Relux

Expect-style integration testing for interactive shell programs.

test "service healthcheck" {
    let DATABASE_PORT := available_port()
    let SERVICE_PORT := available_port()
    
    start Service as service { DATABASE_PORT, SERVICE_PORT }
    
    shell test {
        > curl localhost:${SERVICE_PORT}/status
        <? ^status: running
    }
}

Relux sends input to PTY shells and matches output against regex or literal patterns with timeouts. Tests read like a transcript of a shell session - send a command, match the response, repeat.

Features

• Pattern matching - literal (<=) and regex (<?) with capture groups
• Timeouts - per-operator, per-test, and suite-level, with tolerance and assertion modes
• Effects - declarative test infrastructure with dependency graphs and automatic teardown
• Parallel execution - run tests concurrently with isolated environments
• Functions and modules - extract reusable logic, organize suites across files
• Fail patterns - continuous background monitoring for errors
• HTML reports - rich test output with shell I/O logs
• Single binary - no runtime dependencies

Installation

cargo install relux

Or build from source:

git clone https://github.com/shizzard/relux.git
cd relux
cargo build --release

Pre-built binaries are also available on the Releases page.

Quick start

relux new                        # scaffold a project
$EDITOR relux/tests/hello.relux  # write a test
relux run                        # run all tests

Documentation

• DSL Tutorial - learn the Relux language from scratch
• Suite Tutorial - build a real-world test suite with shared infrastructure
• Reference - semantic model, configuration, syntax, built-in functions, CI integration

Editor support

• VS Code / Cursor: Visual Studio Marketplace
• VSCodium / code-server: Open VSX
• IntelliJ family: JetBrains Marketplace

See the editor support reference for details.

Claude Code plugin

Relux ships a Claude Code plugin - composable skills for authoring, running, and diagnosing Relux suites, surfaced as /relux:<skill-name> slash commands and auto-triggered while you work.

claude plugin marketplace add shizzard/relux
claude plugin install relux@relux

See agents/README.md for the skill catalog and how it is structured.