CLI Reference

Every command

Piping works too — source on stdin is evaluated directly:

echo 'Log "Hi" to the <console>.' | aro

Running and checking

aro run ./MyApp                     # interpret
aro run ./MyApp -- --port 8080      # arguments after -- reach the application
aro check ./MyApp                   # errors, warnings, and per-route body analysis
aro check ./MyApp --no-warnings     # errors only
aro test ./MyApp --filter pricing   # run the tests whose name matches
aro test ./MyApp --compiled         # run the same tests through a native binary

Arguments the application reads

Application-Start declares the positionals it reads with the same takes clause user-defined actions use (ARO-0047), so a tool does not have to be invoked entirely in flags:

(Application-Start: Crawler takes <url> <depth>) {
    Extract the <site>  from the <parameter: url>.
    Extract the <args>  from the <parameter: arguments>.   # the whole list
    Return an <OK: status> for the <startup>.
}

./crawler https://example.com 3     # positional
./crawler --url https://example.com # a flag of the same name wins

Building a binary

aro build ./MyApp                   # native binary, static Swift runtime
aro build ./MyApp --release         # optimize + size + strip
aro build ./MyApp --emit-llvm       # LLVM IR text instead of a binary
aro build ./MyApp --dynamic         # ship libswift*.so beside the binary (rpath=$ORIGIN)
aro build ./MyApp --sign '-' --hardened-runtime

--static is the default and produces one self-contained file. On Linux, Foundation still links dynamically.

Comparing two revisions

aro diff compares the feature graph — nodes are feature sets, wires are events, Application.<Name> calls and repository observers — rather than lines of text. It is derived with the runtime's own matching rules, so what it shows is what the event bus will actually wire up:

aro diff --graph main..my-branch
aro diff --graph main..my-branch --html report.html

Plugins

aro new plugin my-csv --lang rust --actions --qualifiers
aro new plugin my-workflows --lang aro
aro add github:org/repo
aro plugins
aro remove my-csv

--lang is required: swift, rust, c, cpp, python or aro.

Interactive and notebook

aro repl                 # terminal REPL
aro repl --json          # line-delimited JSON on stdio, for front-ends
aro kernel install       # register the native Jupyter kernel (ZMQ, no Python)

Editor and assistant integration

aro lsp                  # Language Server over stdio
aro mcp                  # MCP server for LLM tooling
aro ask "add a rate limit to createOrder"
aro ui ./MyApp           # open Solaro at this project

aro lsp, aro mcp, aro ask and aro kernel are available on macOS and Linux; they are not built for Windows.

Discovering the language from the CLI

aro actions                    # all 71 built-in actions, with roles and prepositions
aro actions --qualifiers       # and every registered Compute qualifier
aro actions Retrieve           # one action in detail
aro actions --format json      # machine-readable, for tooling