wolysh (wsh)

A fast, readable Linux shell for developers and agent workflows.

wolysh combines everyday Linux commands with a readable scripting language. Commands stay commands; arithmetic, conditions, loops, and functions get their own syntax. It is written in Zig and uses native Linux process and job control.

Download

Get the latest Linux x86_64 release

The release archive includes the shell, examples, license, and checksum.

Interactive prompt

Why wolysh

• Run familiar commands, pipes, redirects, and globs.
• Merge stderr with stdout, feed commands with here-documents, and isolate work in subshells.
• Write scripts with expressions, if, loops, and functions.
• Use built-in completion, syntax highlighting, history suggestions, and Ctrl-R.
• Get typo suggestions with a Bloom-style prefilter; normal command lookup skips fuzzy work.
• Cache recent misses for fast inline corrections on the next attempt.
• Use quick la and lh shortcuts for common ls options.
• Manage foreground/background jobs with Ctrl-Z, bg, and fg.
• Run independent tasks with native parallel -j N, fail-fast queueing, and JSONL task reports.
• Check generated scripts with wsh --check before executing them.

let workers = 4 * 2
if workers > 4 {
    print "Building with $workers workers"
    cargo build --jobs $workers
}

Performance snapshot

Measurements are from one development machine, not a standardized benchmark. The loop result covers this 20,000-iteration workload; results vary by machine and workload.

The repeatable benchmark suite compares the current worktree, the previous release, and Bash with interleaved samples. It covers startup, arithmetic, external commands, pipelines, event-driven waits, and bounded parallel tasks.

Agent and developer workflows

Build once with zig build -Doptimize=ReleaseFast, then invoke the native binary directly. Non-interactive commands skip prompt, history, and config loading:

./zig-out/bin/wsh --check script.wsh
./zig-out/bin/wsh --no-config -c "parallel -j 2 --fail-fast --report checks.jsonl 'zig build check' 'zig build -Doptimize=ReleaseFast'"

parallel runs Wolysh command strings in isolated child processes, inherits functions and variables, and refills a slot as soon as a task finishes. Reports record task indexes, exit statuses, and elapsed times separately from command output. See the agent workflow guide for the contract and examples.

Build from source

Linux x86_64 is the currently tested target. Building requires Zig 0.16.0:

zig build -Doptimize=ReleaseFast
./zig-out/bin/wsh

To install the source build, run sudo install -m 0755 zig-out/bin/wsh /usr/local/bin/wsh.

For a user-local installation without sudo:

zig build -Doptimize=ReleaseFast --prefix "$HOME/.local"
"$HOME/.local/bin/wsh" --version

Add $HOME/.local/bin to your existing shell's PATH if it is not already there.

Project status

Early stage and not a Bash or POSIX drop-in. Arithmetic expansion $((...)), brace expansion, <<-/<<< inputs, and the common builtins are in place; missing pieces include POSIX control flow (if cmd; then, case, until), process substitution <( ), the ${name:=} / ${name:?} / pattern-removal parameter operators, and extended globbing. See the language guide for features, configuration, key bindings, and the current limitations.

Recent changes are recorded in the changelog.

• Contributing
• Security policy
• Demo script

License

MIT. See LICENSE.