Introduction

Structyl is a build orchestration CLI tool for multi-language projects. If you maintain implementations of the same library, algorithm, or API across multiple programming languages, Structyl helps you manage them as a unified project.

The Problem

Multi-language ("polyglot") projects face common challenges:

• Fragmented toolchains - Each language has its own build tools (cargo, pip, npm, go build...)
• Testing inconsistency - No standard way to verify implementations produce identical results
• Version chaos - Keeping version numbers synchronized across Cargo.toml, package.json, pyproject.toml
• Repetitive workflows - Running the same operations across all languages requires different commands

The Solution

Structyl provides:

• Unified commands - structyl build works for Rust, Python, Go, Node.js, .NET, and more
• Reference testing - JSON-based tests that run against all implementations
• Version propagation - Single VERSION file updates all language manifests
• Dependency ordering - Targets build in the correct order automatically
• Docker integration - Isolated builds with --docker flag

Use Cases

Structyl is designed for projects like:

• Algorithm libraries - Math, compression, encoding implementations
• Data format parsers - JSON, YAML, protocol buffer implementations
• SDK generators - Multi-language client libraries for APIs
• Educational projects - Same algorithm implemented in multiple languages
• Benchmarking suites - Performance comparisons across languages

Key Concepts

Targets

A target is a buildable unit in your project. There are two types:

• Language targets - Code implementations (Rust, Python, Go, etc.)
• Auxiliary targets - Supporting tasks (documentation, websites, utilities)

Toolchains

A toolchain maps standard commands (build, test, clean) to language-specific tools:

Toolchain	Build Command	Test Command
cargo	cargo build	cargo test
go	go build ./...	go test ./...
npm	npm run build	npm test
uv	uv build	uv run pytest

Commands

Structyl provides 14 standard commands. Availability per toolchain varies:

• clean - Remove build artifacts
• restore - Install dependencies
• build - Compile/package
• build:release - Build with release optimizations (toolchain support varies)
• test - Run tests
• test:coverage - Run tests with coverage (requires custom definition; see commands spec)
• check - Run static analysis (lint, typecheck, format-check)
• check:fix - Auto-fix static analysis issues
• bench - Run benchmarks
• demo - Run demo/example
• doc - Generate documentation
• pack - Create distributable package
• publish - Publish package to registry
• publish:dry - Dry-run publish (validate without uploading)

Next Steps

• Installation - Install Structyl
• Quick Start - Create your first project
• Contributing - Development guide