/ with any static file server (opening index.html directly via file:// won't work, because fetch() requires http(s)) and open it in a browser, for example:

cd site && python3 -m http.server 8080

Documentation

• docs/VISION.md for the full design rationale.
• docs/ARCHITECTURE.md for how the pieces fit together.
• docs/DESIGN.md for the site's visual direction.
• docs/BACKLOG.md for what's shipped and what's left.

License

MIT, see LICENSE.

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More of Charlie's projects → apps.charliekrug.com