Embedded scripting languages

The following is a list of reasonably mature or actively developed open source embedded scripting languages to use in your application. Stretching the definition of a scripting language, it also includes Datalog implementations. Items with a strong copyleft license (like the GNU GPL) that will apply to the rest of your code are emphasized as a warning.

To sort and filter the list interactively, visit the webpage. To contribute, go to the GitHub project.

Contents

List

Language Project name/link Implementated in GC License Notes
Ada HAC Ada None (stack only) MIT HAC implements a subset of the Ada language. Thus, it can share sources with the embedding application.
AngelScript AngelScript C++ Ref. counting + cycle-detecting tracing GC Zlib A statically typed curly brace language resembling C++ itself.
Anko Anko Go Go's GC MIT Scriptable interpreter with syntax similar to Go.
ArkScript ArkScript C++ None (resource release is destruction + optional manual MM) MPL-2.0 A small functional Lisp-like programming language. Separate bytecode compiler and VM.
Asp Asp C Ref. counting inside a static memory area MIT Python-like. Targets embedded systems. Allows blocking calls in scripts without blocking the application. Runs compiled bytecode. Not related to Microsoft’s Active Server Pages.
Awk Libmawk C Ref. counting GPL-2.0 Implements Awk. A fork of mawk 1.3 restructured for embedding.
Awk, Basic, Pascal Libfawk C Ref. counting BSD-3-Clause A multi-language VM. Includes compilers for three languages: Fawk (Awk dialect), Fbas (Basic dialect), and Fpas (Pascal dialect).
Basic MY-BASIC C Ref. counting + cycle-detecting tracing GC MIT A Basic dialect with prototype-based OOP.
Berry Berry C Tracing MIT Lightweight dynamically-typed embedded scripting language designed for lower-performance devices with limited memory.
Boron Boron C Tracing LGPL-3.0-or-later An embeddable scripting language similar to Rebol.
C PicoC C None (manual MM) BSD-3-Clause Statically typed. Interprets a subset of C.
C tcc C None LGPL-2.0-only A small C compiler that can be used as a library for a C JIT. libtcc header. Embedding example.
C#, other CLR languages Mono C Tracing MIT and other Implements the CLR.
ChaiScript ChaiScript C++ Ref. counting BSD-3-Clause A header-only C++14 interpreter library.
Clojure sci Clojure host VM's GC EPL-1.0 An interpreter for a subset of Clojure for Clojure and ClojureScript.
Common Expression Language (CEL) cel-go Go Go's GC Apache-2.0 A non-Turing-complete expression language.
Common Expression Language (CEL) cel-python Python Python's GC Apache-2.0 A non-Turing-complete expression language.
Common Expression Language (CEL) cel-rust Rust None MIT A non-Turing-complete expression language.
Common Lisp Clasp Common Lisp, C++ MPS GC (Boehm-Weiser also supported) LGPL-2.0-or-later Full Common Lisp implementation well integrated with C++, using LLVM for the code generation, to integrate closely with C++ applications or libraries.
Common Lisp Embeddable Common Lisp Common Lisp, C Boehm-Weiser GC LGPL-2.0-or-later Full Common Lisp implementation, available as a shared library libecl.so embeddable in any C, C++ or other application.
daScript daScript C++ None (region-based + manual MM?) BSD-3-Clause A statically-typed performance-oriented scripting language.
Datalog AbcDatalog Java JVM's GC BSD-3-Clause Implements Datalog.
Datalog Cascalog Clojure JVM's GC Apache-2.0 Implements Datalog.
Datalog Datalog (c-cube) OCaml OCaml's GC BSD-2-Clause Implements Datalog.
Datalog Datalog (fogfish) Erlang None (no collection inside interpreter state) Apache-2.0 Implements Datalog.
Datalog Datalog (MITRE Corporation) C Tracing (Lua's GC) LGPL-2.0-or-later Implements Datalog. It is implemented on top of Lua 5.3 and can be extended with Lua functions.
Dhall Dhall Haskell Haskell's GC BSD-3-Clause A statically-typed functional configuration language. Not Turing-complete. Untrusted code: can’t access the file system, can fetch Dhall libraries over HTTP(S) from static URLs (but libraries aren’t allowed to access your data), can use up memory and CPU time for a DoS attack. Has a work-in-progress Clojure and Ruby implementation.
DWScript DWScript Object Pascal (Delphi 2009 or later) Ref. counting + cycle-detecting tracing GC MPL-1.1, GPL-3.0 (JavaScript code generator) Description. A statically typed Delphi/Free Pascal-like language. Can compile to JavaScript.
Dyon Dyon Rust None (Rust-style lifetimes) Apache-2.0 or MIT Has optional, optimistic (succeed-by-default) static type checking.
Expr Expr Go Go's GC MIT Compiles and evaluates statically-typed expressions.
Falcon Falcon C++ Tracing GPL-2.0 or custom The GC is pluggable.
fe fe C Tracing MIT Uses a fixed-size memory region. No malloc.
Forth Atlast C None (manual MM) Public domain A dialect of Forth originally developed at Autodesk.
Forth FTH C Tracing BSD-2-Clause A dialect of Forth with objects, hashes, regular expressions, and other extensions.
Forth pForth C None (manual MM) Public domain A dialect of Forth.
GameMonkey Script GameMonkey Script C++ Tracing MIT Comes with C bindings. Similar to Lua, multithreaded.
Gentee Gentee Go Go's GC MIT Statically typed.
gluon gluon Rust Tracing MIT Statically typed. Inspired by Lua, Haskell, and OCaml. Each executing gluon thread gets a separate heap.
Go Yaegi Go Go's GC Apache-2.0 An embedded complete Go interpreter, on top of the Go runtime.
Gravity Gravity C Tracing MIT A class-based concurrent scripting language with a Swift-like syntax.
Groovy Groovy Java JVM's GC Apache-2.0 A scripting language for the JVM. A large subset of Java is valid Groovy. Integrating Groovy into applications.
Haxe HashLink C Tracing (lazy sweep) MIT A bytecode interpreter and a baseline JIT compiler (x86/x86_64 only) for Haxe.
Haxe, others Neko C Boehm MIT The NekoVM is a target for several compilers, including Haxe.
Interpreter Interpreter C++ None MIT A small interpreter in one header and one source code file with optional extensions (arithmetic operations, containers, filesystem, and others).
Io Io C Tracing BSD-3-Clause A prototype-based OO language.
Janet Janet C Tracing MIT A functional and imperative language with a Lisp syntax.
Java BeanShell Java JVM's GC Apache-2.0 An small, embeddable Java source code interpreter. Understands Java code with certain extensions like method closures.
JavaScript Duktape C Ref. counting + cycle-detecting tracing GC MIT Implements JavaScript E5/E5.1.
JavaScript Espruino C Tracing MPL-2.0 Implements a subset of JavaScript ES5 in a way suitable for embedded hardware with 8+ KiB RAM.
JavaScript Goja Go Go's GC MIT Implements ECMAScript 5.1. Better standard compliance and performance than otto.
JavaScript GraalJS C++, C, Java JVM's GC UPL-1.0 Implements ECMAScript 2022 for GraalVM (HotSpot JVM) using Truffle.
JavaScript JerryScript C Tracing Apache-2.0 A full ECMAScript 5.1 interpreter written in C99 and optimized for low memory consumption. Uses CMake.
JavaScript jsish C Ref. counting MIT A JavaScript ES 5.2+ interpreter. Internally structured after Tcl with an extensive C API. Features include subinterpreters, introspection, SQLite bindings, and a web framework with WebSocket support. The code is valid C and C++.
JavaScript MuJS C Tracing ISC Implements JavaScript (ES5). Has a similar C interface to Lua.
JavaScript njs C None (no collection performed) BSD-2-Clause Implements a subset of ES5.1 with some ES6 extensions.
JavaScript otto Go Go's GC MIT Implements ES5 with some limitations.
JavaScript QuickJS C Ref. counting + cycle-detecting tracing GC MIT A small embedded JavaScript interpreter that implements almost all of ES2019 and much of ES2020.
Jinx Jinx C++17 Ref. counting MIT Designed for use in realtime applications such as video games.
Jsonnet Jsonnet C++ Tracing Apache-2.0 A functional configuration language that extends JSON. Untrusted code: can’t access the file system or network, can use up memory and CPU time for a DoS attack. Has bindings for C, C++, Go, Python, and other languages, as well as a separate native Go implementation.
Ketos Ketos Rust None (no heap allocation)? Apache-2.0 A functional Lisp.
LIL LIL C, Object Pascal (separate implementations) None (no reference support) Zlib A Tcl-like language incompatible with mainline Tcl.
Lily Lily C Ref. counting + tracing GC MIT A language focusing on expressiveness and safety.
ljs ljs C Tracing MIT Lua 5.3, Lua 5.1, and LuaJIT with a C/C++/Java/JavaScript syntax. Can convert Lua source code to ljs.
Lua Go-Lua Go Go's GC MIT Implements a subset of Lua 5.2.
Lua GopherLua Go Go's GC MIT Implements Lua 5.1 with the added support for Go’s channels. Lacks the debug hooks and several functions from the C version.
Lua Lua C Tracing MIT The reference implementation of what is likely the world’s most popular embedded scripting language. Allows you to precompile scripts to bytecode. Versions 5.1-5.3, which are the ones used today, are not fully compatible with each other.
Lua LuaJ Java JVM's GC MIT A Lua 5.2 spec-compliant interpreter written in Java for JME and JSE. Complies Lua directly to JVM bytecode.
Lua LuaJIT C Tracing MIT Fully compatible with Lua 5.1. Has a built-in C FFI library. Performance comparison.
Lua Lua-ML OCaml OCaml's GC BSD-2-Clause Embeddable Lua 2.5 reimplementation that integrates with OCaml type and module system. It’s possible to extend or even replace the standard library with your own modules.
Lua Luau C Tracing MIT Roblox fork of Lua 5.1 as a scripting language for games to support a gradual type system as well as limiting the set of standard libraries exposed to the users and implements extra sandboxing features to be able to run unprivileged code. Whenever possible, Luau aims to be backwards-compatible with Lua 5.1 and at the same time to incorporate features from later revisions of Lua.
Lua luerl Erlang Tracing Apache-2.0 An implementation of Lua 5.2 in pure Erlang with some features like goto absent.
Lua MoonSharp C# CLR's GC BSD-3-Clause and other CLR Based Lua implementation that is 99% compatible with Lua 5.2
Lua Ravi C Tracing MIT “Ravi is a dialect of Lua with limited optional static typing and features a JIT compiler powered by MIR as well as support for AOT compilation to native code.”
Moirai Moirai Kotlin JVM's GC MIT A scripting language that calculates the worst-case execution time (WCET) before executing each script. Optimized for multi-tenant microservices and serverless applications.
Mond Mond C# CLR's GC MIT A dynamically typed scripting language with generators, async, remote debugging, and a binding API.
Never Never C Tracing MIT A statically typed functional programming language.
Nickel Nickel Rust Ref. counting MIT A configuration language with gradual typing and contracts. Python bindings.
Pascal Pascal Script Object Pascal None (manual MM) modified zlib/libpng-License with mandatory attribution Statically typed. Implements “most of Object Pascal”. Can’t define new classes.
Pawn Pawn C None (no heap allocation) Apache-2.0 with a clause to explicitly permit static linking A curly-brace language with a small-footprint VM. Represents data as 4/8-byte “cells”. Compiles to CPU-specific bytecode. More.
Perl Perl C Ref. counting Artistic-2.0 or GPL-3.0 Embedding Perl in Another Application
PHP ephp Erlang None (no collection inside interpreter state) LGPL-2.1-or-later Implements a subset of PHP 5.5.
PHP PH7 C Ref. counting Symisc Public License or proprietary Implements a subset of PHP 5.3 with some changes like native UTF-8 support.
Pluto Pluto C++ Tracing MIT A superset of Lua 5.4 (outside of incompatibilies caused by new syntax). Adds syntax like !=, break, and string interpolation; expands the standard library; somewhat improves performance.
pocketlang pocketlang C Tracing MIT A small language syntactically similar to Ruby. Embedding examples. Performance comparison.
Prolog Erlog Erlang None () Apache-2.0 Interprets a subset of standard Prolog.
Prolog Golog Go Go's GC MIT Implements a subset of standard Prolog.
Python CircuitPython C Tracing MIT A fork of MicroPython, designed for API uniformity across many microcontrollers.
Python gpython Go Go's GC BSD-3-Clause Implements a subset of Python 3.4.
Python GraalPy C, Java JVM's GC UPL-1.0 Implements Python 3 for GraalVM (HotSpot JVM) using Truffle.
Python Jython Java JVM's GC PSFL (BSD-like) An implementation of Python 2 for the JVM.
Python MicroPython C Tracing MIT Implements Python 3.4 syntax and some of the core datatypes.
Python PikaPython C Ref. counting MIT Implements a variant of Python 3. The degree of compatibility with Python seems to be undocumented. Runs in as little as 4 KiB of RAM. Targets microcontrollers and Linux.
Python pocketpy C++ Tracing MIT Implements a subset of Python 3 (with some differences) in a single C++17 header file.
Python Python C Ref. counting + cycle-detecting tracing GC PSFL (BSD-like) “Embedding Python in Another Application”.
QuakeC gmqcc/qcvm C++ None (no dynamic memory allocation) MIT A QuakeC compiler and VM.
Quirrel Quirrel C++ Ref. counting MIT A fork of Squirrel with new features.
Rebol Rebol C Tracing Apache-2.0 Relative Expression Based Object Language
Red Red Rebol, Red, Red/System Tracing BSD-3-Clause, BSL-1.0 A descendant of Rebol. Embeddable via libRed. Features a cross-platform native GUI system. Intended to have low memory usage.
Rexx NetRexx Java JVM's GC ICU (BSD-like)  
Rexx ooRexx C++ Tracing CPL Implements Rexx extended with objects.
Rhai Rhai Rust None (Rust-style lifetimes) MIT or Apache-2.0 An embedded scripting language for Rust inspired by ChaiScript.
Ring Ring C Tracing MIT An embeddable applications programming language with a large standard library and GIL-less multithreading.
Ruby JRuby Java JVM's GC Choice of EPL, GPL, and LGPL An implementation of Ruby on the JVM.
Ruby mruby C Tracing MIT A lightweight implementation of Ruby. Has a compile-time package manager.
Ruby mruby/c C Ref. counting BSD-3-Clause An even smaller implementation of Ruby for microcontrollers with limited memory.
Ruby Ruby C Tracing Choice of BSD-2-Clause, Ruby license, GPL-2.0 An embeddable object-oriented scripting language. Running Ruby in C.
Ruby TruffleRuby C, Java JVM's GC UPL-1.0 Implements Ruby for GraalVM (HotSpot JVM) using Truffle.
Rune Rune Rust Ref. counting MIT or Apache-2.0 An embeddable dynamic programming language. Asynchronous-first and const-evaluation.
Scheme Animula C Tracing Compiler: GPL-3.0-or-later, VM: LGPL-3.0-or-later An optimizing compiler and VM for embedded systems. R7RS.
Scheme Chibi Scheme C Tracing BSD-3-Clause Implements R7RS small.
Scheme CHICKEN Scheme C Tracing BSD-3-Clause Implements R5RS (with some changes). R7RS support is a work in progress. Examples of embedding CHICKEN.
Scheme GNU Guile C Boehm LGPL-3.0-or-later “Guile mostly implements R6RS.”
Scheme Kawa Java JVM's GC MIT R7RS. Supports the javax.script API. Evaluating Scheme expressions from Java.
Scheme s7 C Tracing BSD-3-Clause Implements a subset of R5RS/R7RS. Descended from TinyScheme.
Scheme Steel Rust Ref. counting + tracing GC Apache-2.0 or MIT Aims for eventual R5RS and R7RS compliance. Has extensions inspired by Racket.
Scheme TinyScheme C Tracing? BSD-3-Clause Implements a subset of R5RS.
SGScript SGScript C Ref. counting + tracing CG MIT Features include a built-in data serialization format, coroutines, class-based OOP, sandboxed evaluation, a built-in debugger and profiler.
Shine Shine C Tracing MIT A language based on Lua with additional safety and expressiveness features implemented as a fork of LuaJIT.
simpleeval simpleeval Python Python's GC MIT Evaluates expressions in a subset of Python.
Snek Snek C Tracing GPL-3.0-or-later A Python-inspired language. Targets “processors too small to run MicroPython”.
SquiLu SquiLu C++ Ref. counting MIT, some extensions LGPL or GPL A fork of Squirrel. Changes the syntax to accept a subset of JavaScript and C/C++. Implements Lua’s features like string pattern matching and global table manipulation functions. Adds extensions for database access (SQLite3, MySQL, PostgreSQL), sockets, and other features.
Squirrel Squirrel C++ Ref. counting MIT A language inspired by Lua and JavaScript/Python. Has a Lua-like C++ API. Differentiates itself from Lua with the use of reference counting in place of Lua’s tracing GC, a curly-brace syntax, built-in class-based OOP, and zero-indexed arrays.
Starlark Starlark (Go) Go Go's GC BSD-3-Clause A small dialect of Python for configuration. Not Turing-complete. Untrusted code: can’t access the file system and network, can use up memory and CPU to perform a DoS attack. Spec. Python bindings.
Starlark Starlark (Java) Java JVM's GC Apache-2.0 Starlark for the JVM. The original implementation.
Starlark Starlark (Rust) Rust ? Apache-2.0 Starlark in Rust. Python bindings.
Tcl Jim Tcl C Tracing BSD-2-Clause Largely compatible with Tcl 8.5 with its own additions.
Tcl JTcl Java Ref. counting Various BSD-like Tcl 8.4 with some 8.5 features for the JVM.
Tcl Molt Rust Ref. counting BSD-3-Clause A minimal Tcl implementation for Rust applications and libraries.
Tcl Picol C None (no reference support) BSD-2-Clause A header-only library interpreter for a limited dialect of Tcl.
Tcl Tcl C Ref. counting Tcl license (BSD-like) An embeddable general-purpose scripting language with a rich C API. Has a cross-platform GUI toolkit called Tk. How to embed Tcl in C applications.
Toy Toy C Ref. counting Zlib Has an optional type system. Embedding Toy.
Umka Umka C Ref. counting BSD-2-Clause Statically typed.
Wirefilter Wirefilter Rust None (no dynamic memory allocation) MIT An expression language for Wireshark-like filters.
Wren Wren C Tracing MIT A small class-based performance-oriented scripting language. Performance comparison.
ZetScript ZetScript C++ Ref. counting MIT Comes with an API for C++ interop.
zygomys zygomys Go Go's GC BSD-2-Clause An embedded Lisp for Go. Inspired by Clojure, but more oriented towards imperative programming. Has an infix syntax layer that looks like a subset of Go.

See also

Contributing

Your contributions are welcome! See CONTRIBUTING.

License

CC0

Disclosure

The curator of this document maintains Picol and has contributed to Jim Tcl.