Pytra

is Pytra's source language. Pytra transpiles that code into multiple target languages.

· Supported Backends ·

Features of Pytra

🐍 Python → Native code in each target language

• 🌐 Transpiles to C++, Rust, Go, Java, TS, and many more
• 🧩 Preserves the original program structure almost as-is
• ⚡ Generates high-performance code even when you write in Python
• ✨ Uses a simple Python subset
• 🛠 Works with existing tools such as VS Code
• 🔧 The core is also written in Python, so it is easy to extend
• 🔁 Supports self-hosting

Runtime Performance Comparison

These are execution times for sample programs written in Python and for their transpiled source code. Unit: seconds. In the table, Python is the original implementation and PyPy is included as a reference.

No.	Workload
06	Julia-set parameter sweep (GIF)	9.627	0.507	0.546	0.407	0.329	0.626
16	Chaotic rotation of a glass sculpture (GIF)	6.847	0.606	0.277	0.246	1.220	0.650

Full data for all languages and all samples: Sample page

Sample code: 06_julia_parameter_sweep.py Full source: sample/py/06_julia_parameter_sweep.py Transpiled code in each language C++ | Rust | C# | JS | TS | Dart | Go | Java | Swift | Kotlin | Ruby | Lua | Scala3 | PHP | Julia

Sample code: 16_glass_sculpture_chaos.py Full source: sample/py/16_glass_sculpture_chaos.py Transpiled code in each language C++ | Rust | C# | JS | TS | Dart | Go | Java | Swift | Kotlin | Ruby | Lua | Scala3 | PHP | Julia

Python vs Pytra

Aspect	Python	Pytra
Execution	Runs on the Python interpreter	Runs in each backend language
Integers	Arbitrary precision	int64, uint64, ..., int8, uint8
Floating point	64-bit	64-bit / 32-bit
Runtime speed	x1	x10 to x100 when transpiled to C++ or Rust
Backend optimization	Limited	Extensive
Multi-language deployment	❌	✅
Typing	Dynamic typing	Static typing
Bounds checks	Always enabled	Customizable
Platform integration	Python-centric	Fits each language's SDKs and tools
Distribution	Requires Python runtime	Uses each language's native distribution model
Multiple inheritance	✅	❌, single inheritance only
Mix-ins	✅	✅
Self-hosting	❌	✅

⚠ This project is still under active development and may be far from practical use. Review the sample code and use it at your own risk.

Read the Docs

• Japanese tutorial: docs/ja/tutorial/README.md
• Architecture: docs/ja/tutorial/architecture.md - an overview of the pipeline
• Japanese document index: docs/ja/index.md
• English tutorial: docs/en/tutorial/how-to-use.md
• English document index: docs/en/index.md

Changelog

2026-03-26 - Pipeline redesign completed. All six stages of the pipeline (parse -> resolve -> compile -> optimize -> link -> emit) now work end to end. The Go backend has been migrated to the new pipeline.

2026-03-25 - All P0 tasks completed. Reorganized the test/ directory. Go emitter and runtime reached parity on all 18 samples.

2026-03-24 - Started the pipeline redesign. Added toolchain2/, implemented pytra-cli2, and defined the EAST1/EAST2 specifications.

Full history: docs/en/changelog.md

License

Apache License 2.0