1. JavaScript (and Node.js)
Let's get the obvious one out of the way. If you love Lua, you’ll feel right at home with modern JavaScript. Both are dynamically typed, excel at handling data with associative arrays (what Lua calls tables and JS calls objects), and treat functions as first-class
citizens. This means you can pass functions as arguments and return them from other functions, just like you're used to. While Lua is praised for its simplicity, JavaScript offers a massive ecosystem via Node.js and its package manager, npm. If you enjoy Lua’s flexibility for scripting but want access to an enormous library for web development, server-side applications, and tooling, JavaScript is the logical next step. The core concepts transfer so well that the transition is remarkably smooth.
2. Squirrel
Squirrel is perhaps the most direct spiritual successor to Lua on this list. Created specifically as a lightweight, embeddable scripting language for applications like video games, it was heavily inspired by Lua but opted for a C-like syntax that many developers find more familiar. Like Lua, it's small, fast, and easy to integrate with a C++ codebase. However, Squirrel introduces a few key differences that can be seen as quality-of-life improvements. It has distinct types for arrays and tables (whereas Lua uses tables for both), and it includes built-in support for classes. For game developers who love Lua's role in engines like those for 'Left 4 Dead 2' and 'Portal 2' (where Squirrel is also used), this language offers a similar feel with a slightly more structured, object-oriented approach out of the box.
3. Python
While Lua is defined by its minimalism, Python is famous for its "batteries-included" philosophy. So why would a Lua fan love it? Because both prioritize developer productivity and readability. Python's clean syntax and dynamic nature will feel familiar, but it comes with a vast standard library and an unparalleled ecosystem of third-party packages for everything from data science to web development. If you've ever wished Lua had a library for a specific task and found the options lacking, Python almost certainly has you covered. It's not as lightweight or typically as fast in raw execution as Lua or LuaJIT, but for general-purpose scripting, automation, and data analysis, Python's power and community support are undeniable.
4. Julia
If you use Lua for its speed and its strength in numerical or technical computing, then Julia is your high-performance upgrade. Julia was designed from the ground up for scientific computing, boasting performance that rivals C and Fortran while maintaining the interactive, dynamic feel of a scripting language. Like Lua, Julia is just-in-time (JIT) compiled, making it incredibly fast for number-crunching tasks. It even shares a quirky feature with Lua: 1-based indexing for arrays. For developers pushing the limits of Lua's performance for mathematical or data-heavy applications, Julia offers a compelling path forward without sacrificing the expressiveness and ease of use that make high-level languages so appealing.
5. Fennel
This is for the Lua developer who wants to stay in the Lua ecosystem but craves more powerful metaprogramming tools. Fennel is a Lisp dialect that compiles directly to clean, idiomatic Lua code. This means you can use it anywhere Lua runs—game engines, embedded systems, servers—and seamlessly interact with existing Lua libraries. Fennel gives you the power of Lisp macros, allowing you to write code that writes code and create expressive domain-specific languages, a concept Lua itself is known for enabling. Since the Fennel compiler has no runtime dependency, once your code is compiled to Lua, it's just Lua. It’s a perfect choice for those who love Lua’s core but wish it had a true macro system.
