What are such games created on and what would you advise to use to create such games from a single source code?

Question

JavaScript

Hello.
A friend sent this gif-demo and asked to pick up a tool for creating games of this kind for all existing user devices (PCs, tablets, mobile phones, smart TVs, etc.) from a SINGLE source code .
What is this prototype game based on and what development tools can you recommend? (so that the code is not rewritten several times from platform to platform, etc.)
In advance, I thank everyone for the detailed answers and advice on implementing the plan!

Answer 1

The ideal option is
www.openfl.org (for html5 tagrete you can use https://github.com/YellowAfterlife/openfl-bitfive - an alternative backend that uses rendering on canvas is truncated in terms of capabilities, but it’s quite enough for such graphics)
+
haxeflixel.com
haxepunk.com
Uses under the hood opengl rendering on mobile platforms and PC.
In terms of performance, you should not expect records, but it's probably not better to port flash api to native. Unfortunately, I don't find any more benchmarks with source codes (openfl vs unity).
Assembly is elementary. No additional adaptation for individual platforms is required (well, except for html5)
If you have not tried haxe before, then immediately take it as an idewww.flashdevelop.org no plugins for sublime or ideas.
Unity3d IMHO will be heavy.