Gluon is a statically-typed, functional programming language designed for embedding in Rust applications.
Gluon addresses the problem of safely extending host applications with scripting capabilities while maintaining type safety and performance. It achieves this through static typing combined with type inference, eliminating the need for explicit type annotations while preserving compile-time safety guarantees. The language uses a separate garbage-collected heap for each executing thread, reducing garbage collection overhead. Marshalling values between Rust and Gluon requires minimal boilerplate, allowing Rust functions to be directly exposed to Gluon code. The language supports Unicode natively with UTF-8 encoded strings and provides thread-safe execution, enabling multiple Gluon programs to run in parallel within a Rust application.
Gluon suits projects that need to embed a scripting layer in Rust while maintaining strong type safety guarantees. It is particularly valuable when you want to expose Rust functionality to scripts without extensive marshalling code or when you need multiple concurrent script execution contexts with isolated memory management. The tool works well for applications requiring both the performance and safety of Rust with the flexibility of a dynamically-evaluated embedded language. A REPL is available for interactive development and testing, and tooling support includes a language server providing code completion and formatting, along with a Visual Studio Code extension for syntax highlighting.
The project maintains active development with regular commits across the core compiler and supporting tools. Work continues on the language server and editor integrations, indicating ongoing investment in the developer experience. The parallel execution feature, while functional, is acknowledged as recent and potentially subject to refinement, suggesting the maintainers prioritize correctness over premature stability claims.
