CLI Reference

The tjs binary is the entry point to txiki.js. It runs scripts, evaluates expressions, serves HTTP applications, runs tests, bundles and compiles code, and provides an interactive REPL.

tjs [options] [subcommand] [args]

Run tjs --help for a summary, or tjs <subcommand> --help-style usage by invoking a subcommand with missing arguments.

Global options

These options apply before the subcommand:

Option	Description
-v, --version	Print the version (v<version>) and exit
-h, --help	Print help and exit
--memory-limit LIMIT	Set the memory limit (in bytes) for the JavaScript runtime
--stack-size SIZE	Maximum JavaScript stack size, in bytes (default: 1024 KB)
--wasm-stack-size SIZE	WebAssembly stack size, in bytes (default: 512 KB)
--tls-ca FILE	Path to a custom CA bundle PEM file (overrides the embedded Mozilla bundle)

Subcommands

tjs run

Run a JavaScript program.

tjs run app.js

Option	Description
--import-map FILE	Path to an import map JSON file

If the file ends in .wasm, tjs run acts as a WASI runner instead of evaluating JavaScript.

tjs eval

Evaluate a JavaScript expression passed on the command line:

tjs eval "console.log(1 + 1)"

tjs serve

Serve an HTTP (or HTTPS) application from a module that default-exports a fetch handler:

tjs serve app.js

See the Serving HTTP guide for the module shape, WebSocket support, and TLS options.

tjs test

Run every test-*.js file in a directory (defaults to the current directory). Each test runs as a separate tjs run subprocess.

tjs test tests/

The test runner is tuned with environment variables:

Variable	Description
VERBOSE_TESTS	When set, print verbose output
TJS_TEST_TIMEOUT	Per-test timeout in milliseconds (default 30000)
TJS_TEST_CONCURRENCY	Number of tests to run in parallel (default: navigator.hardwareConcurrency)

tjs bundle

Bundle a JavaScript/TypeScript file (and its imports) into a single file using esbuild.

tjs bundle app.js bundle.js

See the Code Bundling guide for options and details.

tjs compile

Compile a single JavaScript file into a self-contained standalone executable.

tjs compile bundle.js

See the Standalone Executables guide.

tjs app

Manage TPK app packages — multi-file applications packaged into a .tpk archive or a standalone executable.

tjs app init      # scaffold a new app
tjs app pack      # package into a .tpk file
tjs app compile   # compile into a standalone executable

The REPL

Running tjs with no subcommand on a TTY starts an interactive read-eval-print loop with syntax-highlighted output and persistent command history.

tjs

Lines starting with . are directives rather than JavaScript:

Directive	Description
.help	Print the directive list
.time	Toggle display of evaluation timing
.strict	Toggle strict-mode evaluation
.depth N	Set the object inspection depth (default 2)
.hidden	Toggle display of non-enumerable properties
.color	Toggle colored output
.dark	Select the dark color theme
.light	Select the light color theme
.clear	Clear the terminal
.clear-history	Clear the command history
.load FILE	Load and evaluate source from a file
.quit	Exit the REPL

The toggle directives (.time, .strict, .hidden, .color) accept an optional boolean argument, e.g. .color yes. Command history is persisted to $TJS_HOME/history.db (see environment variables); on builds compiled without SQLite, history is silently disabled.

Reading a script from stdin

When tjs is run with no subcommand and stdin is not a TTY, it reads the entire input and evaluates it as a script. This makes tjs convenient in pipelines:

echo "console.log('hi')" | tjs
tjs < script.js

Running WASI modules

When the argument to tjs run ends in .wasm, txiki.js instantiates it as a WASI module against wasi_snapshot_preview1. The current directory (.) and the filesystem root (/) are pre-opened, any trailing arguments are forwarded to the module as WASI arguments, and the guest's exit code becomes the process exit code.

tjs run module.wasm arg1 arg2

For programmatic control over WASI, use the tjs:wasi module directly.

Environment variables

Variable	Description
TJS_HOME	Overrides the home/cache directory (default ~/.tjs). Stores the HTTP cookie jar (cookies.txt), the cached esbuild binary (esbuild/<version>/), and the REPL history database (history.db).
TJS_CA_BUNDLE	Path to a custom TLS CA bundle PEM file.
SSL_CERT_FILE	Fallback path to a custom TLS CA bundle PEM file.

The CA bundle is resolved with the precedence --tls-ca > TJS_CA_BUNDLE > SSL_CERT_FILE > the embedded Mozilla bundle.

Outbound HTTP requests also honor the standard proxy environment variables — see the HTTP Proxy Support guide.