Doing the GMTK Game Jam with the Vectarine engine

Aug 13, 2026

Since a few years, I’ve been participating in the GMTK Game Jam, one of the largest game jams in the world.

To be honest, this jam was one of the reasons I built Vectarine. I felt like existing engines were not optimized for making games in time constraints situations and don’t allow you to easily turn your jam prototype into a full game.

I’m quite happy with how Vectarine performed during the jam, we built 5 hours to Y2K, a game about organizing the largest party possible in 5 hours.

As always, hot-reloading, exports to HTML and the general API were a joy to work with. As vectarine games are text based, we could collaborate using Git and GitHub with no issue to build features together.

However, there were a few improvement areas that we found during the jam and that were addressed in the new 0.6.0 release of Vectarine.

Most of them are related to the developer experience, something that is very important to the spirit of Vectarine, as outlined in the Design Principles of Vectarine.

loadScript

Before 0.6.0, you needed to call loadScript and wait for the script to we ready, which was annoying and hindered the creation of libraries as you needed for the library to be loaded before you could use it. Now, you can use require to load scripts, just like any other Lua runtime and it just works.

To do that, internally, Vectarine switched to an async execution model where we pause execution and resume it when the script is ready.

The ui module

The ui module was very good, but the way it dealt with text was strange: The size of the text was based on the size of the widget, and the text would be as big as it could to fit.

This is was not super convenient, so we switched to having a fontSize property to the text widgets. Also, we reworked the API to make it as convenient as possible. Now you can write this:

local ui = require("@vectarine/ui")

local textWidget = ui.text("My text")

local customizedTextWidget = ui.text("My text", {fontSize = 0.1, color = vec.V4(1, 0, 0, 1)})

local dynamicColorAndTextWidget = ui.text(function() return "My text" end, {fontSize = 0.1, color = function() return vec.V4(1, 0, 0, 1) end})

You can create the text widget with one simple line, or provide more options as needed, or even use functions to dynamically change the text and color. Previously, you were forced to define a function everytime which was a bit verbose.

And a lot more

We also made coord more convenient to use, made the aspect ratio of the game in the editor more logical (the editor toolbar is no longer rendered over the game!), and a lot of other improvements!

These resolved all (not most, ALL) of the issues we found during the jam, meaning that Vectarine is better than ever for making game during jams.

So, for your next game jam, pick Vectarine and have fun making your game!

Update to 0.6.0 and check out the release notes for more details.

There is no general-purpose game engine